IBM BladeCenter Installation And User Manual page 157

A
VLAN 2 VLAN 2
Blocked
VLAN 1 VLAN 1
C
VLAN 1 VLAN 1
In this example, the VLAN definitions are extended to switches A and B. This gives
only a single blocked port per VLAN and enables the removal of all redundant links
by removing switch A or B from the network.
Appendix D. Understanding and troubleshooting the Spanning Tree Protocol
Trunk
VLAN 1 VLAN 1
Blocked
D
VLAN 2 VLAN 2
B
VLAN 2 VLAN 2
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