Load-Sharing Vlan Traffic Over Parallel Trunks Example - Cisco WS-C4003 - Catalyst 4000 Chassis Switch Software Configuration Manual

Chapter 11 Configuring VLAN Trunks on Fast Ethernet and Gigabit Ethernet Ports
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Switch_A> (enable)
Switch_B> (enable) show trunk
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Switch_B> (enable)

Load-Sharing VLAN Traffic over Parallel Trunks Example

Using spanning tree port-VLAN priorities, you can load-share VLAN traffic over parallel trunk ports so
that traffic from some VLANs travels over one trunk, while traffic from other VLANs travels over the
other trunk. This configuration allows traffic to be carried over both trunks simultaneously (instead of
keeping one trunk in blocking mode), which reduces the total traffic carried over each trunk while still
maintaining a fault-tolerant configuration.
Figure 11-2
ports on the supervisor engine.
78-12647-02
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1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
Vlans in spanning tree forwarding state and not pruned
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Mode Encapsulation
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auto dot1q
auto dot1q
auto dot1q
auto dot1q
Vlans allowed on trunk
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1-1005
1-1005
1-1005
1-1005
Vlans allowed and active in management domain
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1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
Vlans in spanning tree forwarding state and not pruned
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1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
1-5,10,20,50,152,200,300,400,500,521-524,570,850,917,999
shows a parallel trunk configuration between two switches, using the Fast Ethernet uplink
Software Configuration Guide—Catalyst 4000 Family, Catalyst 2948G, Catalyst 2980G, Releases 6.3 and 6.4
Status Native vlan
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trunking 1
trunking 1
trunking 1
trunking 1
Example VLAN Trunk Configurations
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