Specifications

5-8
Catalyst 2970 Switch Software Configuration Guide
78-15462-03
Chapter 5 Clustering Switches
Planning a Switch Cluster
Discovery Through Different Management VLANs
Catalyst 2970, Catalyst 3550, or Catalyst 3750 cluster command switches can discover and manage
cluster member switches in different VLANs and different management VLANs. As cluster member
switches, they must be connected through at least one VLAN in common with the cluster command
switch. They do not need to be connected to the cluster command switch through their management
VLAN. The default management VLAN is VLAN 1.
Note If the switch cluster has a Catalyst 3750 switch or switch stack, that switch or switch stack must be the
cluster command switch.
The cluster command switch and standby command switch in Figure 5-4 have ports assigned to
VLANs 9, 16, and 62. The management VLAN on the cluster command switch is VLAN 9. Each cluster
command switch discovers the switches in the different management VLANs except these:
• Switches 7 and 10 (switches in management VLAN 4) because they are not connected through a
common VLAN (meaning VLANs 62 and 9) with the cluster command switch
• Switch 9 because automatic discovery does not extend beyond a noncandidate device, which is
switch 7
Figure 5-4 Discovery Through Different Management VLANs with a Layer 3 Cluster Command
Switch
Si
SiSi
VLAN 62
VLAN trunk 4, 62
VLAN 62
VLAN 16
VLAN 9
VLAN 16
VLAN 9
Standby command
switch
Command
switch
VLAN 9
Switch 7
(management
VLAN 4)
Switch 9
(management
VLAN 62)
VLAN 4
86887
Switch 3
(management
VLAN 16)
Switch 4
(management
VLAN 16)
Switch 10
(management
VLAN 4)
Switch 8
(management
VLAN 9)
Switch 6
(management
VLAN 9)
Switch 5
(management
VLAN 62)