Cisco Systems 3750E manual Planning a Switch Cluster

Chapter 6 Clustering Switches

Planning a Switch Cluster

Candidate Switch and Cluster Member Switch Characteristics

Candidate switches are cluster-capable switches and switch stacks that have not yet been added to a cluster. Cluster member switches are switches and switch stacks that have actually been added to a switch cluster. Although not required, a candidate or cluster member switch can have its own IP address and password (for related considerations, see the “IP Addresses” section on page 6-14and “Passwords” section on page 6-15).

To join a cluster, a candidate switch must meet these requirements:

•It is running cluster-capable software.

•It has CDP Version 2 enabled.

•It is not a command or cluster member switch of another cluster.

•If a cluster standby group exists, it is connected to every standby cluster command switch through at least one common VLAN. The VLAN to each standby cluster command switch can be different.

•It is connected to the cluster command switch through at least one common VLAN.

Note Catalyst 1900, Catalyst 2820, Catalyst 2900 XL, Catalyst 2940, Catalyst 2950, and Catalyst 3500 XL candidate and cluster member switches must be connected through their management VLAN to the cluster command switch and standby cluster command switches. For complete information about these switches in a switch-cluster environment, see the software configuration guide for that specific switch.

This requirement does not apply if you have a Catalyst 2960, Catalyst 2970, Catalyst 3550, Catalyst 3560, Catalyst 3560-E, Catalyst 3750, or Catalyst 3750-E cluster command switch. Candidate and cluster member switches can connect through any VLAN in common with the cluster command switch.

Planning a Switch Cluster

Anticipating conflicts and compatibility issues is a high priority when you manage several switches through a cluster. This section describes these guidelines, requirements, and caveats that you should understand before you create the cluster:

•Automatic Discovery of Cluster Candidates and Members, page 6-5

•HSRP and Standby Cluster Command Switches, page 6-11

•IP Addresses, page 6-14

•Hostnames, page 6-14

•Passwords, page 6-15

•SNMP Community Strings, page 6-15

•Switch Clusters and Switch Stacks, page 6-16

•TACACS+ and RADIUS, page 6-17

•LRE Profiles, page 6-17

See the release notes for the 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 for the required software versions and browser and Java plug-in configurations.

Catalyst 3750-E and 3560-E Switch Software Configuration Guide

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