Cisco BPX 8650, Installation And Configuration Manual

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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
Chapter 25 Configuring SONET Automatic Protection System
APS 1+1 (Card and Line Redundancy)
Note
In the APS 1+1 configuration, if the protection line is active and the last user request is “clear,” a
switchdred causes the working line to be active if there is no line condition on working line. When
APS 1+1 comes up, it comes up on the working line if the working line is clear. When a switchcdred
is issued, the active card also comes up on the working line if the working line is clear and there is
no user request.
In the case where the working line is in alarm or there is a user request to switch to
the protection line ( switchapsln ), the card will first come up on the working line. Then the card will
detect the alarm or the user request and switch to the protection line.
Notes on switchcdred
Note
In the APS 1+1 configuration, if the last user request was a W –> P switch, then dsplog will log a W
–> P switching event when a switchcdred is issued. On a switchcdred , the newly active card comes
up on working line first. Then it responds to a user request to switch from working to protection by
switching to the protection line and sending an event notification to that effect. The event
notification can be seen in the event log by using the dsplog command.
Note
It may be necessary to perform a switchcdred (switchyred) command after performing a service
switch with the switchapsln command so that the back card that the service switch selects has its
associated front card active.
Notes on switchapsln
With APS 1+1, when repetitive switchapsln commands are issued, up to two in a row can be executed
sequentially, when alternating between options 3 and 4 (forced switch), or 5 and 6 (manual switch), but
no more. Attempts to execute a third
switchapsnln will not succeed, and the following error message is
displayed:
“Cannot request manual W->P when manual P->W switch in progress”
If you wish to perform repetitive switchapsln commands, you should issue a clear switch between each
W-P, P-W pair of commands, for example:
switchapsln 2.1 1
Configuring APS 1+1
To configure APS 1+1 redundancy, use the following procedure:
Step 1 Verify that appropriate front and back cards are installed along with APS two-card daughterboard.
Step 2
Ensure that lines are connected, for example on port 1 of BXM card in slot 2 and port 1 of BXM card in
slot 3.
Step 3 Execute these commands and verify chan half= no, and standard= GR-253 (default)
cnfcdaps 2.1 N 1
cnfcdaps 3.1 N 1