13-11
Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Chapter13 Configuring VLANs
Configuring Extended-Range VLANs
Configuring Extended-Range VLANs
With VTP version 1 and version 2, when the switch is in VTP transparent mode (VTP disabled), you can
create extended-range VLANs (in the range 1006 to 4094). VTP version supports extended-range
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.
Note Although the switch supports 4094 VLAN IDs, see the “Supported VLANs” section on page13-2 for
the actual number of VLANs supported.
These sections contain extended-range VLAN configuration information:
Default VLAN Configuration, page13-11
Extended-Range VLAN Configuration Guidelines, page13-11
Creating an Extended-Range VLAN, page 13-12
Creating an Extended-Range VLAN with an Internal VLAN ID, page13-13

Default VLAN Configuration

See Table13-2 on page 13-8 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
the “Configuring VTP Mode” section on page14-11. You should save this configuration to the
startup configuration so that the switch boots 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 maximum number of
spanning-tree instances are on the switch, spanning tree is disabled on any newly created VLANs.