DescriptionVTP Mode
VTPtransparent switches do notparticipate in VTP.A VTP transparent switch does not
advertiseits VLAN configuration and does not synchronizeits VLAN configuration based
onreceived advertisements. However, in VTP version 2 or version 3, transparent switches
doforward VTPadvertisements that theyreceive from otherswitches through theirtrunk
interfaces.You can create, modify,and delete VLANs on a switch in VTP transparent mode.
InVTP versions 1 and 2, the switch must be in VTP transparent mode when you create
extended-rangeVLANs. VTP version3 alsosupports creating extended-range VLANs in
clientor server mode.
InVTP versions 1 and 2, the switch must be in VTP transparent mode when you create
privateVLANs and when they are configured, you should not changethe VTP mode from
transparentto client or server mode. VTP version 3 also supports private VLANs in client
andserver modes. When private VLANs are configured, do not change the VTP mode from
transparentto client or servermode.
Whenthe switch is in VTP transparent mode, the VTP and VLAN configurations are saved
inNVRAM, but they are not advertised to other switches. In this mode, VTP mode and
domainname are saved in the switch running configuration, and you can save this information
inthe switch startup configuration file by using the copy running-config startup-config
privilegedEXEC command.
Ina switchstack, the running configuration and the saved configuration are the same for
allswitches in astack.
VTP
transparent
Aswitch in VTP off mode functions in the same manner as a VTP transparent switch, except
thatit doesnot forwardVTP advertisementson trunks.
VTPoff
Related Topics
ConfiguringVTP Mode, on page24
Example:Configuring the Switchas a VTPServer, on page 35
VTP Advertisements
Eachswitch in the VTP domainsends periodic global configuration advertisements from each trunk port to
areserved multicast address. Neighboring switches receive these advertisements and update their VTP and
VLANconfigurations as necessary.
Becausetrunk ports send and receive VTP advertisements, you must ensure that at least one trunk port is
configuredon the switch stack and that this trunk port is connected to the trunk port of another switch.
Otherwise,the switch cannotreceive any VTP advertisements.
VTPadvertisements distribute this global domain information:
VTPdomain name
VTPconfiguration revision number
Updateidentity and updatetimestamp
MD5digest VLANconfiguration, including maximum transmission unit (MTU)size for eachVLAN
Catalyst 2960-XR Switch VLAN Configuration Guide, Cisco IOS Release 15.0(2)EX1
16 OL-29440-01
Configuring VTP
VTP Advertisements