Siemens S223 - Manual (Page 266)

UMN:CLI User Manual
SURPASS hiD 6615 S223/S323 R1.5
266 A50010-Y3-C150-2-7619
Normal Node Normal Node
Normal Node RM Node
P
S
1. Secondary port of RM node is
changed as unblocking state
2. Send Link
Down Message
2. Send Link
Down Message
Fig. 8.36 Ring Protection
When a Link Failure is recovered, a temporary loop may occur. To rectify this condition,
ERP sends a “link up” message to the RM. The RM will logically block the protected
VLANs on its secondary port and generate a “RM link up” packet to make sure that all
transit nodes are properly reconfigured. This completes fault restoration and the ring is
back in normal state.
2. Nodes detecting Link Failure
send Link Down message
2. Nodes detecting Link Failure
send Link Down message
Normal Node Normal Node
1. Link Failure recover
blocks the port
recovered from Link
Failure
Normal Node RM Node
P
S
Fig. 8.37 Link Failure Recovery