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Ethernet Card Software Feature and Configuration Guide, R7.2
January 2009
Chapter 21 Configuring RMON
Unwrap Synchronization
Figure 21-5 First Stage of Unwrapped Cisco proprietary RPR with Bidirectional Excessive CRC
Errors
Node E has not unwrapped POS port 1 after the first CRC-ALARM clear command. Since node D
continues to send PDI to node E, node E will raise the TPTFAIL alarm once the CRC-ALARM is cl eared.
At this point, the Cisco proprietary RPR is in a state similar to the unidirectional failure. The unwrap
completes after the user issues the second unwrap command, as illustrated by Figure 21-5.
User issues
unwrap command.
Node B
Node C