Chapter 6 Clustering Switche - Cisco 3750G - Catalyst Integrated Wireless LAN Controller Configuration Manual

Understanding Switch Clusters
In a switch cluster, 1 switch must be the cluster command switch and up to 15 other switches can be
cluster member switches. The total number of switches in a cluster cannot exceed 16 switches. The
cluster command switch is the single point of access used to configure, manage, and monitor the cluster
member switches. Cluster members can belong to only one cluster at a time.
A switch cluster is different from a switch stack. A switch stack is a set of Catalyst 3750 switches
Note
connected through their stack ports. For more information about how switch stacks differ from switch
clusters, see the
The benefits of clustering switches include:
• Management of Catalyst switches regardless of their interconnection media and their physical
locations. The switches can be in the same location, or they can be distributed across a Layer 2 or
Layer 3 (if your cluster is using a Catalyst 3550, Catalyst 3560, or Catalyst 3750 switch as a Layer 3
router between the Layer 2 switches in the cluster) network.
Cluster members are connected to the cluster command switch according to the connectivity
guidelines described in the
page
Catalyst 2820, Catalyst 2900 XL, Catalyst 2950, and Catalyst 3500 XL switches. For complete
information about these switches in a switch-cluster environment, refer to the software
configuration guide for that specific switch.
• Command-switch redundancy if a cluster command switch fails. One or more switches can be
designated as standby cluster command switches to avoid loss of contact with cluster members. A
cluster standby group is a group of standby cluster command switches.
Management of a variety of Catalyst switches through a single IP address. This conserves on IP
•
addresses, especially if you have a limited number of them. All communication with the switch
cluster is through the cluster command switch IP address.
Table 6-1
command switches and which ones can only be cluster member switches, and the required software
versions.
Table 6-1
Switch
Catalyst 3750
Catalyst 3560
Catalyst 3550
Catalyst 2970
Catalyst 2960
Catalyst 2955
Catalyst 2950
Catalyst 2950 LRE
Catalyst 2940
Catalyst 3500 XL
Catalyst 2900 XL (8-MB switches)
Catalyst 3750 Switch Software Configuration Guide
6-2
"Switch Clusters and Switch Stacks" section on page
"Automatic Discovery of Cluster Candidates and Members" section on
6-5. This section includes management VLAN considerations for the Catalyst 1900,
lists the Catalyst switches eligible for switch clustering, including which ones can be cluster
Switch Software and Cluster Capability
Cisco IOS Release
12.1(11)AX or later
12.1(19)EA1b or later
12.1(4)EA1 or later
12.1(11)AX or later
12.2(25)FX or later
12.1(12c)EA1 or later
12.0(5.2)WC(1) or later
12.1(11)JY or later
12.1(13)AY or later
12.0(5.1)XU or later
12.0(5.1)XU or later
Chapter 6 Clustering Switches
6-15.
Cluster Capability
Member or command switch
Member or command switch
Member or command switch
Member or command switch
Member or command switch
Member or command switch
Member or command switch
Member or command switch
Member or command switch
Member or command switch
Member or command switch
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