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Catalyst 2950 Desktop Switch Software Configuration Guide
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Chapter 15 Configuring VTP Understanding VTP
Figure 15-1 Flooding Traffic without VTP Pruning
Figure 15-2 shows a swi tched network w ith V T P pruni ng ena ble d. The broa dcast tra ffic from Sw itch 1
is not for war ded to Switches 3, 5, and 6 because traffic for the Red VL AN has been pruned on the links
shown (Port 5 on Switch 2 and Port 4 on Switch 4).
Figure 15-2 Optimized Flooded Traffic with VTP Pruning
Enab ling V T P prun in g on a V TP ser ver e nabl es p run ing f or the ent ire ma nagem e nt d oma in. Mak ing
VLANs pruning-eligible or pruning-ineligible af fects pruning eligibility for those VLANs on that de vice
only (not on all switches in the VTP domain). See the Enablin g VTP Pruni ng sec tion on p ag e 15-14.
VTP pruning t akes effect several seconds af ter you enable it. VTP pruning do es not pru ne traffic from
VLANs t hat are pru ning- ine lig ible. VLA N 1 a nd VLAN s 100 2 to 10 05 are a lways pr uning -ine li gibl e;
traffic from these VLANs cannot be pruned. Extended-range VLANs (VLAN IDs higher than 1005) are
also pr unin g-ine li gibl e.
Switch 4
Switch 5
Switch 3Switch 6 Switch 1
Switch 2
Port 1
Port 2
Red
VLAN
45826
Switch 4
Switch 5
Switch 3Switch 6 Switch 1
Switch 2
Port 1
Port 2
Red
VLAN
45827
Port
4
Port
5
Flooded traffic
is pruned.
Flooded traffic
is pruned.