Vtp Modes; Vtp Per Interface; Vtp Pruning - Cisco Nexus 7000 Series Configuration Manual

Configuring VTP

VTP Modes

Beginning with Release 5.1(1), VTP is supported in these modes:
• Transparent—Allows you to relay all VTP protocol packets that it receives on a trunk port to all other
• Server— Allows you to create, remove, and modify VLANs over the entire network. You can set other
• Client—VTP clients behave the same way as VTP servers, but you cannot create, change, or delete
• Off— Behaves similarly to the transparent mode but does not forward any VTP packets. The off mode
Beginning with Cisco NX-OS Release 6.1(1), if VTP is in transparent or in off mode, you can configure
VLAN long names of up to 128 characters. If VTP is in client or server mode, you cannot enable VLAN
long-names. For more details, see the

VTP Per Interface

VTP allows you to enable or disable the VTP protocol on a per-port basis to control the VTP traffic. When a
trunk is connected to a switch or end device, it drops incoming VTP packets and prevents VTP advertisements
on this particular trunk. By default, VTP is enabled on all the switch ports.

VTP Pruning

The VLAN architecture requires all flooded traffic for a VLAN to be sent across a trunk port even if it leads
to switches that have no devices that are active in the VLAN. This method leads to wasted network bandwidth.
VTP pruning optimizes the usage of network bandwidth by restricting the flooded traffic to only those trunk
ports that can reach all the active network devices. When this protocol is in use, a trunk port does not receive
the flooded traffic that is meant for a certain VLAN unless an appropriate join message is received.
A join message is defined as a new message type in addition to the ones already supported by version 1 of
VTP. A VTP implementation indicates that it supports this extension by appending a special TLV at the end
of the summary advertisement messages that it generates. In VTP transparent mode, VTP relays all VTP
packets, and pruning requires that the switch processes TLVs in the VTP summary packets. You cannot use
pruning in VTP transparent mode.
trunk ports. When you create or modify a VLAN that is in VTP transparent mode, those VLAN changes
affect only the local device. A VTP transparent network device does not advertise its VLAN configuration
and does not synchronize its VLAN configuration based on received advertisements. You cannot configure
VLANs 1002 to 1005 in VTP client/server mode because these VLANs are reserved for Token Ring.
configuration options like the VTP version and also turn on or off VTP pruning for the entire VTP
domain. VTP servers advertise their VLAN configuration to other switches in the same VTP domain
and synchronize their VLAN configuration with other switches based on messages received over trunk
links. Beginning with Release 5.1(1), the server mode is the default mode. The VLAN information is
stored on the bootflash and is not erased after a reboot.
VLANs on a VTP client.
allows you to monitor VLANs by using the CISCO-VTP-MIB without having to run VTP. On Cisco
Nexus 7000 Series devices, because VTP is a conditional service, its MIB is loaded only when the
corresponding feature is enabled. The CISCO-VTP-MIB does not follow this convention. It is loaded
by the VLAN manager and will always return the correct values whether the VTP process is enabled or
disabled.
Cisco Nexus 7000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.x
Configuring VLANs chapter.
VTP Modes
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