IBM 12.1(22)EA6 User Manual
12-5
Cisco Systems Intelligent Gigabit Ethernet Switch Modules for the IBM BladeCenter, Software Configuration Guide
24R9746
Chapter 12 Configuring VLANs
Configuring Normal-Range VLANs
This section includes information about these topics about normal-range VLANs:
•
•
•
•
•
•
•
•
Token Ring VLANs
Although the switch does not support Token Ring connections, a remote device such as a Catalyst 5000
series switch with Token Ring connections could be managed from one of the supported switches.
Switches running VTP version 2 advertise information about these Token Ring VLANs:
series switch with Token Ring connections could be managed from one of the supported switches.
Switches running VTP version 2 advertise information about these Token Ring VLANs:
•
Token Ring TrBRF VLANs
•
Token Ring TrCRF VLANs
For more information on configuring Token Ring VLANs, see the Catalyst 5000 Series Software
Configuration Guide.
Configuration Guide.
Normal-Range VLAN Configuration Guidelines
Follow these guidelines when creating and modifying normal-range VLANs in your network:
•
Normal-range VLANs are identified with a number between 1 and 1001. VLAN numbers 1002
through 1005 are reserved for Token Ring and FDDI VLANs.
through 1005 are reserved for Token Ring and FDDI VLANs.
•
VLAN configuration for VLANs 1 to 1005 are always saved in the VLAN database. If VTP mode
is transparent, VTP and VLAN configuration are also saved in the switch running configuration file.
is transparent, VTP and VLAN configuration are also saved in the switch running configuration file.
•
The switch also supports VLAN IDs 1006 through 4094 in VTP transparent mode (VTP disabled).
These are extended-range VLANs, and configuration options are limited. Extended-range VLANs
are not saved in the VLAN database. See the
These are extended-range VLANs, and configuration options are limited. Extended-range VLANs
are not saved in the VLAN database. See the
•
Before you can create a VLAN, the switch must be in VTP server mode or VTP transparent mode.
If the switch is a VTP server, you must define a VTP domain, or VTP will not function.
If the switch is a VTP server, you must define a VTP domain, or VTP will not function.
•
The switch does not support Token Ring or FDDI media. The switch does not forward FDDI,
FDDI-Net, TrCRF, or TrBRF traffic, but it does propagate the VLAN configuration through VTP.
FDDI-Net, TrCRF, or TrBRF traffic, but it does propagate the VLAN configuration through VTP.
•
The switch supports 64 spanning-tree instances. If a switch has more active VLANs than supported
spanning-tree instances, spanning tree can be enabled on 64 VLANs and is disabled on the
remaining VLANs. If you have already used all available spanning-tree instances on a switch,
adding another VLAN anywhere in the VTP domain creates a VLAN on that switch that is not
running spanning tree. If you have the default allowed list on the trunk ports of that switch (which
is to allow all VLANs), the new VLAN is carried on all trunk ports. Depending on the topology of
the network, this could create a loop in the new VLAN that would not be broken, particularly if there
spanning-tree instances, spanning tree can be enabled on 64 VLANs and is disabled on the
remaining VLANs. If you have already used all available spanning-tree instances on a switch,
adding another VLAN anywhere in the VTP domain creates a VLAN on that switch that is not
running spanning tree. If you have the default allowed list on the trunk ports of that switch (which
is to allow all VLANs), the new VLAN is carried on all trunk ports. Depending on the topology of
the network, this could create a loop in the new VLAN that would not be broken, particularly if there