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Catalyst2950 and Catalyst2955 Switch Software Configuration Guide
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Chapter7 Clustering Switches Creating a Switch Cluster
Creating a Cluster Standby Group
The cluster standby group members must meet the requirements described in the “Standby Command
Switch Characteristics” section on page7-3 and “HSRP and Standby Command Switches” section on
page 7-11. To create a cluster standby group, select Cluster > Standby Command Switches
(Figure 7-12).
Instead of using CMS to add switches to a standby group and to bind the standby group to a cluster, you
can use the standby ip, the standby name, and the standby priority interface configuration commands
and the cluster standby group global configuration command.
•When the command switch is a Catalyst3550 switch, all standby command switches must be
Catalyst 3550 switches.
•When the command switch is a Catalyst2955 switch, all standby command switches must be
Catalyst 2955 switches.
•When the command switch is a Catalyst2940 switch, all standby command switches must be
Catalyst 2940 switches.
•When the command switch is a Catalyst2950 LRE switch, all standby command switches must be
Catalyst 2950 LRE switches.
•When the command switch is a non-LRE Catalyst 2950 switch running Cisco IOS
Release 12.1(6)EA2 or later, all standby command switches must be non-LRE Catalyst 2950
switches running Cisco IOS Release 12.1(6)EA2 or later.
•When the command switch is running Cisco IOS Release 12.0(5)WC2 or earlier, the standby
command switches can be these switches: Catalyst 2900 XL, non-LRE Catalyst 2950, and
Catalyst 3500XL switches.
These abbreviations are appended to the switch host names in the Standby Command Group list to show
their eligibility or status in the cluster standby group:
•AC—Active command switch
•SC—Standby command switch
•PC—Member of the cluster standby group but not the standby command switch
•HC—Candidate switch that can be added to the cluster standby group
•CC—Command switch when HSRP is disabled
You must enter a virtual IP address for the cluster standby group. This address must be in the same subnet
as the IP addresses of the switch. The group number must be uniq ue within the IP subnet. It can be from
0 to255, and the de fau lt i s 0. T he g rou p name c an h ave up to 3 1 characters.
The Standby Command Configuration window uses the default values for the preempt and name
commands that you have set by using the CLI. If you use this window to create the HSRP group, all
switches in the group have the preempt command enabled. You must also provide a name for the group.
Note The HSRP standby hold time interval should be greater than or equal to 3 times the hello time interval.
The default HSRP standby hold time interval is 10 seconds. The default HSRP standby hello time
interval is 3 s econds . For more info rmati on about th e standby hold time and hell o time inte rvals, refer
to the Cisco IOS Release 12.1 documentation set on Cisco.com.