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6-7
Catalyst 3550 Multilayer Switch Software Configuration Guide
78-11194-09
Chapter 6 Clustering Switches
Planning a Switch Cluster
Figure 6-2
Discovery through Non-CDP-Capable and Noncluster-Capable Devices
Discovery through Different VLANs
If the command switch is a Catalyst 3550 switch, the cluster can have member switches in different
VLANs. Catalyst 3550 member switches must be connected through at least one VLAN in common with
the command switch. The command switch in
has ports assigned to VLANs 9, 16, and 62 and
therefore discovers the switches in those VLANs. It does not discover the switch in VLAN 50. It also
does not discover the switch in VLAN 16 in the first column because the command switch has no VLAN
connectivity to it.
Catalyst 2900 XL member switches, Catalyst 2950 member switches running a release earlier than Cisco
IOS Release 12.1(9)EA1, and Catalyst 3500 XL member switches must be connected to the command
switch through their management VLAN. For information about discovery through management
VLANs, see the
“Discovery through the Same Management VLAN” section on page 6-8
and the
“Discovery through Different Management VLANs” section on page 6-9
. For more information about
VLANs, see
Chapter 12, “Configuring VLANs.”
Figure 6-3
Discovery through Different VLANs
Si
Command switch
Catalyst 5000 switch
(noncluster-capable)
Third-party hub
(non-CDP-capable)
Catalyst 3500 XL
candidate switch
Catalyst 3550
candidate switch
54981
Si
VLAN 62
VLAN 62
VLAN 16
VLAN trunk 9,16
Command switch
VLAN 50
VLAN trunk 9,16
VLAN trunk 4,16
54982