Cisco WS-C6506 Software Manual page 119

Chapter 5 Configuring Ethernet VLAN Trunks
Switch_1> (enable) show spantree 1/2
Port
--------- ----
1/2
1/2
1/2
1/2
1/2
1/2
1/2
1/2
1/2
Switch_1> (enable)
Figure 5-4
Figure 5-4
1/1
Figure 5-4
fails, the other trunk link acts as an alternate forwarding path for the traffic previously traveling over the
failed link.
If Trunk 1 fails in the network that is shown in
traffic from all the VLANs, as shown as follows:
Switch_1> (enable) 04/21/1998,03:15:40:DISL-5:Port 1/1 has become non-trunk
Switch_1> (enable) show spantree 1/1
Port
--------- ----
1/1
OL-8978-04
Vlan Port-State
-------------
1 blocking
10 blocking
20 blocking
30 blocking
40 forwarding
50 forwarding
60 forwarding
1003 not-connected
1005 not-connected
shows the network after you configure VLAN traffic load sharing.
Parallel Trunk Configuration After Configuring VLAN-Traffic Load Sharing
Trunk 2
VLANs 10, 20, and 30: port-VLAN priority 32 (blocking)
VLANs 40, 50, and 60: port-VLAN priority 1 (forwarding)
Switch 1
1/2
Trunk 1
VLANs 10, 20, and 30: port-VLAN priority 1 (forwarding)
VLANs 40, 50, and 60: port-VLAN priority 32 (blocking)
shows that both trunks are used when the network is operating normally; if one trunk link
Vlan Port-State
-------------
1 not-connected
Cost Priority Fast-Start
----- -------- ----------
19 32 disabled
19 32 disabled
19 32 disabled
19 32 disabled
19 1 disabled
19 1 disabled
19 1 disabled
19 32 disabled
19 4 disabled
Switch 2
1/1
Figure 5-4, STP reconverges to use Trunk 2 to forward
Cost Priority Fast-Start
----- -------- ----------
19 32 disabled
Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
Example VLAN Trunk Configurations
Group-method
------------
1/2
Group-method
------------
5-27