Due to numerous issues that can occur if there are multiple VTP servers that can change the configuration in a domain, VPTv3 introduces the concept of Primary VTP Server, which is the only switch that can perform changes to the VLAN information (together with the transparent switches, but they are independent). All other VTP servers actually work like clients, the difference being that they can be promoted to a Primary Serer role. To make things safer, switches will only accept VTP changes from the primary server they know and will ignore changes if another primary server comes up, even if its updates have a higher revision number.