Pruning increases available
bandwidth by restricting flooded traffic to those trunk links that the traffic
must use to access the destination devices. You can only enable VTP pruning on
switch in VTP server mode.
With VTP versions 1 and 2,
when you enable pruning on the VTP server, it is enabled for the entire VTP
domain. In VTP version 3, you must manually enable pruning on each
switch in the domain.
Only VLANs included in the
pruning-eligible list can be pruned. By default, VLANs 2 through 1001 are
pruning-eligible on trunk ports. Reserved VLANs and extended-range VLANs cannot
pruning is not designed to function in VTP transparent mode. If one or more
switches in the network are in VTP transparent
mode, you should do one of these actions:
To configure VTP pruning on
an interface, use the
switchport trunk pruning vlan interface
configuration command. VTP pruning operates when an interface is trunking. You
can set VLAN pruning-eligibility, whether or not VTP pruning is enabled for the
VTP domain, whether or not any given VLAN exists, and whether or not the
interface is currently trunking.