Managing Switches

Configuring Switch Features

Stack Management with VLANs

You can use stacks in a VLAN environment. Each switch in the stack (Commander and Members) uses only the default VLAN configured in that switch for stack links. In the Web browser interface, this is the VLAN labeled Default <VLAN ID>. All VLANs in the stack need to be interconnected through the default VLAN.

The VLAN ID for the default VLAN must be the same for all switches in the stack. The default VLAN name can differ among switches in the stack. For example, if the VLAN ID (VID) for the default VLAN in Switch A is “1” and the default VID for Commander Switch B is “5”, then Switch A can't be a Candidate or a Member of Commander Switch B's stack, even though you may have connectivity to Switch A from Commander Switch B through other tagged VLANs.

Benefits of Stack Management

Stacking benefits include:

■Reducing the number of IP addresses required for managing your switches

■Increasing the scalability of your network to handle more traffic when used with switch meshing

■Simplifying network management for small groups

See the online help for more information about stack management.

VLAN Configuration

VLANs are a method for segmenting a network into related groups, improving the efficiency of traffic flow and limiting the propagation of multicast and broadcast messages. Traffic between VLANs is blocked unless the VLANs are connected by a router, increasing security.

A VLAN is a group of ports designated by the switch as belonging to the same broadcast domain. That is, all ports carrying traffic for a particular subnet address would belong to the same VLAN. Using a VLAN, you can group users by logical function instead of physical location. This helps to control bandwidth usage by allowing you to group high-bandwidth users on low-traffic segments and to organize users from different LAN segments according to their need for common resources. Beginning with release C.06.01 of the switch software (operating system, or “OS”) you can use the switch's console interface to configure up to 30 port-based, IEEE 802.1Q-compliant VLANs. (Earlier releases of the OS allow up to eight port-based, IEEE 802.1Q-compliant VLANs.) This enables you to use the same port for two or more VLANs and still allows interoperation with older switches that require a separate port for each VLAN.

The benefits of VLANs include:

■Grouping users into logical networks for increased performance

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