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Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
OL-13270-01
Chapter12 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 V LANs. 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)” sec tion on page 13-12. 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 t he switc h 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 ma ximum n umb er 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 nu mb er of sp an ning- tre e instan ce s,
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 18, “Configuring MSTP.”
•Each routed port on the switch creates an internal VLAN for its use. These internal VLANs use
extended-range VLAN numbers, and the internal V LAN I D c an not be us ed for an ext end ed -ran ge
VLAN. If you try to create an extended-range VLAN with a VLAN ID that is already allocated as
an internal VLAN, an error message is generated, and the command is rejected.
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Because internal VLAN IDs are in the lower part of the extended range, we recom mend that you
create extended-range VLANs beginning from the highest nu mb er (4 094 ) and m oving to t he
lowest (1006) to reduce the possibility of using an internal VLAN ID.
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Before configuring extended-range VLANs, enter the show vlan internal usage privileged
EXEC command to see which VLANs have been allocated as internal VLANs.
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If necessary, you can shut down the routed port assigned to the internal VLAN, which frees up
the internal VLAN, and then create the extended-range VLAN and re-enable the port, which
then uses another VLAN as its internal VLAN. See the “Creating an Extended-Range VLAN
with an Internal VLAN ID” section on page12-15.
•Although the switch or switch stack supports a total of 1005 (normal-range and extended-range)
VLANs, the number of routed ports, SVIs, and other configured featur es affects the use of the switch
hardware. If you try to create an extended-range VLAN and t here are not enough hardware resources
available, an error message is generated, and the extended-range VLAN is rejected.
•In a switch stack, the whole stack uses the same running configuration and saved configuration, and
extended-range VLAN information is shared across the stack.