Cisco Gigabit Ethernet Switch Module for HP p-Class BladeSystem Software Configuration Guide

CHAPTER

9-1

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Configuring VLANs

This chapter describes how to configure normal-range VLANs (VLAN IDs 1 to 1005) and

extended-range VLANs (VLAN IDs 1006 to 4094) on the switch. It includes information about VLAN

membership modes, VLAN configuration modes, VLAN trunks, and dynamic VLAN assignment from

a VLAN Membership Policy Server (VMPS).

Note For complete syntax and usage information for the commands used in this chapter, see the command

reference for this release.

The chapter consists of these sections:

• Understanding VLANs, page 9-1

• Configuring Normal-Range VLANs, page 9-4

• Configuring Extended-Range VLANs, page 9-11

• Displaying VLANs, page 9-14

• Configuring VLAN Trunks, page 9-14

• Configuring VMPS, page 9-25

Understanding VLANs

A VLAN is a switched network that is logically segmented by function, project team, or application,

without regard to the physical locations of the users. VLANs have the same attributes as physical LANs,

but you can group end stations even if they are not physically located on the same LAN segment. Any

switch port can belong to a VLAN, and unicast, broadcast, and multicast packets are forwarded and

flooded only to end stations in the VLAN. Each VLAN is considered a logical network, and packets

destined for stations that do not belong to the VLAN must be forwarded through a router or a switch

supporting fallback bridging, as shown in Figure 9-1. Because a VLAN is considered a separate logical

network, it contains its own bridge Management Information Base (MIB) information and can support

its own implementation of spanning tree. See Chapter 12, “Configuring STP.”

Note Before you create VLANs, you must decide whether to use VLAN Trunking Protocol (VTP) to maintain

global VLAN configuration for your network. For more information on VTP, see Chapter 10,

“Configuring VTP.”