Cisco IE 4000, Software Configuration Manual

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99
Configuring Switch Clusters
How to Plan for Switch Clustering
The cluster command switch in Figure 12 on page 99 belongs to VLANs 9 and 16. When new cluster-capable switches
join the cluster:

One cluster-capable switch and its access port are assigned to VLAN 9.

The other cluster-capable switch and its access port are assigned to management VLAN 16.
Figure 12 Discovery of Newly Installed Switches
IP Addresses
You must assign IP information to a cluster command switch. You can assign more than one IP address to the cluster
command switch, and you can access the cluster through any of the command-switch IP addresses. If you configure a
cluster standby group, you must use the standby-group virtual IP address to manage the cluster from the active cluster
command switch. Using the virtual IP address ensures that you retain connectivity to the cluster if the active cluster
command switch fails and that a standby cluster command switch becomes the active cluster command switch.
If the active cluster command switch fails and the standby cluster command switch takes over, you must either use the
standby-group virtual IP address or any of the IP addresses available on the new active cluster command switch to
access the cluster.
You can assign an IP address to a cluster-capable switch, but it is not necessary. A cluster member switch is managed
and communicates with other cluster member switches through the command-switch IP address. If the cluster member
switch leaves the cluster and it does not have its own IP address, you must assign an IP address to manage it as a
standalone switch.
For more information about IP addresses, see Performing Switch Setup Configuration, page 59
Hostnames
You do not need to assign a hostname to either a cluster command switch or an eligible cluster member. However, a
hostname assigned to the cluster command switch can help to identify the switch cluster. The default hostname for the
switch is
Switch .
If a switch joins a cluster and it does not have a hostname, the cluster command switch appends a unique member
number to its own hostname and assigns it sequentially as each switch joins the cluster. The number means the order in
which the switch was added to the cluster. For example, a cluster command switch named
eng-cluster could name the
fifth cluster member eng-cluster-5 .
If a switch has a hostname, it retains that name when it joins a cluster and when it leaves the cluster.
Command device
New (out-of-box)
candidate device
AP
Device A Device B
VLAN 9
VLAN 9
VLAN 16
VLAN 16
New (out-of-box)
candidate device
AP
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