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Catalyst 2950 Desktop Switch Software Configuration Guide
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Chapter 13 Configuring VLANs
Configuring Extended-Range VLANs
Configuring Extended-Range VLANs
When the switch is in VTP transparent mode (VTP disabled) and the EI is installed), you can create
extended-range VLANs (in the range 1006 to 4094). 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. You always use config-vlan mode
(accessed by entering the vlan vlan-id global configuration command) to configure extended-range
VLANs. The extended range is not supported in VLAN configuration mode (accessed by entering the
vlan database privileged EXEC command).
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.
Note Although the switch supports 4094 VLAN IDs when the EI is installed, see the “Supported VLANs”
section on page 13-2 for the actual number of VLANs supported.
This section includes this information about extended-range VLANs:
• Default VLAN Configuration, page 13-12
• Extended-Range VLAN Configuration Guidelines, page 13-12
• Creating an Extended-Range VLAN, page 13-13
• Displaying VLANs, page 13-14
Default VLAN Configuration
See Table 13-2 on page 13-8 for the default configuration for Ethernet VLANs. You can change only the
MTU size 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:
• To add an extended-range VLAN, you must use the vlan vlan-id global configuration command and
access config-vlan mode. You cannot add extended-range VLANs in VLAN configuration mode
(accessed by entering the vlan database privileged EXEC command).
• VLAN IDs in the extended range are not saved in the VLAN database and are not recognized by
VTP.
• You cannot include extended-range VLANs in the pruning eligible range.
• The 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.
• You can set the VTP mode to transparent in global configuration mode or in VLAN configuration
mode. See the “Disabling VTP (VTP Transparent Mode)” section on page 14-12. You should save
this configuration to the startup configuration so that the switch will boot up in VTP transparent
mode. Otherwise, you will lose extended-range VLAN configuration if the switch resets.
• VLANs in the extended range are not supported by VQP. They cannot be configured by VMPS.