The VLAN database of the new switch will overwrite the VLAN databases of the production switches because it is operating in server mode and has a higher VLAN configuration revision number. The VLAN Trunking Protocol (VTP) is used to synchronize VLANs between different switches. The VTP configuration revision number is used to determine which VTP switch has the most current version of the VLAN database, and is incremented whenever a VLAN change is made on a VTP server switch. The show vtp status command is used to view the configuration revision number, as shown in this sample output:
Switch# show vtp status VTP Version : 2 Configuration Revision : 62 Maximum VLANs supported locally : 1005 Number of existing VLANs : 24 VTP Operating Mode : Server VTP Domain Name : Corporate VTP Pruning Mode : Enabled VTP V2 Mode : Disabled VTP Traps Generation : Disabled MD5 digest : 0x45 0x52 0xB6 0xFD 0x63 0xC8 0x49 0x80
This switch has a configuration revision number of 62, which will be compared to other switches in the same VTP domain. If the production switches have a lower configuration revision number than the new switch, their VLAN databases will be replaced with the VLAN database of the new switch. This could mean that VLANs that formerly existed on those production switches may be deleted. Any switch ports that had been assigned to VLANs that become deleted will be disabled, possibly resulting in catastrophic network failure. All VTP switches in the same VTP domain should have a domain password defined, which will protect against a rogue switch being added to the network and causing VLAN database corruption.

The new switch does not have a lower configuration revision number, since this would cause the new switch to have its VLAN database replaced with the existing production VLANs. This would not cause the problem described in the scenario.

The new switch is not operating in transparent VTP mode because a switch operating in transparent VTP mode will never synchronize its VLAN database with other switches.