Vlan Configuration Guidelines And Restrictions - Cisco 7604 Configuration Manual

VLAN Configuration Guidelines and Restrictions

Table 14-6 Token Ring (TrBRF) VLAN Defaults and Ranges (continued)
Parameter
MTU size
Bridge number
STP type
VLAN state
VLAN Configuration Guidelines and Restrictions
When creating and modifying VLANs in your network, follow these guidelines and restrictions:
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Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
14-8
Supervisor engine redundancy does not support nondefault VLAN data file names or locations. Do
not enter the vtp file file_name command on a router that has a redundant supervisor engine.
Before installing a redundant supervisor engine, enter the no vtp file command to return to the
default configuration.
RPR+ redundancy (see Chapter 8, "Configuring RPR and RPR+ Supervisor Engine
does not support a configuration entered in VLAN database mode. Use global configuration mode
with RPR+ redundancy.
You can configure extended-range VLANs only in global configuration mode. You cannot configure
extended-range VLANs in VLAN database mode. See the
on page 14-9.
Before you can create a VLAN, the Cisco 7600 series router must be in VTP server mode or VTP
transparent mode. For information on configuring VTP, see
The VLAN configuration is stored in the vlan.dat file, which is stored in nonvolatile memory. You
can cause inconsistency in the VLAN database if you manually delete the vlan.dat file. If you want
to modify the VLAN configuration or VTP, use the commands described in this guide and in the
Cisco IOS Master Command List, Release 12.2SX publication.
To do a complete backup of your configuration, include the vlan.dat file in the backup.
The Cisco IOS end command is not supported in VLAN database mode.
You cannot enter Ctrl-Z to exit VLAN database mode.
Cisco 7600 series routers do not support Token Ring or FDDI media. The router does not forward
FDDI, FDDI-Net, TrCRF, or TrBRF traffic, but it can propagate the VLAN configuration through
VTP.
When a Cisco 7600 series router is configured as a VTP server, you can configure FDDI and Token
Ring VLANs from the router.
You must configure a TrBRF before you configure the TrCRF (the parent TrBRF VLAN you specify
must exist).
In a Token Ring environment, the logical interfaces (the connection between the TrBRF and the
TrCRF) of the TrBRF are placed in a blocked state if either of these conditions exists:
The TrBRF is running the IBM STP, and the TrCRF is in SRT mode.
–
The TrBRF is running the IEEE STP, and the TrCRF is in SRB mode.
–
Default
VTPv1 1500; VTPv2 4472
1
ibm
active
Chapter 14 Configuring VLANs
Range
1500–18190
0–15
auto, ibm, ieee
active, suspend
Redundancy")
"VLAN Configuration Options" section
Chapter 13, "Configuring VTP."
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