switch in transparent mode

[sarahr202]

hi every body!

I find conflicting material about switch in transparent mode.

one cisco documents says:

Switch in vtp transparent mode saves vlan information in vlan.dat on flash and nvram.Upon reboot, if information in vlan.dat differs from that of nvram,switch use vlan.dat"

The other cisco press book says:

"When configured in vtp transparent mode, switch saves global configuration mode vlan configuration in switch configuration file. When the switch boots up, vlan database file is cleared,the vlan configuration stored in the switch configuration file is read which then populates the vlan database"

which one is correct?

thanks a lot!

[royalblues]

VTP server/client mode switches do not save the entire VTP/VLAN configuration to the startup config file in the NVRAM when you issue the copy running-config startup-config command on these systems. It saves the configuration in the vlan.dat file. This does not apply to systems that run as VTP transparent. VTP transparent systems save the entire VTP/VLAN configuration to the startup config file in NVRAM when you issue the copy running-config startup-config command. For example, if you delete vlan.dat file after the configuration of the VTP in server or client mode and reload the switch, it resets the VTP configuration to default settings. However, if you configure VTP in transparent mode, delete the vlan.dat and reload the switch. This retains the VTP configuration.

Have a look here

http://www.cisco.com/en/US/tech/tk389/tk689/technologies_tech_note09186a0080890613.shtml#topic2

HTH

Narayan

[sarahr202]

thanks for your reply. I think we don't need to use command copy running-config startup-config to save the configuration in vlan.dat.

When we create vlans or switch learns vlans via vtp, it stores them in vlan.dat. saving vlan information in vlan.dat does not require one to use copy running-config startup-config.

Correct me if I am wrong.

thanks a lot!

From your post, I get the impression that a switch in transparent mode only saves vtp and vlan database in nvram if we use the command copy running-config-startup-config.

Is it correct?

[glen.grant · Accepted solution]

When running client/server the info is not saved in running config , it is in the vlan.dat file.

When the switch is in transparent mode and you create vlans it is in the running config and will show up in the running config , to save the config and vlans info a "write mem" or "copy run start" command is needed to save the vlan information to the starup config .