Mocomtech CRS-300 - Manual (Page 167)

CRS-300 1:10 Redundancy Switch Revision 16
Modem, RMI/TMI, and Switch Configuration MN/CRS300.IOM
5–23
To enable Auto mode:
Step Procedure
1 Go to the CONFIG Æ AUTO menu and turn on AUTO mode.
2 Verify that the Stored Event LED stops blinking.
5.5.3.4 Set Holdoff Period
A holdoff period prevents unwarranted backups due to an intermittent fault. When in Auto mode,
additional delays may be introduced to the backup procedure by setting the number of seconds for
"holdoff" before a faulted Traffic Modem cedes operation to the Redundant Modem (backup), or
operation is returned from the Redundant Modem back to the Traffic Modem (restore).
The process is further explained:
If a fault occurs in a Traffic Modem, and the Redundant Modem operation is fault-free,
backup
is initiated once the configured Backup Holdoff Period lapses. However, if the
fault clears within the holdoff’s configured timeframe, no transfer of operation occurs.
Similarly, if a fault occurs in the Redundant Modem, and the Traffic Modem’s operation
is fault-free, restore is initiated once the configured Restore Holdoff Period lapses.
The default holdoff period is 10 seconds (a minimum of 1 second and a maxium of 99 seconds is
allowed).
5.5.3.4.1 Set Backup Holdoff Period
If a Traffic Modem fails, the Switch waits for the backup holdoff time to determine two things:
1) Does the Traffic Modem remain faulted?
and
2) Is the Redundant Modem not exhibiting the same fault?
If the answer is yes to both questions for the entire backup holdoff time, then the Switch first
bridges the faulted modem with the Redundant Modem. If the fault is sustained, then the
switchover to the Redundant Modem is completed and the Redundant Modem carries the traffic.
There will be no switchover if the Redundant Modem is faulted. Ensure that the Holdoff times are
long enough (default = 10 seconds) for the Redundant Modem to be configured and to lock onto
the signal.
Note: If the CDM-Qx/QxL configuration includes Carrier-in-Carrier
®
this holdoff time should be
no less than 8 seconds.
To set the Backup Holdoff Period :
Step Procedure
1 Go to the CONFIG Æ OPTIONS Æ HOLDOFFS menu.
2 Change the BACKUP HOLDOFF to any number in the range of 1 to 99 seconds.