Allied Telesis Switch AT GS950 10PS User Manual

AT-GS950/10PS  
Gigabit Ethernet PoE+ Switch  
AT-GS950/10PS Switch Web Interface User’s Guide  
AT-S110 [1.00.013]  
613-001770 Rev A  
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Contents  
List of Figures .................................................................................................................................................. 9  
List of Tables ................................................................................................................................................. 13  
Preface ............................................................................................................................................................ 15  
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Contents  
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AT-GS950/10PS Switch Web Interface User’s Guide  
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Contents  
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AT-GS950/10PS Switch Web Interface User’s Guide  
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Contents  
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List of Figures  
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Figures  
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AT-GS950/10PS Switch Web Interface User’s Guide  
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Figures  
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List of Tables  
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List of Tables  
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Preface  
This guide contains instructions on how to use the AT-S110 Management  
Software to manage and monitor the AT-GS950/10PS Gigabit Ethernet  
PoE+ Switch.  
The AT-S110 Management software has a web browser interface that you  
can access from any management workstation on your network that has a  
web browser application.  
This preface contains the following sections:  
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Preface  
Document Conventions  
This document uses the following conventions:  
Note  
Notes provide additional information.  
Caution  
Cautions inform you that performing or omitting a specific action  
may result in equipment damage or loss of data.  
Warning  
Warnings inform you that performing or omitting a specific action  
may result in bodily injury.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
Allied Telesis Contact Information  
If you need assistance with this product, you may contact Allied Telesis  
technical support by going to the Support & Services section of the Allied  
Telesis web site at www.alliedtelesis.com/support. You can find links for  
the following services on this page:  
24/7 Online Support - Enter our interactive support  
center to search for answers to your questions in our  
knowledge database, check support tickets, learn  
about RMAs, and contact Allied Telesis technical  
experts.  
USA and EMEA phone support - Select the phone  
number that best fits your location and customer type.  
Hardware warranty information - Learn about Allied  
Telesis warranties and register your product online.  
Replacement Services - Submit a Return Merchandise  
Authorization (RMA) request via our interactive support  
center.  
Documentation - View the most recent installation  
guides, user guides, software release notes, white  
papers and data sheets for your product.  
Software Updates - Download the latest software  
releases for your product.  
For sales or corporate contact information, go to  
www.alliedtelesis.com/purchase and select your region.  
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Preface  
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Section I  
Getting Started  
This section contains the following chapters:  
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Chapter 1  
Starting a Web Browser Session  
This chapter contains the procedures for starting, using, and quitting a web  
browser management session on the AT-GS950/10PS switch. This  
chapter includes the following sections:  
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Chapter 1: Starting a Web Browser Session  
Establishing a Remote Connection to the Web Browser Interface  
The AT-GS950/10PS switch is shipped with a pre-assigned IP address of  
192.168.1.1. After your initial login, Allied Telesis suggests that you assign  
a new IP address to your switch. To manually assign an IP address to the  
Address” on page 30. To configure the switch to obtain its IP configuration  
from a DHCP server, refer to “DHCP Client Configuration” on page 45.  
Whether you use the pre-assigned IP address or assign a new one, you  
must set your local PC to the same subnet as the switch.  
To start a web browser management session, perform the following  
procedure:  
1. Start your web browser.  
2. In the URL field of the browser, enter 192.168.1.1.  
This is the default IP address of the switch. See Figure 1.  
Switch’s IP Address  
Figure 1. Entering a Switch’s IP Address in the URL Field  
The AT-S110 Management Software displays the login dialog box. See  
Figure 2. Management Login Dialog Box  
3. Enter the AT-S110 management login user name and password.  
The default user name is “manager” and the default password is  
“friend.” The login name and password are case-sensitive.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
4. Press OK.  
The AT-GS950/10PS Switch Information page is displayed. See Figure  
Note  
To change the user name and password, refer to “User Name and  
Figure 3. AT-GS950/10PS Switch Information Page  
The main menu appears on the left side and is common for all of the  
management pages discussed in this manual. It consists of the following  
folders and web pages:  
Switch Info  
Front Panel  
System  
Physical Interface  
Bridge  
SNMP  
Access Control  
RMON  
Voice VLAN  
Security  
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Chapter 1: Starting a Web Browser Session  
LLDP  
Statistics Chart  
Tools  
Save Configuration  
5. To see the front panel of the switch, select Front Panel from the main  
menu on the left side of the page.  
The AT-S110 Management software displays the front of the switch.  
Ports are green that have a link to an end node. Ports without a link  
are grey. The AT-GS950/10PS switch front panel page is shown in  
Figure 4. Front Panel Page  
A web browser management session remains active even if you link to  
other sites. You can return to the management web pages anytime as long  
as you do not quit your browser session or the management session does  
not time out. The default time-out is 10 minutes.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
Web Browser Tools  
You can use the web browser tools to move around the management  
pages. Selecting Back on your browser’s toolbar returns you to the  
previous display. You can also use the browser’s Bookmark feature to  
save the link to the switch.  
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Chapter 1: Starting a Web Browser Session  
Quitting a Web Browser Management Session  
To exit a web browser management session, close the web browser.  
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Chapter 2  
System Configuration  
This chapter provides procedures to configuring basic system parameters  
for the AT-GS950/10PS switch and contains information for the following  
sections:  
Note  
To permanently save your new settings or any changes to the  
configuration file, select Save Configuration to Flash from the main  
menu on the left side of the page.  
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Chapter 2: System Configuration  
System Management Information  
This section explains how to assign a name, location, and contact  
information for the AT-GS950/10PS switch. This information helps in  
identifying each specific AT-GS950/10PS switch among other switches in  
the same local area network. Entering this information is optional.  
Note  
Allied Telesis recommends that you assign a name to the switch.  
Naming each switch can help you identify the specific switch you  
want to manage among others. It can also help to avoid performing  
a configuration procedure on the wrong switch.  
To set a switch’s administration information, perform the following  
procedure:  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select Management.  
The Management Page is displayed. See Figure 5 for the  
AT-GS950/10PS Management Page.  
Figure 5. AT-GS950/10PS Management Page  
3. Configure the following parameters as necessary:  
System Description - Specifies the Allied Telesis switch model.  
You cannot change this parameter.  
System Object ID - Indicates the unique SNMP MIB object  
identifier that identifies the switch model. You cannot change this  
parameter.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
System Name - Specifies a name for the switch, for example,  
Sales. The name is optional and may contain up to 15 characters.  
System Location - Specifies the location of the switch. The  
location is optional and may contain up to 30 characters.  
System Contact - Specifies the name of the network administrator  
responsible for managing the switch. This contact name is optional  
and may contain up to 30 characters.  
4. Click Apply.  
5. From the main menu on the left side of the page, click on Switch Info.  
The Switch Information page is displayed. See “AT-GS950/8 Switch  
Information Page” on page 21 for more information.  
6. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 2: System Configuration  
Configuration of IP Address, Subnet Mask and Gateway Address  
This procedure explains how to change the IP address, subnet mask, and  
gateway address of the switch. Before performing the procedure, note the  
following:  
A gateway address is only required if you want to  
remotely manage the device from a management  
station that is separated from the switch by a router.  
To configure the switch to automatically obtain its IP  
configuration from a DHCP server on your network, go  
To change the switch’s IP configuration, perform the following procedure:  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select IP Setup.  
The IP Setup Page is displayed. See Figure 6.  
Figure 6. IP Setup Page  
3. Change the IP configuration parameters by observing or entering new  
information in the following fields:  
System MAC Address - This parameter displays the MAC  
address of the switch. You cannot change this parameter.  
System IP Address - Displays the current IP address of the  
switch. To change the IP address, enter a new IP address.  
When DHCP is enabled, you cannot change this parameter.  
System Subnet Mask - Displays the current subnet mask of the  
switch. To change the subnet mask, enter a new subnet mask.  
When DHCP is enabled, you cannot change this parameter.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
System Default Gateway - Displays the default gateway of the  
switch. To change the default gateway, enter a new gateway.  
When DHCP is enabled, you cannot change this parameter.  
DHCP Mode - For information about setting this parameter, refer to  
4. Click Apply.  
Note  
Changing the IP address ends your management session. To  
resume managing the device, enter the new IP address of the switch  
in the web browser’s URL field, as shown in Figure 1 on page 20.  
5. After you log on to the switch with the new IP address, select Save  
Configuration to Flash from the main menu on the left side of the  
page to save the new IP address to memory.  
Caution  
If you do not select Save Configuration to Flash, the IP address  
will revert to its original setting when you power cycle or reboot the  
switch.  
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Chapter 2: System Configuration  
IP Access List Configuration  
When the IP Access List feature is enabled, remote access to the  
AT-S110 management software is restricted to the IP addresses entered  
into the IP Access List.  
The procedures in this section describe how to enable or disable the IP  
Access List feature and how to add or remove IP addresses from the list.  
See the following sections:  
Note  
To modify IP address that has already been created, it must first be  
deleted and them re-created using the following procedures.  
Create an IP To create a list of accessible IP addresses, perform the following  
procedure:  
Access List  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select IP Access List. The IP Access List  
Page is displayed. See Figure 7.  
.
Figure 7. IP Access List Page  
3. Enter an IP address in the IP Address field using a xxx.xxx.xxx.xxx  
format.  
4. Click Add.  
The IP address is added to the IP Access List table in the Accessible  
IP column.  
Note  
You can add up to 10 IP address to the IP Access List table.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
5. From the IP Restriction Status field, select one of the following  
choices from the pull-down menu:  
Enable - This selection restricts the access to the AT-S110  
management software to the IP addresses in the table listed under  
Accessible IP.  
Disable - This selection allows unrestricted access to the AT-S110  
management software.  
6. Click Apply.  
Access to the management software is now restricted to those IP  
addresses listed in the IP Access List table.  
7. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
Delete an IP To delete an IP address from the IP Access List, perform the following  
procedure:  
Address List  
Entry  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select IP Access List.  
The IP Access List Page is displayed. See Figure 7 on page 32.  
3. Select Delete next to the IP address that you want to remove.  
The IP address is removed from the IP Access List table. If you  
remove the last IP address from the table, the IP Restriction Status  
field is set to Disable.  
4. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 2: System Configuration  
User Name and Password Configuration  
Password protection is always enabled for access to the AT-S110  
Management software. This section explains how to create new users  
names and passwords and how to modify or delete existing users for the  
web interface. See the following sections:  
Add New User The default User Name and Password is “manager” and “friend” - both  
without the quotes. To configure new User Name and Password  
information, perform the following procedure:  
Name and  
Password  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select Administration.  
The Administration Page is displayed. See Figure 8.  
Figure 8. Administration Page  
3. To create a user name, enter a user name in the box next to the User  
Name field.  
You can enter a value of up to 12 alphanumeric characters. The User  
Name field is case sensitive.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
4. To add a password that corresponds to the user name entered in  
step 3, enter a password of up to 12 alphanumeric characters in the  
box next to the Password field. The Password field is case sensitive.  
5. To confirm the password entry, retype the password in the box next to  
the Confirm Password field.  
6. Click Add to activate your changes on the switch.  
7. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
Modify User To modify the a user name password, perform the following procedure:  
Name and  
Password  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select Administration.  
The Administration Page is shown in Figure 8 on page 34.  
3. Identify the user name that you want to change and click Modify in the  
Action column.  
The Modify Administration Page is displayed. See Figure 9.  
Note  
The default user name cannot be modified or deleted. The default  
password can be modified.  
Figure 9. Modify Administration Page  
4. To change a password, enter a password of up to 12 alphanumeric  
characters in the box next to the Password field.  
5. To confirm the above password, retype the password in the box next to  
the Confirm Password field.  
6. Click Apply to activate your changes on the switch.  
7. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 2: System Configuration  
Delete User Name To delete a user name that you have previously added, perform the  
following procedure.  
and Password  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select Administration.  
The Administration Page is shown in Figure 8 on page 34.  
3. Identify the user name that you want to delete and click Delete.  
The user name is removed from the Administration table.  
Note  
The default user name cannot be modified or deleted. The default  
password can be modified.  
4. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
User Interface Configuration  
This procedure explains how to enable and disable the user interfaces on  
the switch. With this procedure you can enable or disable the AT-GS950/  
10PS SNMP Agent. For more information about SNMP, go to Chapter 20,  
“Simple Network Management Protocol SNMPv1 and v2c” on page 263  
and Chapter 21, “Simple Network Management Protocol SNMPv3” on  
page 273.  
Note  
The Web Server Status is displayed as Enabled for your  
information only. The Web Server cannot be disabled.  
SNMP Interface To enable or disable the AT-GS950/10PS SNMP interface, perform the  
following procedure:  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select User Interface.  
The User Interface Page is displayed. See Figure 10.  
Figure 10. User Interface Page  
3. Choose Enable or Disable from the pull down list for the SNMP Agent  
parameter.  
Enabled - When you enable this parameter, the SNMP agent is  
active. You can manage the AT-GS950/10PS switch with Network  
Management Software and the switch’s private MIB.  
Disabled - When you enable this parameter, the SNMP agent is  
inactive.  
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Chapter 2: System Configuration  
Note  
See Chapter 20, “Simple Network Management Protocol SNMPv1  
and v2c” on page 263 and Chapter 21, “Simple Network  
Management Protocol SNMPv3” on page 273 to configure the  
remaining SNMP parameters.  
4. Click Apply located under the Web Server Status Enable/Disable  
field.  
5. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
User Interface To set the Web Idle Timeout, perform the following procedure:  
Timeout  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select User Interface.  
The User Interface Page is displayed. See Figure 10 on page 37.  
3. Refer to the bottom portion of the web page. Enter the Web Idle  
Timeout parameter. The range is from 3 to 60 minutes.  
4. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
System Time  
The procedures in this section describe how to configure the system time  
by manually entering the time or through SNTP and how to configure the  
daylight savings time feature. See the following sections:  
Manually Setting To set the system time manually, perform the following procedure:  
System Time  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select System Time.  
The System Time Page is displayed. See Figure 11.  
Figure 11. System Time Page  
3. Use the pull down menu to set the Clock Mode parameter to  
Local time.  
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Chapter 2: System Configuration  
4. In the Local Time Settings section, set the Date Setting  
(YYYY:MM:DD) to the current date in the YYYY:MM:DD format.  
5. In the Local Time Settings section, set the Time Settings  
(HH:MM:SS) to the current time in the HH:MM:SS format.  
6. Click the Apply button at the bottom of the page.  
The time will take effect immediately.  
7. Save your new settings or any changes to the configuration file by  
selecting Save Configuration to Flash from the main menu on the left  
side of the page.  
Setting SNTP To configure SNTP, perform the following procedure:  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select System Time.  
The System Time Page is displayed. See Figure 11 on page 39.  
3. Use the pull down menu to set the Clock Mode parameter to SNTP.  
4. Enter the IP address of the SNTP Primary Server. The format is  
xxx.xxx.xxx.xxx.  
5. Enter the IP address of the SNTP Secondary Server. The format is  
xxx.xxx.xxx.xxx.  
6. Enter the SNTP Poll Interval. The range is 1 - 60 minutes.  
7. Enter the local Time Zone from the pull down menu.  
8. Click the Apply button at the bottom of the page.  
The switch will immediately start polling the SNTP primary server for  
time information.  
9. Save your new settings or any changes to the configuration file by  
selecting Save Configuration to Flash from the main menu on the left  
side of the page.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
Setting Daylight If you want to configure the switch for daylight savings time, perform the  
following procedure:  
Savings  
Parameters  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select System Time.  
The System Time Page is displayed. See Figure 11 on page 39.  
3. In the Daylight Savings Time Status field, select Enabled.  
4. Specify the Month, Day, Hour and Minute when Daylight Savings will  
take effect in the From time fields.  
5. Specify the Month, Day, Hour and Minute when Daylight Savings will  
end in the To time fields.  
6. Using the pull down menu, specify the Daylight Savings offset in the  
DST Offset field. You can select either 1 hr or 1/2 hr.  
7. Save your new settings or any changes to the configuration file by  
selecting Save Configuration to Flash from the main menu on the left  
side of the page.  
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Chapter 2: System Configuration  
SSL Settings  
The AT-GS950/10PS switch has a web browser server for remote  
management of the unit with a web browser application from management  
workstations on your network. By default, the server operates in a  
non-secure HTTP mode and can be configured to communicate in a  
secure HTTPS mode with SSL protocol.  
In many situations, the communication with the switch will be in a  
controlled environment and it is acceptable to communicate with the  
management software in the HTTP mode.  
However, you may find that your management communications are  
subject to outside security risks and web sessions conducted in the non-  
secure HTTP mode are vulnerable to security issues because the packets  
are sent in clear text. Web browser management sessions that use the  
secure HTTPS mode with SSL protocol are protected against snooping  
because the packets exchanged between the switch and your  
management workstations are encrypted. When operating in this mode,  
only the AT-GS950/10PS switch and the web browser are able to decipher  
the packets sent and received between them.  
Configuring SSL To enable or disable the SSL protocol feature, perform the following  
procedure:  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select SSL Settings.  
The SSL Settings Page is displayed. See Figure 12.  
Figure 12. SSL Settings Page  
3. From the SSL Settings field, select one of the following choices from  
the pull-down menu:  
Enable - The secure SSL mode is active. You must log in to the  
switch’s management using the HTTPS mode on your browser.  
Disable - The secure SSL mode is inactive. You must log in to the  
switch’s management using the HTTP mode on your browser.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
4. Click Apply.  
The SSL setting that you have selected is now active.  
5. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 2: System Configuration  
DHCP and ATI Web Discovery Tool  
The AT-GS950/10PS Gigabit Ethernet Smart switch is managed through a  
web browser interface only. The factory default IP address is 192.168.1.1.  
The switch does not have a local console connector, which means that  
you cannot learn what the switch’s management IP address is on a web  
browser without first knowing what the address is. Once the IP address is  
known, you can enter it in the browser.  
When the DHCP feature is enabled, a DHCP server automatically assigns  
an IP address which is not advertised over the network. As a  
consequence, you do not know what IP address has been assigned to the  
switch.  
Note  
The new IP address assignment from the DHCP server may take  
one to two minutes before the process is completed.  
Fortunately, there is an ATI Web Discovery Tool available that resolves  
this issue. It detects the MAC address, IP address and other information of  
the AT-GS950 series switches that are present on your local area  
network.  
Note  
The ATI Web Discovery Tool is available for download on the AT-  
GS950/10PS product page at alliedtelesis.com.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
DHCP Client Configuration  
This procedure explains how to activate and deactivate the DHCP client  
on the AT-GS950/10PS switch. When the client is activated, the switch  
obtains its IP configuration including an IP address and subnet mask from  
a DHCP server on your network. Before performing the procedure, note  
the following:  
By default, the DHCP client is disabled on the switch.  
The DHCP client supports DHCP Auto Configuration  
on page 47 for more information.  
After you enable DHCP, your current management  
session ends because a different IP address is  
assigned to the switch by the DHCP server. The new  
IP address can be discovered using the ATI Discovery  
page 44 for more information.  
To activate or deactivate the DHCP client on the switch, perform the  
following procedure:  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select IP Setup.  
The IP Setup Page is shown in Figure 6 on page 30.  
3. From the pull-down menu next to the DHCP Mode field, select Enable  
or Disable.  
4. Click Apply.  
When the DHCP client is Enabled, the web server connection to the  
switch is lost because a different IP address is assigned to the switch  
by the DHCP server.  
Caution  
Enabling DHCP may end your current management session.  
5. Use the ATI Web Discovery Tool to find the new IP address assigned  
to the switch by the DHCP server. See “DHCP and ATI Web Discovery  
Tool” on page 44 for more information.  
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Chapter 2: System Configuration  
Note  
The ATI Web Discovery Tool is available for download on the AT-  
GS950/10PS product page at alliedtelesis.com.  
6. Follow the procedure to log on with the new IP address provided by  
the DHCP Server as described in “Establishing a Remote Connection  
to the Web Browser Interface” on page 20.  
7. Save your new settings or any changes to the configuration file by  
selecting Save Configuration to Flash from the main menu on the left  
side of the page.  
If you do not save the new configuration when DHCP is enabled, the  
software reverts to the previously saved IP address value when the  
switch is power cycled or rebooted. If no IP address has been  
previously saved, the IP address value reverts to 192.168.1.1.  
If you enable DHCP and then save your configuration, you are saving  
the DHCP setting (Enabled). The next time the switch boots up, it will  
use the DHCP process to establish the IP address used to manage the  
AT-GS950/10PS switch.  
If you enter a new IP address after disabling DHCP and save your  
configuration, the DHCP setting (Disabled) and the new IP address on  
the switch is saved. The next time the switch boots up, it will respond  
to the IP address that you entered when you re-establish contact with  
the AT-S110 Management software.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
DHCP Auto Configuration  
If you need to automatically update the switch’s configuration files via a  
remote server, the DHCP Auto Configuration feature is available for this  
purpose via the DHCP server.  
Note  
You must enable the DHCP client so that this feature can operate  
for more information.  
To configure this feature on the switch, perform the following procedure:  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select System.  
The DHCP Auto Configuration Settings Page is shown in Figure 13.  
Figure 13. DHCP Auto Configuration Settings Page  
3. From the Auto Configuration State field, select one of the following  
choices from the pull-down menu:  
Enable - The DHCP Auto Configuration feature is active.  
Note  
You must enable the DHCP client so that this feature can operate  
for more information.  
Disable - The DHCP Auto Configuration feature is inactive.  
4. Click Apply.  
The DHCP Auto Configuration setting that you have selected is now  
active.  
5. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 2: System Configuration  
System Information Display  
The Switch Information page is initially displayed when you first log into  
the AT-GS950/10PS switch. It provides general information about the  
switch. To view this information, perform the following procedure:  
1. From the main menu on the left side of the page, select Switch Info.  
The Switch Information Page is displayed. See Figure 14.  
Figure 14. AT-GS950/10PS Switch Information Page  
The Switch Information Page displays the following information:  
System Up For - The number of days, hours, and minutes that the  
switch has been running since it was last rebooted.  
Runtime Image - The version number of the runtime firmware.  
Boot Loader - The version number of the bootloader firmware.  
Hardware Information Section:  
Version - The hardware version number.  
DRAM Size - The size of the DRAM, in megabytes.  
Flash Size - The size of the flash memory, in megabytes.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
Administration Information Section:  
Switch Name - This parameter displays the name assigned to the  
switch. To assign the switch a name, refer to “System  
Switch Location - This parameter displays the location of the  
switch. To assign the location, refer to “System Management  
Switch Contact - This parameter displays the contact person  
responsible for managing the switch. To assign the name of a  
System MAC Address, IP Address, Subnet Mask, and Gateway  
Section:  
MAC Address - This parameter displays the MAC address of the  
switch.  
IP Address - This parameter displays the system IP address.  
Address” on page 30 to manually assign an IP address or “DHCP  
Client Configuration” on page 45 to activate the DHCP client.  
Subnet Mask - This parameter displays the subnet mask for the  
Gateway Address” on page 30 to manually assign a subnet mask  
client.  
Default Gateway - This parameter displays the default gateway IP  
Gateway Address” on page 30 to manually assign a gateway  
DHCP client.  
Automatic Network Features Section:  
DHCP Mode - This parameter displays the status of the DHCP  
client on the switch. For information about setting this parameter,  
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Chapter 2: System Configuration  
System Log Configuration  
The System log is designed to monitor the operation the AT-GS950/10PS  
switch by recording the event messages it generates during normal  
operation. These events may provide vital information about system  
activity that can help in the identification and solutions of system  
problems.  
To configure the System log, perform the following procedure:  
1. From the main menu on the left side of the page, click the System  
folder.  
The System folder expands.  
2. From the System folder, select System Log Configuration.  
The System Log Configuration Page is displayed. See Figure 15.  
Figure 15. System Log Configuration Page  
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AT-GS950/10PS Switch Web Interface User’s Guide  
3. From the Syslog Status field, select one of the following choices from  
the pull-down menu:  
Enable - The System log is active.  
Disable - The System log is inactive.  
4. From the Time Stamp field, select one of the following choices from the  
pull-down menu:  
Enable - Each event message recorded in the log will have a time  
stamp recorded with it.  
Disable - No time stamp will be recorded with the event messages.  
5. Enter the Messages Buffer Size.The range is between 1 and 200.  
6. Enter the Syslog Server IP Address. The format is xxx.xxx.xxx.xxx. If  
the address is left at the default setting of 0.0.0.0, no server is  
specified.  
7. In the Facility field, enter the Facility local from the pull-down menu.  
The choices range from local0 through local7.  
8. Select the Logging Level. This parameter specifies what level of  
event messages will be logged into the System log. Your choices are  
as follows:  
0 Emergency - The system is unusable.  
1 Alert - Action must be taken immediately.  
2 Critical - Critical conditions are displayed.  
3 Error - Error conditions are displayed.  
4 Warning - Warning conditions are displayed.  
5 Notice - Normal but significant conditions are displayed.  
6 Informational - Informational messages are displayed  
7 Debug - Debug-level messages are displayed.  
9. Click Apply.  
The System log is now active.  
10. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 2: System Configuration  
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Chapter 3  
Port Configuration  
This chapter provides a description of the physical characteristics of the  
ports and a procedure that explains how to view and change the port  
settings. This chapter includes the following sections:  
Note  
To permanently save your new settings or any changes to the  
configuration file, select Save Configuration to Flash from the main  
menu on the left side of the page.  
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Chapter 3: Port Configuration  
Overview  
This chapter describes how to display and modify the physical  
characteristics of an AT-GS950/10PS switch. You can display and modify  
the settings of all the ports on one web page. The port characteristics that  
are displayed are:  
Trunk Group Number  
Port type  
Link Status  
Admin Status  
Duplex Mode  
Jumbo frame  
Flow control  
EAP Pass  
BPDU frame  
These characteristics are described in the next section.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
Displaying and Configuring Ports  
This procedure explains how to configure the ports on the  
AT-GS950/10PS switch using the Port Configuration Page. This page  
allows you to view and configure the parameter settings of individual or all  
the switch ports at one time.  
To configure the ports, perform the following procedure:  
1. From the main menu on the left side of the page, select Physical  
Interface.  
Figure 16. AT-GS950/10PS Physical Interface Page  
2. Adjust the port settings as needed. Not all parameters are adjustable.  
The parameters are defined as follows:  
Port - Specifies the port number. The All value indicates ports 1  
through 10 on the AT-GS950/10PS switch. You cannot change this  
parameter.  
Note  
You can use the All row value in the Port column to set the Admin.  
Status, Mode, Jumbo, Flow Ctrl, EAP Pass, and BPDU fields to  
the same values for all ports at the same time. In the All row when  
you select Ignore, Enable or Disable in one of these columns, it  
applies to all of the AT-GS950/10PS switch ports.  
Trunk - This parameter indicates the trunk group number. A  
number in this column indicates that the port has been added to a  
trunk. This parameter can not be configured on this page,  
However, for information about configuring a trunk, refer to Chapter  
Type - This parameter indicates the port type. On the  
AT-GS950/10PS, the port type is 1000TX for 10/100/1000Base-T  
twisted-pair ports (1 through 8, 9R and 10R) and 100FX or 1000TX  
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Chapter 3: Port Configuration  
for the SFP ports (9 and 10) for copper or fiber SFP type.  
Link Status - This parameter indicates the status of the link  
between the port and the end node connected to the port. The  
possible values are:  
Up -This parameter i Indicates a valid link exists between the  
port and the end node.  
Down -This parameter i Indicates the port and the end node  
have not established a valid link.  
Admin. Status -This parameter indicates the operating status of  
the port. You can use this parameter to enable or disable a port.  
You may want to disable a port and prevent packets from being  
forwarded if a problem occurs with the node or cable connected to  
the port. You can enable the port to resume normal operation after  
the problem has been fixed. You can also disable an unused port  
to secure it from unauthorized connections. The possible values  
are:  
Ignore -This parameter applies to the All row only and i  
Indicates that the Admin. Status field must be set individually  
for each port.  
Enabled - This parameter indicates the port is able to send and  
receive Ethernet frames.  
Disabled - This parameter indicates the port is not able to send  
and receive Ethernet frames.  
Jumbo -This parameter i Indicates whether or not jumbo frames  
can be accepted by the switch. You may want to activate jumbo  
frames when your switch will transmit video and audio files. The  
possible values are:  
Ignore -This parameter i Indicates that the All setting does not  
apply to the Jumbo field. In other words, each port is set  
individually.  
Enabled -This parameter i Indicates the port is permitted to  
accept jumbo frames.  
Disabled -This parameter i Indicates the port is not permitted to  
accept jumbo frames.  
Note  
When QoS is enabled on a port, the Jumbo frame parameter can  
not be enabled. To enable or disable QoS, see “Mapping CoS  
Mode -This parameter i Indicates the speed and duplex mode  
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AT-GS950/10PS Switch Web Interface User’s Guide  
settings for the port. You can use this parameter to set the speed  
and duplex mode of a port. The possible settings are:  
Ignore -This parameter i Indicates that the All setting does not  
apply to the Mode field. In other words, each port is set  
individually.  
Auto -This parameter i Indicates the port is using Auto-  
Negotiation to set the operating speed and duplex mode. The  
actual operating speed and duplex mode of the port are  
displayed in parentheses (for example, “1000F” for 1000 Mbps  
full duplex mode) after a port establishes a link with an end  
node.  
Auto (1000F) -This parameter i Indicates the port is configured  
for 1000Mbps operation in Auto-Negotiation mode.  
1000/Full -This parameter i Indicates the port is configured for  
1000Mbps operation in full-duplex mode.  
100/Full -This parameter i Indicates the port is configured for  
100Mbps operation in full-duplex mode.  
10/Full -This parameter i Indicates the port is configured for  
10Mbps operation in full-duplex mode.  
1000/Half -This parameter i Indicates the port is configured for  
1000Mbps operation in half-duplex mode.  
100/Half -This parameter i Indicates the port is configured for  
100Mbps operation in half-duplex mode.  
10/Half -This parameter i Indicates the port is configured for  
10Mbps operation in half-duplex mode.  
When selecting a Mode setting, the following points apply:  
When a twisted-pair port is set to Auto-Negotiation, the  
end node should also be set to Auto-Negotiation to  
prevent a duplex mode mismatch. A switch port using  
Auto-Negotiation defaults to half-duplex if it detects  
that the end node is not using Auto-Negotiation. This  
can result in a mismatch if the end node is operating at  
a fixed duplex mode of full-duplex. To avoid this  
problem when connecting an end node with a fixed  
duplex mode of full-duplex to a switch port, disable  
Auto-Negotiation on the port and set the port’s speed  
and duplex mode manually.  
The only valid setting for the SFP ports is Auto-  
Negotiation.  
Flow Control - This parameter reflects the current flow control  
setting on the port. The switch uses a special pause packet to  
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Chapter 3: Port Configuration  
notify the end node to stop transmitting for a specified period of  
time. The possible values are:  
Ignore - This parameter indicates that the All setting does not  
apply to the Flow Control field. In other words, each port is set  
individually.  
Enabled - This parameter indicates that the port is permitted to  
use flow control.  
Disabled - This parameter indicates that the port is not  
permitted to use flow control.  
EAP Pass - This parameter reflects the current Extensible  
Authentication Protocol (EAP) setting on the port. The possible  
values are:  
Ignore - This parameter indicates that the All setting does not  
apply to the EAP Pass field. In other words, each port is set  
individually.  
Enabled - This parameter indicates that the port is able to send  
and receive EAP packets.  
Disabled - This parameter indicates that the port is disabled  
and is not able to send or receive EAP packets.  
BPDU - This parameter reflects the current BPDU setting on the  
port.The possible values are:  
Ignore - This parameter indicates that the All setting does not  
apply to the BPDU field. In other words, each port is set  
individually.  
Enabled - This parameter indicates that the switch will pass  
BPDU frames through the switch and broadcast them through  
all other ports.  
Disabled - This parameter indicates that the switch will not pass  
BPDU frames through the switch, With RSTP or STP enabled,  
the switch will receive BPDU frames and process them  
according to the spanning tree protocol.  
3. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 4  
STP and RSTP  
This chapter provides background information about the Spanning Tree  
Protocol (STP) and the Rapid Spanning Tree Protocol (RSTP). In addition,  
there are procedures to configure STP and RSTP. The sections in the  
chapter include:  
For detailed information about STP, refer to IEEE Std 802.1D. For detailed  
information about RSTP, refer to IEEE Std 802.1w.  
Note  
To permanently save your new settings or any changes to the  
configuration file, select Save Configuration to Flash from the main  
menu on the left side of the page.  
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Chapter 4: STP and RSTP  
Overview  
The performance of a Ethernet network can be negatively impacted by the  
formation of a data loop in the network topology. A data loop exists when  
two or more nodes on a network can transmit data to each other over  
more than one data path. The problem that data loops pose is that data  
packets can become caught in repeating cycles, referred to as broadcast  
storms, that needlessly consume network bandwidth and can significantly  
reduce network performance.  
STP and RSTP prevent data loops from forming by ensuring that only one  
path exists between the end nodes in your network. Where multiple paths  
exist, these protocols place the extra paths in a standby or blocking mode,  
leaving only one main active path.  
In addition, STP and RSTP can activate a redundant path if the main path  
goes down. So not only do these protocols guard against multiple links  
between segments and the risk of broadcast storms, but they can also  
maintain network connectivity by activating a backup redundant path in  
case a main link fails.  
Where the two protocols differ is in the time each takes to complete the  
process referred to as convergence. When a change is made to the  
network topology, such as the addition of a new bridge, a spanning tree  
protocol must determine whether there are redundant paths that must be  
blocked to prevent data loops, or activated to maintain communications  
between the various network segments. This is the process of  
convergence.  
With STP, convergence can take up to a minute or more to complete in a  
large network. This can result in the loss of communication between  
various parts of the network during the convergence process, and the  
subsequent lost of data packets.  
RSTP is much faster. It can complete a convergence in seconds, and so  
greatly diminish the possible impact the process can have on your  
network. The STP implementation in the AT-S110 Management software  
complies with the IEEE 802.1d standard.  
Only one spanning tree at a time can be active on the switch. The default  
protocol is RSTP. The RSTP implementation complies with the IEEE  
802.1w standard.  
The following subsections provide a basic overview on how STP and  
RSTP operate and define the different parameters that you can adjust.  
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Bridge Priority The first task that bridges perform when a spanning tree protocol is  
activated on a network is the selection of a root bridge. A root bridge  
distributes network topology information to the other network bridges and  
is used by the other bridges to determine if there are redundant paths in  
and the Root  
Bridge  
the network.  
A root bridge is selected by the bridge priority number, also referred to as  
the bridge identifier, and sometimes the bridge’s MAC address. The bridge  
with the lowest bridge priority number in the network is selected as the root  
bridge. If two or more bridges have the same lowest bridge priority  
number, the one with the lowest MAC address is designated as the root  
bridge.  
You can change the bridge priority number in the AT-S110 Management  
software. You can designate which switch on your network as the root  
bridge by giving it the lowest bridge priority number. You may also  
consider which bridge should function as the backup root bridge in the  
event you need to take the primary root bridge off line and assign that  
bridge the second lowest bridge identifier number.  
The bridge priority has a range 0 to 61440 in increments of 4096. To make  
this easier for you, the AT-S110 Management software divides the range  
into increments. You specify the increment that represents the desired  
bridge priority value. The range is divided into sixteen increments, as  
shown in Table 1.  
Table 1 Bridge Priority Value Increments  
Bridge  
Priority  
Bridge  
Priority  
Increment  
Increment  
0x0000  
0x1000  
0x2000  
0x3000  
0x4000  
0x5000  
0x6000  
0x7000  
0
0x8000  
0x9000  
0xA000  
0xB000  
0xC000  
0xD000  
0xE000  
0xF000  
32768  
36864  
40960  
45056  
49152  
53248  
57344  
61440  
4096  
8192  
12288  
16384  
20480  
24576  
28672  
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Chapter 4: STP and RSTP  
Path Costs and Port Costs  
After the root bridge has been selected, the bridges determine if the  
network contains redundant paths and, if one is found, select a preferred  
path while placing the redundant paths in a backup or blocking state.  
Where there is only one path between a bridge and the root bridge, the  
bridge is referred to as the designated bridge and the port through which  
the bridge is communicating with the root bridge is referred to as the root  
port.  
If redundant paths exist, the bridges that are a part of the paths must  
determine which path is the primary, active path, and which path(s) are  
placed in the standby, blocking mode. This is accomplished by an  
determination of path costs. The path offering the lowest cost to the root  
bridge becomes the primary path and all other redundant paths are placed  
into blocking state.  
Path cost is determined by evaluating port costs. Every port on a bridge  
participating in STP has a cost associated with it. The cost of a port on a  
bridge is typically based on port speed. The faster the port, the lower the  
port cost. The exception to this is the ports on the root bridge, where all  
ports have a port cost of 0.  
Path cost is the sum of the port costs between a bridge and the root  
bridge.  
The port cost of a port on the switch is adjustable through the AT-S110  
Management software. For STP and RSTP, the range is from 0 to  
200,000,000.  
Port Priority  
If two paths have the same port cost, the bridges must select a preferred  
path. In some instances this can involve the use of the port priority  
parameter which is used as a tie breaker when two paths have the same  
cost.  
The range for port priority is 0 to 240. As with bridge priority, this range is  
broken into increments, in this case multiples of 16. To select a port  
priority for a port, you enter the desired value. Table 2 on page 65 lists the  
values that are valid.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
.
Table 2. Valid Port Priority Values  
Port  
Priority  
Step  
1
2
0
16  
3
32  
4
48  
5
64  
6
80  
7
96  
8
112  
128  
144  
160  
176  
192  
208  
224  
240  
9
10  
11  
12  
13  
14  
15  
16  
Forwarding If there is a change in the network topology due to a failure, removal, or  
addition of any active components, the active topology also changes. This  
may trigger a change in the state of some blocked ports. However, a  
change in a port state is not activated immediately.  
Delay and  
Topology  
Changes  
It may take time for the root bridge to notify all bridges that a topology  
change has occurred, especially if it is a large network. A temporary data  
loop could occur if a topology change is made before all bridges have  
been notified and that could adversely impact network performance.  
To forestall the formation of temporary data loops during topology  
changes, a port designated to change from blocking to forwarding passes  
through two additional states - listening and learning - before it begins to  
forward frames. The amount of time a port spends in these states is set by  
the forwarding delay value. This value states the amount of time that a port  
spends in the listening and learning states prior to changing to the  
forwarding state.  
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Chapter 4: STP and RSTP  
The forwarding delay value is adjustable in the AT-S110 Management  
software. The appropriate value for this parameter depends on a number  
of variables; the size of your network is a primary factor. For large  
networks, you should specify a value large enough to allow the root bridge  
sufficient time to propagate a topology change throughout the entire  
network. For small networks, you should specify a smaller value so that  
the time for a topology change is optimized for minimum data loss.  
Note  
The forwarding delay parameter applies only to ports on the switch  
that are operating STP-compatible mode.  
Hello Time and Bridge Protocol Data Units (BPDU)  
The bridges that are part of a spanning tree domain communicate with  
each other using a bridge broadcast frame that contains a special section  
devoted to carrying STP or RSTP information. This portion of the frame is  
referred to as the bridge protocol data unit (BPDU). When a bridge is  
brought online, it issues a BPDU in order to determine whether a root  
bridge has already been selected on the network, and if not, whether it has  
the lowest bridge priority number of all the bridges and should therefore  
become the root bridge.  
The root bridge periodically transmits a BPDU to determine whether there  
have been any changes to the network topology and to inform other  
bridges of topology changes. The frequency with which the root bridge  
sends out a BPDU is called the hello time. This is a value that you can set  
in the AT-S110 Management software. The interval is measured in  
seconds. Consequently, if the switch is selected as the root bridge of a  
spanning tree domain, it transmits a BPDU every two seconds.  
Point-to-Point and Edge Ports  
This section applies only to RSTP. Part of the task of configuring RSTP is  
defining the port types on the bridge, which is directly related to the  
device(s) connected to the port. With the port types defined, RSTP can  
reconfigure a network much quicker than STP when a change in network  
topology is detected.  
There are two possible selections:  
Point-to-point port  
Edge port  
If a bridge port is connected to another bridge or router port, it normally  
operates in full-duplex mode and is functioning as a point-to-point port.  
Figure 17 on page 67 illustrates two switches that are connected with one  
data link. This link is operating between two point-to-point ports.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
Point-to-Point Ports  
Figure 17. Point-to-Point Ports  
A port operates as an edge port when it is connected to a network terminal  
device such as a workstation or a server. An edge port on a bridge should  
not have any STP or RSTP devices connected to it either directly or  
through another device connected to that port. In this configuration since  
the port has no STP or RSTP devices connected to it, it will always forward  
network traffic. Figure 18 illustrates a port functioning as an edge port.  
Edge Port  
Workstation  
Figure 18. Edge Port  
Mixed STP and RSTP IEEE 802.1w is fully compliant with STP IEEE 802.1d. Your network  
can consist of bridges running both protocols. STP and RSTP in the same  
network can operate together to create a single spanning tree domain.  
RSTP Networks  
If you decide to activate spanning tree on the switch, Allied Telesis  
recommends RSTP instead of STP even when all of other switches in the  
network are running STP. The AT-GS950/10PS switch can combine RSTP  
with the STP of the other switches. The switches monitors the traffic on  
each port for BPDU packets. Ports that receive RSTP BPDU packets  
operate in RSTP mode while ports receiving STP BPDU packets operate  
in STP mode.  
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Chapter 4: STP and RSTP  
Spanning Tree The spanning tree implementation in the AT-S110 Management software  
can be a single-instance spanning tree as described in this chapter. If you  
choose to define multiple spanning trees on this switch, go to Chapter 5,  
and VLANs  
The single spanning tree encompasses all ports on the switch. If the ports  
are divided into different VLANs, the spanning tree crosses the VLAN  
boundaries. This can pose a problem in networks containing multiple  
VLANs that span two bridges and are connected with untagged ports. In  
this situation, spanning tree blocks a data link because it detects a  
suspected data loop. This can cause fragmentation of your VLANs.  
This issue is illustrated in Figure 42. VLANs 1 – 3 span two switches. One  
link consisting of untagged ports connect each VLAN. If STP or RSTP is  
activated on the switches, two of the links are disabled. As a direct result,  
two VLANs are disconnected between the bridges. In this example, the  
ports (on the non-root switch) that link the two parts of the VLANs 2 - 3 are  
changed to the blocking state, which disrupts these VLAN connections.  
U
U
U
U
U
U
Ports blocked by STP  
Blocked Data Links  
Figure 19. STP and VLAN Fragmentation with Untagged Ports  
You can avoid this problem by connecting the switches using tagged  
instead of untagged ports when you plan to have STP or RSTP enabled  
on your network. If each port connecting the two bridges is a tagged  
member of all three VLANs, then traffic for each of the VLANs can still flow  
through one the data links if the other two are blocked by Spanning Tree.  
The second and third data links act as redundant links in case the primary,  
unblocked data link becomes disabled. See Figure 20 for an example of  
this solution.  
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VLAN VLAN VLAN  
1-3  
1-3  
1-3  
T
T
T
Ports blocked by STP  
Blocked Data Links  
T
T
T
VLAN VLAN VLAN  
1-3 1-3 1-3  
Figure 20. STP and VLAN Compatibility with Tagged Ports  
Note  
For information about tagged and untagged ports, refer to Chapter  
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Chapter 4: STP and RSTP  
Basic STP and RSTP Configuration  
To configure the basic STP and RSTP settings, perform the following  
procedure:  
1. From the main menu on the left side of the page, select Bridge.  
The Bridge folder expands.  
2. From the Bridge folder, select the Spanning Tree folder.  
The Spanning Tree folder expands.  
3. From the Spanning Tree folder, select the RSTP folder.  
The RSTP folder expands.  
4. Form the RSTP folder, select RSTP.  
The Rapid Spanning Tree Configuration Page is displayed. See Figure  
Figure 21. Rapid Spanning Tree Configuration Page  
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The RSTP Configuration page allows you to configure basic STP  
(STP-Compatible) or RSTP protocols as well as to view current  
settings of the feature.  
In the upper portion of the page, you can set the  
following parameters:  
Global RSTP Status - Set this field to activate or de-activate the  
RSTP feature on the switch. From the Global RSTP Status field at  
the top of the page, select one of the following choices from the  
pull-down menu:  
Enable - The RSTP feature is active. The other parameter fields  
on the web page become active and are eligible for data to be  
entered.  
Disable - The RSTP feature is inactive. The other parameter  
fields on the web page become inactive and are greyed out so  
that data cannot be entered.  
Protocol Version - Set this field to activate RSTP or STP on the  
switch. To activate this field, select RSTP or STP-compatible and  
then click Apply at the top of the page.  
In the middle section of the page, the following fields  
are listed:  
Note  
You cannot change these fields.  
Root Port - The active port on the switch that is communicating  
with the root bridge. If the switch is the root bridge for the LAN,  
then there is no root port and the root port parameter is set to 0.  
Root Path Cost - The sum of all the root port costs of all the  
bridges between the switch’s root port and the root bridge including  
the switch’s root port cost.  
Time Since Topology Change - The time in seconds since the  
last topology change took place. When RSTP detects a change to  
the LAN’s topology or when the switch is rebooted, this parameter  
is reset to 0 seconds and begins incrementing until the next  
topology change is detected.  
Note  
To update the Time Since Topology Change parameter, you must  
refresh your browser.  
Topology Change Count - An integer that reflects the number of  
times RSTP has detected a topology change on the LAN since the  
switch was initially powered on or rebooted.  
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The following parameters refer to the designated root  
bridge. You cannot change these fields.  
Designated Root - This parameter includes two fields: the root  
bridge priority and the MAC address of the root bridge. For  
example, 1000 00C08F1211BB shows the root bridge priority as  
1000, and 00C08F1211BB as the MAC address.  
Hello Time - This parameter is the Hello Me. See “Hello Time and  
affects only the root bridge.  
Maximum Age - The parameter displays the maximum amount of  
time that BPDU’s are stored before being deleted on the root  
bridge.  
Forward Delay - The parameter displays the time interval between  
generating and sending configuration messages by the root bridge.  
The bottom section of the web page provides  
information about the bridge. The following parameters  
appear in the bottom third of the web page:  
Bridge ID - The Bridge ID is the MAC address of the bridge. The  
bridge identifier is used as a tie breaker in the selection of the root  
bridge when two or more bridges have the same bridge priority.  
You cannot change this parameter.  
Bridge Priority - The priority number for the bridge, in  
hexadecimal format. This number is used to determine the root  
bridge for RSTP. The bridge with the lowest priority number is  
selected as the root bridge. If two or more bridges have the same  
priority value, that is, the lowest value of all the other bridges, then  
the bridge with the numerically lowest MAC address becomes the  
root bridge. When a root bridge goes offline, the bridge with the  
lowest priority number automatically takes over as the root bridge.  
This parameter can be from 0X0000 to 0XF000, with 0XF000  
being the highest priority.  
Bridge Hello Time - This is the time interval between generating  
and sending configuration messages by the bridge. This parameter  
is active only when the switch is the root bridge.  
Bridge Maximum Age - The length of time after which stored  
bridge protocol data units (BPDU’s) are deleted by the bridge.  
Bridge Forward Delay - This is the time interval between  
generating and sending configuration messages by the bridge.  
5. Once you have configured the parameters, click Apply.  
6. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Configure RSTP Port Settings  
This section contains the following topics:  
Configure the To configure the basic RSTP port settings, perform the following  
procedure:  
Basic RSTP Port  
Settings  
1. From the main menu on the left side of the page, select Bridge.  
The Bridge folder expands.  
2. From the Bridge folder, select the Spanning Tree folder.  
The Spanning Tree folder expands.  
3. From the Spanning Tree folder, select the RSTP folder.  
The RSTP folder expands.  
4. From the RSTP folder, select the RSTP Basic Port.  
The AT-GS950/10PS RSTP Basic Port Configuration Page is  
displayed. See Figure 22 for a partial view of this page.  
Figure 22. AT-GS950/10PS RSTP Basic Port Configuration Page  
This page displays the following information about the ports:  
Port - Indicates ports 1 through 10 on the AT-GS950/10PS switch.  
You can select the All row to apply the same setting to all ports of  
your switch for the STP Status, Priority, and Path Cost fields.  
Trunk - Indicates the trunk assignment of a port.  
Link Status - Indicates if the port link status is active (Up) or  
inactive (Down).  
Port State - Indicates one of the following port states:  
Blocking - A blocking state does not allow network traffic to be  
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Chapter 4: STP and RSTP  
sent or received on a the port except for BPDU data. A port with  
a higher path cost to the root bridge than another on the switch  
will cause a switching loop and is placed in the blocking state by  
the Spanning Tree algorithm. The port’s state may change to  
the forwarding state if the other links in use fail and the  
Spanning Tree algorithm determines the port may transition to  
the forwarding state.  
Listening - This state occurs on a port during the convergence  
process. The port in the listening state processes BPDUs and  
awaits new information that would cause the port to return to the  
blocking state.  
Learning - While the port does not yet forward frames (packets)  
in this state, the port does learn source addresses from frames  
received and adds them to the filtering (switching) database.  
Forwarding - A port that both receives and sends data. This  
indicates normal operation. STP continues to monitor the port  
for incoming BPDUs that indicate the port should return to the  
blocking state to prevent a loop.  
Disabled - This state is not strictly part of STP. However, a  
network administrator can manually disable a port.  
Role - Indicates one of the following port roles:  
Disabled - The Disabled Port role is assigned if the port is not  
operational or is excluded from the active topology by  
management or it is a network access port (IEEE Std 802.1X)  
and it is Unauthorized, or its Administrative Bridge Port state is  
Disabled.  
Root - If the least cost path to the root is through this port, then  
it becomes the root port for this bridge.  
Designated - If this is the designated bridge for the LAN and if  
the root path cost information received on this port is greater  
than the root port's path cost and less than any other port's  
received information, then this port becomes the designated  
port.  
Backup - Any operational Bridge Port that is not a Root or  
Designated Port is a Backup Port if the Bridge is the Designated  
Bridge for the attached LAN.  
Alternate - Any operational Bridge Port that is not a Root or  
a Designated Port is an Alternate Port if that Bridge is not the  
Designated Bridge for the attached LAN.  
STP Status - Indicates if spanning tree protocol (either RSTP or  
STP-Compatible) is active or not on the port. Select one of the  
following choices from the pull-down menu:  
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Enable - The spanning tree protocol (both RSTP or STP-  
Compatible) is enabled on the port.  
Disabled - The spanning tree protocol (both RSTP or STP-  
Compatible) is disabled on the port.  
Priority - Indicates the port priority. See “Port Priority” on page 64  
for more information.  
Path Cost - Indicates the Path Cost assigned to each port. For  
STP, the range is from 0 to 65,535. For RSTP, the range is from  
5. Click Apply for the port you are configuring.  
6. To configure all of the ports to the same settings, in the All row,  
configure one, two, or all of the following settings: STP Status,  
Priority and Port Cost.  
7. Click Apply.  
8. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
Configure the To configure the advanced RSTP port settings, perform the following  
procedure:  
Advanced RSTP  
Port Settings  
1. From the main menu on the left side of the page, select Bridge.  
The Bridge folder expands.  
2. From the Bridge folder, select the Spanning Tree folder.  
The Spanning Tree folder expands.  
3. From the Spanning Tree folder, select the RSTP folder.  
The RSTP folder expands.  
4. From the RSTP folder, select RSTP Advanced Port folder.  
The AT-GS950/10PS RSTP Advanced Port Configuration Page is  
displayed. See Figure 23 on page 75 for a partial view of this page.  
Figure 23. AT-GS950/10PS RSTP Advanced Port Configuration Page  
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Chapter 4: STP and RSTP  
This page displays the following information about the ports:  
Port - Indicates ports 1 through 10 on the AT-GS950/10PS switch.  
You can select the All row to apply the same setting to all ports of  
your switch for the AdminOperEdge, Admin/OperPtoP, and  
Migration fields.  
Trunk - Indicates the trunk assignment of a port.  
Link - Indicates that the port’s link is active (Up) or inactive  
(Down).  
State - Indicates one of the following port states:  
Blocking - A blocking state does not allow network traffic to be  
sent or received on a the port except for BPDU data. A port with  
a higher path cost to the root bridge than another on the switch  
causes a switching loop and is placed in the blocking state by  
the Spanning Tree algorithm. The port’s state may change to  
the forwarding state if the other links in use fail and the  
Spanning Tree algorithm determines the port may transition to  
the forwarding state.  
Listening - This state occurs on a port during the convergence  
process. The port in the listening state processes BPDUs and  
awaits new information that would cause the port to return to the  
blocking state.  
Learning - While the port does not yet forward frames  
(packets), in this state the port does learn source addresses  
from frames received and adds them to the filtering (switching)  
database.  
Forwarding - A port that both receives and sends data. This  
indicates normal operation. STP continues to monitor the port  
for incoming BPDUs that indicate the port should return to the  
blocking state to prevent a loop.  
Disabled - This state is not strictly part of STP. However, a  
network administrator can manually disable a port.  
Role - Indicates one of the following port roles:  
Disabled - The Disabled Port role is assigned if the port is not  
operational or is excluded from the active topology by  
management or it is a network access port (IEEE Std 802.1X)  
and it is Unauthorized, or its Administrative Bridge Port state is  
Disabled.  
Root - If the least cost path to the root is through this port, then  
it becomes the root port for this bridge.  
Designated - If this is the designated bridge for the LAN and if  
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this port receives root path cost information that is greater than  
the root port's path cost and less than any other port's received  
information, then this port becomes the designated port.  
Backup - Any operational Bridge Port that is not a Root or  
Designated Port is a Backup Port if the Bridge is the Designated  
Bridge for the attached LAN.  
Alternate - Any operational Bridge Port that is not a Root or  
a Designated Port is an Alternate Port if that Bridge is not the  
Designated Bridge for the attached LAN.  
Admin/OperEdge - Indicates if a port is connected to an edge  
device in the network topology or not.  
True - The port is connected to an edge device and the port will  
always be in a forwarding state.  
False - The port is not connected to an edge device.  
Admin/OperPtoP - Indicates if the port is connected to another  
network device (point-to-point) in the network topology.  
True - The port is connected to a network device in the network  
topology.  
False - The port is not connected to a network device in the  
network topology.  
Migration - Indicates if the port is configured to accept RSTP and  
STP BPDUs  
5. Click Apply for the port you are configuring.  
6. To configure all of the ports to the same settings, in the All row,  
configure one, two, or all of the following settings: Admin/OperEdge,  
Admin/OperPtoP, and Migration.  
7. Click Apply.  
8. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 4: STP and RSTP  
Spanning Tree Topology  
To view the current spanning tree topology, perform the following  
procedure:  
1. From the main menu on the left side of the page, select Bridge.  
This folder expands.  
2. From the Bridge folder, select the Spanning Tree folder.  
3. From the Spanning Tree folder, select Topology Info.  
The AT-GS950/10PS Designated Topology Information Page is  
displayed. See Figure 24 for a partial view of this page.  
Figure 24. AT-GS950/10PS Designated Topology Information Page  
This page is contains status information only and there are no  
parameters to configure. The following information is displayed about  
the ports:  
Port - Indicates ports 1 through 10 on the AT-GS950/10PS switch.  
Trunk - The trunk of which the port is a member.  
Link Status - Whether the link on the port is up or down.  
Designated Root - The designated root bridge to which the  
switch’s root port is actively connected.  
Designated Cost - The sum of all the root port costs on all  
bridges, including the switch, between the switch and the root  
bridge.  
Designated Bridge - An adjacent bridge to which the root port of  
the switch is actively connected.  
Designated Port - The root bridge to which the root port of the  
switch is actively connected.  
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Chapter 5  
Multiple Spanning Tree Protocol  
This chapter provides the procedures for configuring Multiple Spanning  
Tree Protocol (MSTP). You can find an overview and configuration  
guidelines for this feature in “MSTP Overview” on page 349.  
When you configure MSTP, the information should be entered in order on  
the following web pages:  
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Chapter 5: Multiple Spanning Tree Protocol  
Multiple Spanning Tree Configuration  
To configure the MSTP settings, perform the following procedure:  
1. From the main menu on the left side of the page, select Bridge.  
The Bridge folder expands.  
2. From the Bridge folder, select the Spanning Tree folder.  
The Spanning Tree folder expands.  
3. From the Spanning Tree folder, select the MSTP folder.  
The MSTP folder expands.  
4. From the MSTP folder, select MSTP.  
The Multiple Spanning Tree Configuration Page is displayed. See  
Figure 25. Multiple Spanning Tree Configuration Page  
The MSTP Configuration page allows you to configure the MSTP  
parameters as well as to view current settings of the feature.  
In the upper portion of the page, you can set the  
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following parameters:  
Global MSTP Status - Set this field to Enable or Disable the  
MSTP feature on the switch. The Global MSTP Status must be set  
to Enable before the other MSTP configuration parameters can be  
set.  
Note  
Both RSTP and BPDU Passthrough must be disabled before you  
enable MSTP.  
Caution  
Enabling or disabling MSTP causes the switch to temporarily stop  
switching Ethernet network traffic.  
Maximum MST Instances - This specifies the maximum number  
of Multiple Spanning Tree Instances (MSTIs) that can be  
configured. The range is 1 - 31.  
Bridge Priority - This parameter specifies the priority used in  
determining the regional root for a particular MSTI. For more  
information about Bridge Priority, see Table 11 on page 360.  
Region Name - This parameter specifies the region’s name where  
the bridge is a member. This name must be identical to the  
regional names specified on other switches in the same MSTP  
more information.  
Region Revision - The parameter indicates the region’s revision  
and must be identical to the regional names specified on other  
switches in the same MSTP region. See “Multiple Spanning Tree  
Regions” on page 358 for more information.  
Dynamic Path Cost Calculation - This parameter is either True or  
False. When set to True, the path cost of each port on the bridge is  
dynamically calculated based on the port speed. If the parameter is  
set to False, the path cost of the bridge is based on the initial value  
of the port speed.  
In the middle section of the page, the status of the  
MSTP bridge parameters are shown. The bottom  
section of the page is where you can adjust the values  
of these parameters. The following fields are listed:  
Maximum Age - The Maximum Age defines the amount of time a  
port will wait for STP/RSTP information. MSTP uses this parameter  
when interacting with STP/RSTP domains on the boundary ports.  
Its range is 6 - 40 seconds.  
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Forward Delay - The Forward Delay defines the time that the  
bridge spends in the listening and learning states. Its range is  
4 - 30 seconds.  
Maximum Hop Count - The Maximum Hop Count is a parameter  
set in a BPDU packet when it originates. It is decremented by 1  
each time it is retransmitted by the next bridge. When the Hop  
Count value reaches zero, the bridge drops the BPDU packet. Its  
range is 6 - 40 hops.  
Transmit Hold Count - The Transmit Hold Count specifies the  
maximum number of BPDUs that the bridge can send per second.  
Its range is 1 - 10.  
5. Once you have configured the parameters, click Apply.  
6. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Port Configuration  
To configure the MSTP parameters for each of the ports, perform the  
following procedure:  
1. From the main menu on the left side of the page, select Bridge.  
The Bridge folder expands.  
2. From the Bridge folder, select the Spanning Tree folder.  
The Spanning Tree folder expands.  
3. From the Spanning Tree folder, select the MSTP folder.  
The MSTP folder expands.  
4. From the MSTP folder, select MSTP Port Configuration.  
The AT-GS950/10PS MSTP Port Configuration Page is displayed. See  
Figure 26 for a partial view of this page.  
Figure 26. AT-GS950/10PS MSTP Port Configuration Page  
You may choose a port and configure its MSTP parameters on this  
page. The following information is displayed:  
Port - Indicates ports 1 through 10 on the AT-GS950/10PS switch.  
You can select the All row to apply the same setting to all ports of  
your switch for the Point-to-Point Status, Edge Port, MSTP  
Status, Protocol Migration, AutoEdge Status, Restricted Role,  
Restricted TCN fields.  
Path Cost - Specifies the cost of a port to the root.  
Priority - Specifies the spanning tree port priority.  
PointToPoint Status - Indicates if the port is connected to another  
network device (point-to-point) in the network topology. See “Point-  
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ForcedTrue - The port is connected to a network device in the  
network topology.  
ForcedFalse - The port is not connected to a network device in  
the network topology.  
Auto - The switch will automatically determine the port type.  
Edge Port - Indicates if a port is connected to an edge device in  
on page 66 for more information.  
True - The port is connected to an edge device and the port will  
always be in a forwarding state.  
False - The port is not connected to an edge device.  
MSTP Status - Indicates if MSTP is Enabled or Disabled.  
Enabled - MSTP is active on the port.  
Disabled - MSTP is inactive on the port.  
Protocol Migration - A switch running MSTP supports a built-in  
protocol migration mechanism that enables it to inter-operate with  
legacy 802.1D switches.  
True - The switch is able to inter-operate with 802.1D BPDU  
packets.  
False - This switch can only operate with RSTP and MSTP  
packets.  
Hello Time - The Hello Time is frequency with which the root  
AutoEdge Status - This parameter allows the switch to detect if  
the port functioning as an edge port.  
Restricted Role - This parameter prevents the port from becoming  
a root port.  
True - The port is prevented from being a root port or a port that  
is used to communicate with the root bridge.  
False - This switch can only operate with RSTP and MSTP  
packets.  
The net effect of setting all ports on the switch to True is that it  
forces the switch into the role of the root bridge regardless of other  
path costs in the network.  
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Restricted TCN - The Restricted TCN parameter does not allow  
Topology Change Notification (TCN) BPDUs to be processed on  
the port.  
True - The port cannot process receive/transmit TCN BPDUs.  
False - The port can process receive/transmit TCN BPDU  
packets.  
5. Once you have configured the parameters, click Apply in the Action  
column.  
6. If you choose to change the MSTP port configuration for other ports,  
repeat steps 4 and 5.  
7. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 5: Multiple Spanning Tree Protocol  
VLAN Mapping  
You can create, modify and delete MSTP settings with the procedures in  
the following sections:  
Open MSTP 1. From the main menu on the left side of the page, select Bridge.  
The Bridge folder expands.  
VLAN Mapping  
Page  
2. From the Bridge folder, select the Spanning Tree folder.  
The Spanning Tree folder expands.  
3. From the Spanning Tree folder, select the MSTP folder.  
The MSTP folder expands.  
4. From the MSTP folder, select MSTP VLAN Mapping.  
The MSTP VLAN Mapping Page is displayed. See Figure 27.  
Figure 27. MSTP VLAN Mapping Page  
Create VLAN 1. Enter the MSTP Instance ID. You can enter any number of MSTP IDs  
up to the maximum MSTP ID. See “Multiple Spanning Tree  
Configuration” on page 80 for more information.  
Mapping to MST  
Instance  
2. Enter an existing VLAN ID in the ADD VLAN field that you want to  
associate with the MSTI ID entered in step 4.  
3. Click Add.  
The Instance ID and the Mapped VLAN will be displayed in the table  
on the page.  
4. You may add as many VLANs to one MST Instance by repeating steps  
4 through 6.  
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5. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
Modify MST If you wish to modify a MST Instance, you must first delete the instance  
page 86 for more information.  
Instance  
Delete MST 1. In the Action column of the table, click on Delete for the MST Instance  
that want to delete.  
The instance is deleted along with the mapped associations to the  
VLANs that are listed.  
Instance  
2. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 5: Multiple Spanning Tree Protocol  
Port Settings  
To configure the MSTP port settings, perform the following procedure:  
1. From the main menu on the left side of the page, select Bridge.  
The Bridge folder expands.  
2. From the Bridge folder, select the Spanning Tree folder.  
The Spanning Tree folder expands.  
3. From the Spanning Tree folder, select the MSTP folder.  
The MSTP folder expands.  
4. From the MSTP folder, select MSTP Port Settings.  
The MSTP Port Settings Page is displayed. See Figure 28.  
Figure 28. MSTP Port Settings Page  
You may choose a port and configure its MSTP parameters on this  
page. The following information is displayed:  
Port - Indicates ports 1 through 10 on the AT-GS950/10PS switch.  
You can select the All row to apply the same settings to all ports  
on your switch for the Port State field.  
MSTP Instance ID - Indicates the MSTP Instance that associated  
with this port.  
Port State - This parameter activates or deactivates the port.  
Select one of the following choices from the pull-down menu:  
Enable - Allows the port to forward packets.  
Disable - Does not allows the port to forward packets.  
Priority - This is the port priority used by MSTP in calculating path  
costs when two ports on the switch have the same port cost.  
Cost - This is the port cost used by MSTP when calculating path  
cost to the root bridge.  
5. Once you have configured the parameters, click Apply in the Action  
column.  
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6. If you choose to change the MSTP port settings for other ports, repeat  
steps 4 and 5.  
7. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 5: Multiple Spanning Tree Protocol  
Topology Information  
To configure the MSTP port settings, perform the following procedure:  
1. From the main menu on the left side of the page, select Bridge.  
The Bridge folder expands.  
2. From the Bridge folder, select the Spanning Tree folder.  
The Spanning Tree folder expands.  
3. From the Spanning Tree folder, select the MSTP folder.  
The MSTP folder expands.  
4. From the MSTP folder, select MSTP Port Settings.  
The AT-GS950/10PS Topology Information Page is displayed. See  
A partial view of the AT-GS950/10PS Topology Information Page is  
displayed. See Figure 29.  
Figure 29. AT-GS950/10PS Topology Information Page  
The following information displayed on this page shows the current  
status of MSTP for each port:  
Port - Indicates ports 1 through 10 on the AT-GS950/10PS switch.  
Designated Root - The designated root bridge to which the  
switch’s root port is actively connected.  
Root Priority - This parameter specifies the priority used in  
determining the regional root for a particular MSTI. For more  
Designated Bridge - The bridge providing the least cost path to  
the root bridge from a network segment.  
Designated Port - The port providing the least cost path to the  
root bridge from a network segment.  
Designated Cost - The cost from the designated bridge to the root  
bridge.  
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Regional Root - The root bridge of the MST instance.  
Regional Root Priority - The priority of the regional root port.  
Regional Path Cost - The path cost from the regional root port to  
the regional root bridge.  
Type - This specifies the regional port type which can be either a  
point-to-point or an edge type port. See “Point-to-Point and Edge  
Ports” on page 66 for more information.  
Role - Indicates the port’s role which may be Disabled, Root,  
Designated, Backup, or Alternate. See the parameter definitions  
on page 73 for more information.  
Port State - Indicates the ports spanning tree state which may be  
Blocking, Listening, Learning, Forwarding, Disabled. See the  
parameter definitions described for Port State under “Configure  
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Chapter 5: Multiple Spanning Tree Protocol  
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Chapter 6  
Static Port Trunking  
This chapter contains a description of port trunking and the procedures for  
creating, modifying, and deleting a static port trunk. The following topics  
are discussed:  
Note  
For information about Link Aggregation Control Protocol (LACP) port  
trunking, see Chapter 11, “LACP Port Trunks” on page 155.  
Note  
To permanently save your new settings or any changes to the  
configuration file, select Save Configuration to Flash from the main  
menu on the left side of the page.  
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Chapter 6: Static Port Trunking  
Overview  
A port trunk is an economical way for you to increase the bandwidth  
between the Ethernet switch and another networking device, such as a  
network server, router, workstation, or another Ethernet switch. A port  
trunk is a group of ports that have been grouped together to function as  
one logical path. A port trunk increases the bandwidth between the switch  
and another network device and is useful in situations where a single  
physical link between the devices is insufficient to handle the traffic load.  
A static port trunk consists of two to eight ports on the switch that function  
as a single virtual link between the switch and another device. A static port  
trunk improves performance by distributing the traffic across multiple ports  
between the devices and enhances reliability by reducing the reliance on a  
single physical link.  
A static trunk is easy to configure. You designate the ports on the switch  
that are in the trunk and the AT-S110 Management software on the switch  
automatically groups them together.  
The example in Figure 30 illustrates a static port trunk of four links  
between two AT-GS950/10PS switches.  
Static Trunk  
Figure 30. Static Port Trunk Example  
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Network equipment vendors tend to employ different techniques to  
implement static trunks. Consequently, a static trunk on one device may  
be incompatible with the same feature on a device from a different  
manufacturer. For this reason static trunks are typically employed only  
between devices from the same vendor. That is not to say that an Allied  
Telesis Layer 2 managed switch cannot form a static trunk with a device  
from another manufacturer; however, the implementations of static  
trunking on the two devices may be incompatible.  
Also, note that a static trunk does not provide for redundancy or link  
backup. If a port in a static trunk loses its link, the trunk’s total bandwidth is  
diminished. Although the traffic carried by the lost link is shifted to one of  
the remaining ports in the trunk, the bandwidth remains reduced until the  
lost link is re-established or you reconfigure the trunk by adding another  
port to it.  
General Guidelines  
Following are the guidelines for creating a static trunk:  
Allied Telesis recommends setting static port trunks  
between Allied Telesis networking devices to ensure  
compatibility.  
A static trunk can contain up to eight ports.  
The ports of a static trunk must be of the same medium  
type. They can be all twisted-pair ports or all fiber optic  
ports, but not a combination of the two.  
The ports of a trunk can be either consecutive (for  
example, Ports 2 through 4) or nonconsecutive (for  
example, ports 3, 5, and 7).  
Before creating a port trunk, verify that the settings are  
the same for all ports in the trunk including speed  
(1000/Full), duplex mode, flow control, back pressure  
settings and VLAN membership. If these settings are  
not the same, then the switch does not allow you to  
create the trunk.  
Note  
When a trunk group is formed with only combo ports as members, all  
port members are configured to the forced port mode at 1000/Full.  
The trunk ports on the connecting network switch should also be  
configured for 1000/Full to insure speed and duplex compatibility  
between the switches.  
After you have created a port trunk, a change to the  
speed, duplex mode, flow control, or back pressure of  
any port in the trunk automatically implements the  
same change on all the other member ports.  
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Chapter 6: Static Port Trunking  
A port can belong to only one static trunk at a time.  
The ports of a static trunk can be configured to be  
members of more than one VLAN.  
The ports of a static trunk can be either untagged or  
untagged members of the same VLAN.  
The switch selects a port in the trunk to handle broadcast packets and  
packets of unknown destination. The switch makes this choice based on a  
hash algorithm, depending upon the source and destination MAC  
addresses.  
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Create a Port Trunk  
This procedure explains how to create a static port trunk.  
Caution  
Do not connect the cables of a port trunk to the ports on the switch  
until you have configured the ports on both the switch and the end  
nodes. Connecting the cables prior to configuring the ports can  
create loops in your network topology. Loops can result in broadcast  
storms which can severely limited the effective bandwidth of your  
network.  
To create a port trunk, perform the following procedure:  
1. Select the Bridge folder.  
The Bridge folder expands.  
2. From the Bridge folder, select the Trunk Config folder.  
The Trunk Config folder expands.  
3. From the Trunk Config folder, select Trunking.  
A partial view of the Trunking Page is displayed in Figure 31.  
Figure 31. Trunking Page  
If the switch does not contain a port trunk, all of the ports on the switch  
are unchecked. If there is a port trunk, the ports in the trunk are  
checked.  
4. Click the dialog boxes of the ports that will make up the port trunk.  
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Chapter 6: Static Port Trunking  
A check in a box indicates the port is a member of the trunk. No check  
means the port is not a member. A port trunk can contain up to eight  
ports.  
5. Change the Trunk Status from Disable to another setting. The choice  
in the status field are the following:  
Active - The specific aggregator will broadcast and respond to  
LACPDU (LACP Data Unit) packets. This setting enables  
the LACP feature for the trunk.  
Passive - The specific aggregator will not broadcast LACPDU  
packets, but it will respond to them. This setting disables the LACP  
feature for the trunk.  
Manual - Enables static port trunking and disables the LACP  
feature for the trunk.  
Disable - Disables the static port trunk and disables the LACP  
feature for the trunk.  
6. Click Apply.  
7. If you did not select the trunk mode Disabled, the trunk is now  
operational on the switch.  
8. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
9. Configure the port trunk on the other switch.  
10. Connect the Ethernet cables between trunk ports on the AT-GS950/  
10PS switch and the trunk ports on the other switch.  
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Modify a Port Trunk  
This procedure explains how to change the status of a port trunk and add  
or remove ports from a port trunk.  
Caution  
Before you disable or modify a port trunk, disconnect all of the  
cables from the ports of the trunk. Leaving the cables connected  
during the reconfiguration of a trunk can create loops in your  
network topology. Loops can result in broadcast storms which can  
severely limited the effective bandwidth of your network.  
To add or remove ports from a trunk, perform the following procedure:  
1. Disconnect all of the Ethernet cables from the ports of the trunk.  
2. Select the Bridge folder.  
The Bridge folder expands.  
3. From the Bridge folder, select the Trunk Config folder.  
The Trunk Config folder expands.  
4. From the Trunk Config folder, select Trunking.  
The Trunking Page is shown in Figure 31 on page 97.  
5. Click the status of the port trunk you want to modify and change the  
status to one of the following options:  
Disable - Disables the port trunk.  
Active - The aggregator will broadcast and respond to LACPDU  
(LACP Data Unit) packets. This setting enables the LACP feature.  
Passive - The aggregator will not broadcast LACPDU packets, but  
it will respond to them. This setting enables the LACP feature.  
Manual - Enables static port trunking and disables the LACP  
feature.  
6. To add or remove a port from a trunk, click the dialog box for the port in  
the corresponding trunk row.  
A check in a box indicates the port is a member of the trunk. No check  
means the port is not a member. A port trunk can contain up to eight  
ports.  
7. Click Apply.  
8. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 6: Static Port Trunking  
9. Configure the port trunk on the other switch with the same parameters.  
10. Connect the Ethernet cables between trunk ports on the AT-GS950/  
10PS switch and the trunk ports on the other switch.  
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Disable a Port Trunk  
This procedure explains how to disable a port trunk.  
Caution  
Before you disable or modify a port trunk, disconnect all of the  
cables from the ports of the trunk. Leaving the cables connected  
during the reconfiguration of a trunk can create loops in your  
network topology. Loops can result in broadcast storms which can  
severely limited the effective bandwidth of your network.  
To disable a port trunk, perform the following procedure:  
1. Disconnect all of the Ethernet cables from the ports of the trunk.  
2. Select the Bridge folder.  
The Bridge folder expands.  
3. From the Bridge folder, select the Trunk Config folder.  
The Trunk Config folder expands.  
4. From the Trunk Config folder, select Trunking.  
The Trunking Page is shown in Figure 31 on page 97.  
5. To disable a port trunk, select Disable from the pull-down menu next  
to the trunk that you want to disable.  
6. Click Apply.  
7. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
8. Modify the port trunk configuration in the same way on the other  
switch.  
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Chapter 6: Static Port Trunking  
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Chapter 7  
LACP Port Trunks  
This chapter contains overview information about LACP port trunks and  
the procedures for setting this feature. This chapter contains the following  
sections:  
Note  
For information about port trunking, see Chapter 6, “Static Port  
Note  
To permanently save your new settings or any changes to the  
configuration file, select Save Configuration to Flash from the  
main menu on the left side of the page.  
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Chapter 7: LACP Port Trunks  
Overview  
LACP (Link Aggregation Control Protocol) port trunks perform the same  
function as static trunks. They increase the bandwidth between network  
devices by distributing the traffic load over multiple physical links. The  
advantage of an LACP trunk over a static port trunk is its flexibility. While  
implementations of static trunking tend to be vendor specific, the AT-S110  
Management software implementation of LACP is compliant with the IEEE  
802.3ad standard, making it interoperable with equipment from other  
vendors that also comply with the standard. Therefore, you can create an  
LACP trunk between an Allied Telesis device and network devices from  
other manufacturers.  
Another advantage is that ports in an LACP trunk can function in a  
standby mode. This adds redundancy and resiliency to the trunk. If a link  
in a static trunk goes down, the overall bandwidth of the trunk is reduced  
until the link is re-established or another port is added to the trunk. In  
contrast, an LACP trunk can automatically activate ports in a standby  
mode when an active link fails so that the maximum possible bandwidth of  
the trunk is maintained.  
For example, assume you create an LACP trunk of ports 1 to 6 on a switch  
and the switch is using ports 1 to 4 as the active ports and ports 5 and 6 as  
reserve. If an active port loses its link, the switch automatically activates  
one of the reserve ports to maintain maximum bandwidth of the trunk.  
The main component of an LACP trunk is an aggregator which manages a  
group of ports on the switch. On the AT-GS950/10PS switch, the ports  
assigned to a trunk group are automatically assigned to an aggregator.  
Only one aggregator can be assigned to each trunk group. With LACP  
activated, each active trunk group is referred to as an aggregate trunk.  
An aggregate trunk can consist of any number of ports on a switch, but  
only a maximum of eight ports can be active at a time. If an aggregate  
trunk contains more ports than can be active at once, the extra ports are  
placed in a standby mode. Ports in the standby mode do not pass network  
traffic, but they do transmit and accept LACP Data Unit (LACPDU)  
packets, which the switch uses to search for LACP-compliant devices.  
Only ports that are part of an aggregator transmit LACPDU packets. A port  
that is part of an aggregator assumes that the other port is not part of an  
LACP trunk if it does not receive LACPDU packets from its corresponding  
port on the other device. Instead, it functions as port in standby mode and  
does not forward network traffic. However, it does continue to send  
LACPDU packets. If it begins to receive LACPDU packets, it automatically  
transitions to an active or standby mode as part of an aggregate trunk.  
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System Priority  
It is possible for two devices interconnected by an aggregate trunk to  
encounter a conflict when they form the trunk. For example, the two  
devices might not support the same number of active ports in an  
aggregate trunk or might not agree on which ports are active and which  
are in standby mode.  
If a conflict does occur, the two devices need a mechanism for resolving  
the problem and deciding whose LACP settings take precedence. This is  
the function of the system LACP priority value. This value is used  
whenever the devices encounter a conflict creating a trunk - the lower the  
number, the higher the priority. As a result, the settings on the device with  
the higher priority take precedence over the settings on the other device. If  
both devices have the same system LACP priority value, the settings on  
the switch with the lowest MAC address take precedence. In the AT-S110  
Management software, the MAC address is called the System ID.  
The LACP System Priority is pre-assigned and you cannot alter this  
parameter.  
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Chapter 7: LACP Port Trunks  
Port Priority Value  
The switch uses a port’s LACP priority to determine which ports are active  
and which are in the standby mode in situations where the number of ports  
in the aggregate trunk exceeds the highest allowed number of active  
ports. This parameter is a value in a range of 1 to 255, based on the port  
number. For instance, the priority values for ports 2 and 11 are 002 and  
011, respectively. The lower the number, the higher the priority. Ports with  
the highest priorities are designated as the active ports in an aggregate  
trunk.  
For example, if both 802.3ad-compliant devices support up to six active  
ports and there are a total of eight ports in the trunk, the six ports with the  
highest priorities (lowest priority values) are designated as the active  
ports, and the others are placed in the standby mode. If an active link goes  
down on a active port, the standby port with the next highest priority is  
automatically activated to take its place.  
The selection of the active links in an aggregate trunk is dynamic and  
changes as links are added, removed, lost, or reestablished. For example,  
if an active port loses its link and is replaced by another port in the standby  
mode, the re-establishment of the link on the originally active port causes  
the port to return to the active state by virtue of having a higher priority  
value than the replacement port, which returns to the standby mode.  
Two conditions must be met for a port in an aggregate trunk to function in  
the standby mode. First, the number of ports in the trunk must exceed the  
highest allowed number of active ports and, second, the port must be  
receiving LACPDU packets from the other device. A port functioning in the  
standby mode does not forward network traffic. However, it continues to  
send LACPDU packets. If a port that is part of an aggregator does not  
receive LACPDU packets, it functions as a normal Ethernet port and  
forwards network packets along with LACPDU packets.  
Note  
You can adjust the value of a port’s priority.  
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General Guidelines  
The following guidelines apply when creating aggregators:  
LACP must be activated on both the AT-GS950/10PS  
switch and its partner device.  
The other device must be 802.3ad-compliant.  
The AT-S110 Management software supports up to  
eight active ports in an aggregate trunk at a time.  
The AT-GS950/10PS Gigabit Ethernet PoE+ Switch  
can support up to eight static and LACP aggregate  
trunk groups at a time (for example, four static trunks  
and four LACP trunks). An LACP trunk is counted  
against the maximum number of trunks only when it is  
active.  
The ports of an aggregate trunk must be the same  
medium type: all twisted pair ports or all fiber optic  
ports.  
The ports of a trunk can be consecutive (for example  
ports 1-5) or nonconsecutive (for example, ports 2, 4,  
6, 8).  
A port can belong to only one aggregator at a time.  
A port cannot be a member of an aggregator and a  
static trunk at the same time.  
The ports of an aggregate trunk must be untagged  
members of the same VLAN.  
Twisted pair ports must be set to Auto-Negotiation or  
1000 Mbps, full-duplex mode. LACP trunking is not  
supported in half-duplex mode.  
1000Base-X fiber optic ports must be set to full-duplex  
mode.  
You can create an aggregate trunk of transceivers with  
1000Base-X fiber optic ports.  
Only those ports that are members of an aggregator  
transmit LACPDU packets.  
A member port of an aggregator functions as part of an  
aggregate trunk only if it receives LACPDU packets  
from the remote device. If it does not receive LACPDU  
packets, it functions as a regular Ethernet port,  
forwarding network traffic while also continuing to  
transmit LACPDU packets.  
The port with the highest priority in an aggregate trunk  
carries broadcast packets and packets with an  
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Chapter 7: LACP Port Trunks  
unknown destination.  
Prior to creating an aggregate trunk between an Allied  
Telesis device and another vendor’s device, refer to  
the vendor’s documentation to determine the  
maximum number of active ports the device can  
support in a trunk. If the number is less than eight, the  
maximum number for the AT-GS950/10PS switch, you  
should assign the other vendor’s device a higher  
system LACP priority than your AT-GS950/10PS  
switch. This can help avoid a conflict between the  
devices if some ports are placed in the standby mode  
when the devices create the trunk. For background  
LACPDU packets are transmitted as untagged  
packets.  
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Group Status  
To display the LACP Group Status, perform the following procedure:  
1. Select the Bridge folder.  
The Bridge folder expands.  
2. From the Bridge folder, select the Trunk Config folder.  
The Trunk Config folder expands.  
3. From the Trunk Config folder, select LACP Group Status.  
The LACP Group Status Page is displayed. See Figure 32.  
Figure 32. LACP Group Status Page  
Note  
parameters on this page:  
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Chapter 7: LACP Port Trunks  
The System Priority is a preassigned value that you cannot alter. This  
value applies to the switch. See “System Priority” on page 105.  
The System ID is a MAC address value assigned to the individual  
switch. You cannot change this value.  
Group 1 to 8 indicates the ID number of the trunk (aggregation group).  
Configuration  
Example  
Use the procedure given in “Create a Port Trunk” on page 97 to  
configure Trunk ID 1 as Active with ports 3, 4 and 5.  
The LACP Group Status Page is updated. This configuration is shown  
in Figure 33 before the Ethernet cables are connected.  
Figure 33. LACP Group Status Page with No Cables Connected  
4. Physically connect the network cables between the switch and a  
second LACP device which is pre-configure with an LACP activated  
trunk of three or more ports.  
The LACP Group Status Page is updated. An example of these  
updates is shown in Figure 34 on page 111 after three trunking cables  
are installed and the ports have Link-Up status.  
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Figure 34. LACP Group Status Page with Three Cables Connected  
You can now see that each port has been grouped under a single  
aggregator since the ports are now in a Link-Up status.  
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Chapter 7: LACP Port Trunks  
Port Priority Configuration  
To select a priority for an LACP port, perform the following procedure:  
1. Select the Bridge folder.  
The Bridge folder expands.  
2. From the Bridge folder, select the Trunk Config folder.  
The Trunk Config folder expands.  
3. From the Trunk Config folder, select Port Priority.  
The AT-GS950/10PS Port Priority Page is displayed. See Figure 35  
for a partial view of this page.  
Figure 35. AT-GS950/10PS Port Priority Page  
The System Priority is a preassigned value that you cannot alter. This  
value applies to the switch. See “System Priority” on page 105.  
The System ID is a MAC address value assigned to the switch. You  
cannot change this value.  
4. To set the port priority, select a value from 0 to 255 in the Priority  
column for the port you want to alter. For more information, see “Port  
5. Select Apply.  
6. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 8  
Port Mirroring  
This chapter describes the Port Mirroring feature and the procedure for  
setting up port mirroring. Port mirroring allows you to unobtrusively monitor  
the ingress and egress traffic on a port by having the traffic copied to  
another port. This chapter contains the following sections:  
Note  
To permanently save your new settings or any changes to the  
configuration file, select Save Configuration to Flash from the main  
menu on the left side of the page.  
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Chapter 8: Port Mirroring  
Overview  
The port mirroring feature allows you to unobtrusively monitor the traffic  
received and transmitted on one or more ports by copying the traffic to  
another switch port. You can connect a data analyzer to the port where the  
traffic is copied and monitor the traffic on the other ports without impacting  
network performance or speed.  
A port mirror has two component ports. The port or ports whose traffic you  
want to mirror is called the source port(s). The port where the traffic will be  
copied to is called the mirroring port.  
Observe the following guidelines when you create a port mirror:  
You can select more than one source port at a time.  
However, the more ports you mirror, the less likely the  
mirroring port is able to handle all the traffic. For  
example, if you mirror the traffic of six heavily active  
ports, the destination port is likely to drop packets,  
meaning that it does not provide an accurate mirror of  
the traffic of the six source ports.  
The source and mirror ports must be located on the  
same switch.  
You can mirror the ingress or egress traffic of the  
source ports or both.  
While the Mirroring feature is enabled, the mirroring  
port is dedicated to monitoring the traffic from the  
source ports and cannot used for regular network  
operations.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
Port Mirroring Configuration  
To configure Port Mirroring, perform the following procedure:  
1. Select the Bridge folder.  
The Bridge folder expands.  
2. From the Bridge folder, select Mirroring.  
The Mirroring Page is displayed. See Figure 36.  
Figure 36. AT-GS950/10PS Mirroring Page  
3. Click the pull-down menu on the Status field and select one of the  
following choices:  
Enable - This parameter activates the Port Mirroring feature and  
the rest of the configuration parameters become active on the  
page.  
Disable - This parameter de-activates the Port Mirroring feature  
and the rest of the configuration parameters become inactive on  
the page.  
4. Click Mirroring Port and from the pull-down menu, select the port.  
5. For the source port, select the port(s) whose ingress, egress, or both  
ingress and egress traffic you want to monitor.  
A check in a box indicates the Ingress or Egress traffic for a port has  
been selected.  
6. Click Apply on the right-hand side of the page.  
The Port Mirroring configuration is implemented immediately on the  
AT-GS950/10PS switch.  
You can connect a data analyzer to the mirroring port to monitor the  
Ethernet traffic on the source port(s).  
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Chapter 8: Port Mirroring  
7. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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AT-GS950/10PS Switch Web Interface User’s Guide  
Disable Port Mirroring  
To disable Port Mirroring, perform the following procedure:  
1. Select the Bridge folder.  
The Bridge folder expands.  
2. From the Bridge folder, select Mirroring.  
3. From the Status field, select Disable and click Apply.  
Port mirroring is immediately disabled on the switch and the  
parameters on the web page become inactive. You can now use the  
mirroring port for regular network operations.  
4. From the main menu on the left side of the page, select Save  
Configuration to Flash to permanently save your changes.  
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Chapter 8: Port Mirroring  
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Chapter 9  
Loopback Protection  
This chapter explains how to configure the Loopback Protection feature for  
specific ports on the AT-GS950/10PS switch. If the Tx and Rx pairs on the  
same port are connected, then this feature detects this condition and  
disables the port for a pre-configured amount of time.  
This chapter contains the following topics:  
Note  
To permanently save your new settings or any changes to the  
configuration file, select Save Configuration to Flash from the main  
menu on the left side of the page.  
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Chapter 9: Loopback Protection  
Configuration  
To configure the Loopback Detection feature, perform the following  
procedure:  
1. From the main menu on the left side of the page, select Bridge.  
The Bridge folder expands.  
2. From the Bridge folder, select Loopback Detection.  
A partial view of the AT-GS950/10PS Loopback Detection Page is  
displayed. See Figure 37.  
Figure 37. AT-GS950/10PS Loopback Detection Page  
3. For the Loopback Detection State field a the top of the page, select  
one of the following radio buttons:  
Enabled: This selection enables the Loopback Detection feature  
across the switch. This state must be enabled for the individual  
port Loopback Detection State is effective.  
Disabled: This selection disables the Loopback Detection feature  
on the switch.  
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