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Configuring VTP
Information About Configuring VTP
Figure 33 Flooding Traffic without VTP Pruning
Figure 34 on page 301 shows a switched network with VTP pruning enabled. The broadcast traffic from Switch A is not
forwarded to Switches C, E, and F because traffic for the Red VLAN has been pruned on the links shown (Port 5 on Switch
B and Port 4 on Switch D).
Figure 34 Optimized Flooded Traffic with VTP Pruning
With VTP versions 1 and 2, enabling VTP pruning on a VTP server enables pruning for the entire management domain.
Making VLANs pruning-eligible or pruning-ineligible affects pruning eligibility for those VLANs on that trunk only (not on
all switches in the VTP domain). In VTP version 3, you must manually enable pruning on each switch in the domain.
See Enabling VTP Pruning, page 305. VTP pruning takes effect several seconds after you enable it. VTP pruning does
not prune traffic from VLANs that are pruning-ineligible. VLAN 1 and VLANs 1002 to 1005 are always pruning-ineligible;
traffic from these VLANs cannot be pruned. Extended-range VLANs (VLAN IDs higher than 1005) are also
pruning-ineligible.
VTP 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:
Turn off VTP pruning in the entire network.
Switch D
Switch E
Switch CSwitch F Switch A
Switch B
Port 1
Port 2
Red
VLAN
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Switch D
Switch E
Switch CSwitch F Switch A
Switch B
Port 1
Port 2
Red
VLAN
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Port
4
Flooded traffic
is pruned.
Port
5
Flooded traffic
is pruned.