Just want tinbe 100% sure..if I Chang my switch configurations to vtp mode off will they keep their current clans? Have only 4 switches and would rather manually manage vlan changes. They are all currently set to client mode.
1. You should be backing up your switch configs on a regular basis.
2. You should have a document stored offline which lists ALL your VLAN ID's, their corresponding names and Routable IP addresses.
3. You should be using security features like BPDUGuard and setting all host ports to be Access only to prevent rogue Cisco switches from being plugged in and Trunks forming.
If for some reason somebody was able to plug a Cisco switch into your network and it had the same Revision Number, VTP Domain and Password......and the port was able to form a trunk then there is potential for it to overwrite your Vlan database throughout your VTP domain.
These days, this is highly unlikely if you take the correct precautions as mentioned above. VTP updates are only sent through Trunk ports so all switchports should be 'Switchport Mode Access' unless that have been statically set to be a Trunk port as required.