Small question about VTP

A very small question about VTP as I am covering this topic and currently cant lab out the scenario. Lets say for example you have 2 switches in a VTP domain one is a server and one is a client. The client has a number of ports assigned as access ports to vlan 100 which was acquired via a VTP advertisement from the server. If the power cuts out and the client boots before the server, will the access ports revert back to VLAN 1 or retain the VLAN 100 configuration?

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kalebksp

It will retain the configuration. The only difference between a client and server is that from a management perspective you can't make changes on a client. A client with a higher database revision can even overwrite the database on a server.

kalebksp

By the way, if a switch were to lose a VLAN due to removal via VTP the ports assigned to that would be disabled, not placed into VLAN 1.

dredlord

Thank you for the prompt reply

MickQ

VLAN config is stored in a file in flash called the vlan.dat file.
It's filepath in the ios is flash:vlan.dat

In the case of a power loss or reboot, the running config is lost. The startup config becomes the running config. This gives the configuration of the device, but the vlan information is then read from the vlan.dat.

As kalebksp said, a client mode device can replace a server mode device's vlan.dat info if the revision number of the client is higher than the server's, and the VTP domain also has to match on both devices.

xXErebuS

MickQ wrote: »

VLAN config is stored in a file in flash called the vlan.dat file.
It's filepath in the ios is flash:vlan.dat

In the case of a power loss or reboot, the running config is lost. The startup config becomes the running config. This gives the configuration of the device, but the vlan information is then read from the vlan.dat.

As kalebksp said, a client mode device can replace a server mode device's vlan.dat info if the revision number of the client is higher than the server's, and the VTP domain also has to match on both devices.

Exactly... I will NEVER use VTP for this reason...

MickQ

Indeed. It's also the recommended way to go with VTP, at the CCDP level; transparent or off (v3).

For CCNA/P, DA, it's recommended to use VTP - at least that is according to the OCG stuff I read.