VTPpruning is disabled in the switched network. Port 1 on Switch A and Port 2 on Switch D are assigned to
theRed VLAN. If abroadcast is sent from the host connected to Switch A, Switch A floods the broadcast
andevery switch in the network receives it, even though Switches C, E, and F have no ports in the Red VLAN.
Figure 1: Flooding Traffic without VTP Pruning
VTPpruning is enabledin the switched network. The broadcast traffic from Switch A is not forwarded to
SwitchesC, E, and F because traffic for the Red VLAN has been pruned on the links shown (Port 5 on Switch
Band Port 4 on SwitchD).
Figure 2: Optimized Flooded Traffic VTP Pruning
EnablingVTP pruning on a VTP server enables pruning for the entire management domain. Making VLANs
pruning-eligibleor pruning-ineligible affects pruning eligibility for those VLANs on that trunk only (not on
allswitches in theVTP domain).
VTPpruning takes effect several seconds after you enable it. VTP pruning does not prune traffic from VLANs
thatare pruning-ineligible. VLAN 1 and VLANs 1002 to 1005 are always pruning-ineligible; traffic from
theseVLANs cannot be pruned. Extended-range VLANs (VLAN IDs higher than 1005) are also
pruning-ineligible.
Catalyst 2960-XR Switch VLAN Configuration Guide, Cisco IOS Release 15.0(2)EX1
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Configuring VTP
VTP Pruning