Mocomtech CRS-300 operation manual Set Holdoff Period, Set Backup Holdoff Period

CRS-300 1:10 Redundancy Switch	Revision 16
Modem, RMI/TMI, and Switch Configuration	MN/CRS300.IOM

To enable Auto mode:

Step Procedure

1Go to the CONFIG Æ AUTO menu and turn on AUTO mode.

2Verify that the Stored Event LED stops blinking.

5.5.3.4Set 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).

5.5.3.4.1Set 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.

5–23