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Catalyst 2940 Switch Software Configuration Guide
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Chapter5 Clustering Switches
Planning a Switch Cluster
For more information about CMS access modes, see the “Privilege Levels” section on page3-6.
Note • If your cluster has these member switches running earlier software releases and if you have
read-only access to these member switches, some configuration windows for thos e switches display
incomplete information:
–
Catalyst 2900 XL or Catalyst 3500 XL member switches ru nni ng Ci sco IOS
Release 12.0(5)WC2 or earlier
–
Catalyst 2950 member switches running Cisco IOS Release 12.0(5)WC2 or e arl ier
–
Catalyst 3550 member switches running Cisco IOS Release 12.1(6)EA1 or earlier
For more information about this limitation, refer to the release notes.
•These switches do not support read-only mode on CMS:
–
Catalyst 1900 and Catalyst 2820
–
Catalyst 2900 XL switches with 4-MB CPU DRAM
In read-only mode, these switches appear as unavailable devices and ca nno t be con figure d fro m
CMS.
Management VLAN
Communication with the switch management interfaces is through the command-switch IP address. The
IP address is associated with the management VLAN, which by default is VLAN 1. To manage switches
in a cluster, the command switch, member switches, and candidat e switches must be connected through
ports assigned to the command-switch management VLAN.
If you add a new, out-of-box switch to a cluster and the cluster is using a manageme nt VLAN other than
the default VLAN 1, the command switch automatically senses that the new switch has a different
management VLAN and has not been configured. The command switch issues commands to change the
management VLAN of the new switch to the one the cluster is using. This automatic VLAN change only
occurs for new, out-of-box switches that do not have a config.text file and that have no changes to the
running configuration. For more information, see the “Discovery of Newly Installed Switches” section
on page 5-7.
You can change the management VLAN of a member switch (not th e co mm an d s wi tc h). However, the
command switch will not be able to communicate with it. In this case, you will need to manage the switch
as a standalone switch.
You can globally change the management V LAN for the cluster as lo ng as each member swit ch has either
a trunk connection or a connection to the new command-switch management VLAN. From the command
switch, use the cluster management vlan global configuration command to change the cluster
management VLAN to a different management VLAN.
Caution You can change the management VLAN through a console connection without interrupting the console
connection. However, changing the management VLAN ends your CMS session. Restart your CMS
session by entering the new IP address in the browser Location field (Netscape Communicator) or
Address field (Microsoft Internet Explorer), as described in the release notes.
For more information about changing the management VLAN, see the “M anagement VLAN” section on
page 5-14.