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Catalyst 2960 Switch SoftwareConfiguration Guide
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Chapter5 Clustering Switches
Understanding Switch Clusters
Using switch clusters simplifies the management of multiple switches, regardless of their physical
location and platform families. Clustering also provides redundancy th rough standby cluster command
switches.
In a switch cluster, 1switch must be the cluster command switch and up to 15 other switche s can be
cluster member switches. The total number of switches in a cluster cannot exceed 16 switches. The
cluster command switch is the single point of access used to configure, manage, and monitor the cluster
member switches. Cluster members can belong to only one cluster at a time.
Note If you configure Secure Socket Layer (SSL) Version 3.0 for a secure (HTTPS) connection, the SSL
connection stops at the command switch. Cluster member switches must run nonsecure HTTP. For more
information about SSL, see the “Configuring the Switch for Secure Socket Layer HTT P” section on
page 8-37.
For more information about switch clustering, including cluste r-planning considerations, see Getting
Started with Cisco Network Assistant, available on Cisco.com. For a list of Catalyst switches eligible for
switch clustering, including which ones can be cluster command switches and which ones can only be
cluster member switches, and the required software versions, see the Release Notes for Cisco Network
Assistant, available on Cisco.com.
Cluster Command Switch Characteristics
A cluster command switch must meet these requirements:
•It is running Cisco IOS Release 12.2(25)FX or later.
•It has an IP address.
•It has Cisco Discovery Protocol (CDP) Version 2 enabled (the default).
•It is not a command or cluster member switch of another cluster.
•It is connected to the standby cluster command switches through the management VLAN and to the
cluster member switches through a common VLAN.
Note If your switch cluster has a Catalyst 2960 switch, it should be the cluster command switch unless the
cluster has a Catalyst 3750 switch or switch stack. If the switch c luster has a Catalyst 3750 switch or
switch stack, that switch or switch stack should be the cluster command switch.
Standby Cluster Command Switch Characteristics
A standby cluster command switch must meet these requirements:
•It is running Cisco IOS Release 12.2(25)FX or later.
•It has an IP address.
•It has CDP Version 2 enabled.
•It is connected to the command switch and to other standby command switches through its
management VLAN.
•It is connected to all other cluster member switches (except the cluster command and standby
command switches) through a common VLAN.