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Cisco MGX 8850 (PXM1E/PXM45), Cisco MGX 8950, Cisco MGX 8830, and Cisco MGX 8880 Configuration Guide
Release 5.0.10, OL-3845-01 Rev. B0, August 16, 2004
Chapter 9 Switch Operating Procedures
Managing Redundant APS Lines
Line failures are always detected at the receive end of the line. This is where a switchover occurs when
a failure is detected. Two different types of switchovers can occur, depending on whether the APS was
configured as unidirectional or bidirectional in the cnfapsln command:
•
When a failure occurs on a line configured for unidirectional switching, the switch changes lines at
the receive end only. A switchover is not necessary at the transmit end because the transmitting back
cards send signals on both lines in the 1 +1 APS configuration.
•
When a failure occurs on a line configured for bidirectional switching, a switchover occurs at both
ends of the line.
If the status of the standby line is good, a switchover from the failed active line to the standby is
automatic.
Enter the cnfapsln command to enable an automatic switchover back to the working line after it recovers
from a failure, as shown in the following example:
mgx8830a.1.PXM.a >
cnfapsln
-w 1.1.1 -rv 2
describes the configurable parameters for the cnfapsln command.
Table 9-4
cnfapsln Command Parameters
Parameter
Description
-w <working line>
Slot number, bay number, and line number of the active line to
configure, in the following format:
slot.bay.line
Example:
-w 1.1.1
-sf <signal fault ber>
A number between 3 and 5 indicating the Signal Fault Bit Error Rate
(BER), in powers of ten.
•
3 = 10
-3
•
4 = 10
-4
•
5 = 10
-5
Example:
-sf 3
-sd <SignalDegradeBER>
A power if 10 in the range 5–9 that indicates the Signal Degrade Bit
Error Rate (BER):
•
5 = 10
-5
•
6 = 10
-6
•
7 = 10-7
•
8 = 10
-8
•
9 = 10
-9
Example:
-sd 5
-wtr <Wait To Restore>
The number of minutes to wait after the failed working line has
recovered, before switching back to the working line. The range is
5–12.
Example:
-wtr 5
