IBM 12.1(22)EA6 Manual Do Utilizador
13-5
Cisco Systems Intelligent Gigabit Ethernet Switch Modules for the IBM BladeCenter, Software Configuration Guide
24R9746
Chapter 13 Configuring VTP
Understanding VTP
VTP pruning blocks unneeded flooded traffic to VLANs on trunk ports that are included in the
pruning-eligible list. Only VLANs included in the pruning-eligible list can be pruned. By default,
VLANs 2 through 1001 are pruning eligible switch trunk ports. If the VLANs are configured as
pruning-ineligible, the flooding continues. VTP pruning is supported with VTP version 1 and version 2.
pruning-eligible list. Only VLANs included in the pruning-eligible list can be pruned. By default,
VLANs 2 through 1001 are pruning eligible switch trunk ports. If the VLANs are configured as
pruning-ineligible, the flooding continues. VTP pruning is supported with VTP version 1 and version 2.
shows a switched network without VTP pruning enabled. Port 1 on Switch A and Port 2 on
Switch D are assigned to the Red VLAN. If a broadcast is sent from the host connected to Switch A,
Switch A floods the broadcast and every switch in the network receives it, even though Switches C, E,
and F have no ports in the Red VLAN.
Switch A floods the broadcast and every switch in the network receives it, even though Switches C, E,
and F have no ports in the Red VLAN.
Figure 13-1
Flooding Traffic without VTP Pruning
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).
shown (Port 5 on Switch B and Port 4 on Switch D).
Figure 13-2
Optimized Flooded Traffic with VTP Pruning
Switch D
Switch E
Switch C
Switch F
Switch A
Switch B
Port 1
Port 2
Red
VLAN
89240
Switch D
Switch E
Switch C
Switch F
Switch A
Switch B
Port 1
Port 2
Red
VLAN
89241
Port
4
4
Flooded traffic
is pruned.
is pruned.
Port
5
5
Flooded traffic
is pruned.
is pruned.