Cisco Catalyst 3120 User Manual

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Cisco Catalyst Blade Switch 3120 for HP Software Configuration Guide
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Chapter 5 Managing Switch Stacks
Configuring the Switch Stack
• If you enter a time delay of 1 to 60 minutes, the stack MAC address of the previous stack master is
used until the configured time period expires or until you enter the no stack-mac persistent timer
command.
Note If the entire switch stack reloads, it uses the MAC address of the stack master as the stack MAC address.
Beginning in privileged EXEC mode, follow these steps to enable persistent MAC address. This
procedure is optional.
Use the no stack-mac persistent timer global configuration command to disable the persistent MAC
address feature.
This example shows how to configure the persistent MAC address feature for a 7-minute time delay and
to verify the configuration:
Switch(config)# stack-mac persistent timer 7
WARNING: The stack continues to use the base MAC of the old Master
WARNING: as the stack MAC after a master switchover until the MAC
WARNING: persistency timer expires. During this time the Network
WARNING: Administrators must make sure that the old stack-mac does
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
stack-mac persistent timer [0 |
time-value]
Enable a time delay after a stack-master change before the stack MAC
address changes to that of the new stack master. If the previous stack
master rejoins the stack during this period, the stack uses that MAC
address as the stack MAC address.
• Enter the command with no value to set the default delay of
approximately 4 minutes. We recommend that you always configure
a value.
• Enter 0 to continue using the MAC address of the current stack
master indefinitely.
• Enter a time-value from 1 to 60 minutes to configure the time period
before the stack MAC address changes to the new stack master.
Note When you enter this command, a warning states that traffic
might be lost if the old master MAC address appears elsewhere
in the network domain.
If you enter the no stack-mac persistent timer command after a new
stack master takes over, before the time expires, the switch stack moves
to the current stack master MAC address.
Step 3
end Return to privileged EXEC mode.
Step 4
show running-config
or
Verify that the stack MAC address timer is enabled. If enabled, the
output shows
stack-mac persistent timer and the time in minutes.
Step 5
show switch If enabled, the display includes:
Mac persistency wait time, the number of minutes configured, and
the current stack MAC address.
Step 6
copy running-config startup-config (Optional) Save your entries in the configuration file.

Cisco Catalyst 3120 Specifications

General

Brand	Cisco
Model	Catalyst 3120
Category	Switch
Language	English