Specifications

216 ExtremeWare XOS 11.0 Concepts Guide
Spanning Tree Protocol
• All other ports in the network are in the forwarding state.
Figure 24: Initial network configuration
The following steps describe how the network reconverges.
1 If the link between bridge A and bridge F goes down, bridge F detects the root port is down. At this
point, bridge F:
• Immediately disables that port from the STP.
• Performs a configuration update.
As shown in Figure 25, after the configuration update, bridge F:
• Considers itself the new root bridge.
• Sends a BPDU message on its designated port to bridge E.
Figure 25: Down link detected
Designated
port
Root
port
EX_055a
A
A , 0
B
A , 1
C
A , 2
F
A , 1
E
A , 2
D
A , 3
Blocked
port
EX_055b
B
A , 1
C
A , 2
E
A , 2
D
A , 3
BPDU
Down
link
A
A , 0
F
F , 0
Designated
port
Root
port