9-12
Catalyst 2360 Switch Software Configuration Guide
OL-19808-01
Chapter 9 Configuring VLANs
Configuring Extended-Range VLANs
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 database 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 database
configuration mode. See the
“Disabling VTP (VTP Transparent Mode)” section on page 10-12
. 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.
•
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.
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 12, “Configuring MSTP.”
•
Although the switch supports a total of 128 (normal-range and extended-range) VLANs, the number
of SVIs and other configured features affects the use of the switch hardware. If you try to create an
extended-range VLAN and there are not enough hardware resources available, an error message is
generated, and the extended-range VLAN is rejected.
Creating an Extended-Range VLAN
You create an extended-range VLAN in global configuration mode by entering the
vlan
global
configuration command with a VLAN ID from 1006 to 4094. This command accesses the config-vlan
mode. The extended-range VLAN has the default Ethernet VLAN characteristics (see
) and the
MTU size and RSPAN configuration are the only parameters you can change. See the description of the
vlan
global configuration command in the command reference for the default settings of all parameters.
If you enter an extended-range VLAN ID when the switch is not in VTP transparent mode, an error
message is generated when you exit from config-vlan mode, and the extended-range VLAN is not
created.
Extended-range VLANs are not saved in the VLAN database; they are saved in the switch running
configuration file. You can save the extended-range VLAN configuration in the switch startup
configuration file by using the
copy running-config startup-config
privileged EXEC command.
Note
Before you create an extended-range VLAN, you can verify that the VLAN ID is not used internally by
entering the
show vlan internal usage
privileged EXEC command.