Cisco Systems 3750E manual Using Snmp to Manage Switch Clusters, Snmp Management for a Cluster

Chapter 6 Clustering Switches

Using SNMP to Manage Switch Clusters

Using SNMP to Manage Switch Clusters

When you first power on the switch, SNMP is enabled if you enter the IP information by using the setup program and accept its proposed configuration. If you did not use the setup program to enter the IP information and SNMP was not enabled, you can enable it as described in the “Configuring SNMP” section on page 33-6. On Catalyst 1900 and Catalyst 2820 switches, SNMP is enabled by default.

When you create a cluster, the cluster command switch manages the exchange of messages between cluster member switches and an SNMP application. The cluster software on the cluster command switch appends the cluster member switch number (@esN, where N is the switch number) to the first configured read-write and read-only community strings on the cluster command switch and propagates them to the cluster member switch. The cluster command switch uses this community string to control the forwarding of gets, sets, and get-next messages between the SNMP management station and the cluster member switches.

Note When a cluster standby group is configured, the cluster command switch can change without your knowledge. Use the first read-write and read-only community strings to communicate with the cluster command switch if there is a cluster standby group configured for the cluster.

If the cluster member switch does not have an IP address, the cluster command switch redirects traps from the cluster member switch to the management station, as shown in Figure 6-8. If a cluster member switch has its own IP address and community strings, the cluster member switch can send traps directly to the management station, without going through the cluster command switch.

If a cluster member switch has its own IP address and community strings, they can be used in addition to the access provided by the cluster command switch. For more information about SNMP and community strings, see Chapter 33, “Configuring SNMP.”

Figure 6-8 SNMP Management for a Cluster

SNMP Manager Command switch

Trap 1, Trap 2, Trap 3

Trap

Member 1

Trap	Trap
	33020
Member 2	Member 3

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

OL-9775-02 6-19