Common Problems with VTP Configuration

Updates not received as expected

- VTP domain and password must match.

Missing VLANs

- Configuration has been overwritten by another VTP device.

Too many VLANs

- Consider making VTP domain smaller.

Common Problems with VTP Configuration

The table describes some unexpected results that can occur after VTP configuration.

Problem

Possible Causes

Updates not received as expected

■ VTP domain name and password must match on a given switch to receive updates from a VTP server. The domain name is case sensitive.

■ VTP version must be compatible with other switches in the domain.

■ Ensure that there is at least one server in the domain.

■ Check that a trunk link exists to VTP server.

Missing VLANs

■ Upon initial configuration, the VTP server may have had a partial VLAN database, and it overwrote the existing, more complete, database on the existing switch.

■ VLANs were deleted individually at the VTP server, and those deletions will be propagated in the domain. (To avoid this, ensure that any switch becoming a VTP server has a complete VLAN list.)

■ Not all Cisco switches support the same extended-range VLANs (those numbered higher than 1005). This information is not learned or propagated through VTP, so it may vary in a switched network.

Too many VLANs

■ The VTP server has a VLAN list that is more complete than the list needed by other switches in the domain.

© 2006 Cisco Systems, Inc. Defining VLANs 2-97

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