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Cisco IE 2000 Switch Software Configuration Guide
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Chapter 17 Configuring VLANs
VLANs
If you are assigning a port on a cluster member switch to a VLAN, first use the rcommand privileged
EXEC command to log in to the cluster member switch.
Note If you assign an interface to a VLAN that does not exist, the new VLAN is created. (See the “Creating
or Modifying an Ethernet VLAN” section on page 17-17.)
Extended-Range VLANs
With VTP version 1 and version 2, when the switch is in VTP transparent mode (VTP disabled), you c an
create extended-range VLANs (in the range 1006 to 4096). VTP version supports extended-rang e
VLANs in server or transparent move. Extended-range VLANs enable service providers to extend their
infrastructure to a greater number of customers. The extended-range VLAN IDs are allowed for any
switchport commands that allow VLAN IDs.
With VTP version 1 or 2, extended-range VLAN configurations are not stored in the VLAN database,
but because VTP mode is transparent, they are stored in the switch running configuration file, and you
can save the configuration in the startup configuration file by using the copy running-config
startup-config privileged EXEC command. Extended-range VLANs created in VTP version 3 are stored
in the VLAN database.

Default VLAN Configuration

See Table 17-2 on page 17-7 for the default configuration for Ethernet VLANs. You can change only the
MTU size, private VLAN, and the remote SPAN configuration state on extended-range VLANs; all other
characteristics must remain at the default state.

Extended-Range VLAN Configuration Guidelines

Follow these guidelines when creating extended-range VLANs:
• VLAN IDs in the extended range are not saved in the VLAN database and are not recognized by
VTP unless the switch is running VTP version 3.
• You cannot include extended-range VLANs in the pruning eligible range.
• In VTP version 1 and 2, a switch must be in VTP transparent mode when you create extended-range
VLANs. If VTP mode is server or client, an error message is generated, and the extended-range
VLAN is rejected. VTP version 3 supports extended VLANs in server and transparent modes.
• For VTP version 1 or 2, you can set the VTP mode to transparent in global configuration mode. See
“Adding a VTP Client Switch to a VTP Domain” section on page 18-10. You should save this
configuration to the startup configuration so that the switch boot s up in VTP transparent mode.
Otherwise, you lose the extended-range VLAN configuration if the switch resets. If you create
extended-range VLANs in VTP version 3, you cannot convert to VTP version 1 or 2.
• STP is enabled by default on extended-range VLANs, but you can disable it by using the no
spanning-tree vlan vlan-id global configuration command. When the ma ximum number of
spanning-tree instances are on the switch, spanning tree is disabled on any newly created VLANs.
If the number of VLANs on the switch exceeds the maximum number of spanning-tree instances,
we recommend that you configure the IEEE 802.1s Multiple STP (MSTP) on your switch to map
multiple VLANs to a single spanning-tree instance. For more information about MSTP, see
Chapter 21, “Configuring MSTP.”