Comtech EF Data CRS-300 - Manual (Page 191)

CRS-300 1:10 Redundancy Switch MN/CRS300.IOM
Modem, RMI/TMI, and Switch Configuration Revision 19
5–27
5.6.2.3 Set the Switch Operation Mode
When in AUTO-OFF (manual) mode:
• Although the system is operational, this operational setting causes the Stored Event LED to
blink.
• You may manually select which Traffic Modem to bridge or back up.
• The Switch does not automatically react to any Traffic Modem failures it detects.
Comtech EF Data recommends that you configure an unattended system to operate in AUTO
mode. When you enable AUTO mode, the first active modem that fails is first bridged by the
Redundant Modem, and then backed up.
Use the CRS-300 Front Panel menu to enable AUTO mode (make sure to press [ENT] to save
your changes). Do these steps:
Step Task
1 Use the [←][→] keys to select the CONFIG: AUTO menu.
2 Select AUTO mode
3 Verify that the Stored Event LED stops blinking.
5.6.2.4 Set the Holdoff Period
A holdoff period prevents unwarranted backups due to an intermittent fault. In AUTO mode,
you may introduce additional delays into the backup procedure. Do this by setting the number
of seconds for "holdoff" – i.e, the time specified 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 maximum of 99 seconds
is allowed).
Comtech EF Data ships the Switch in the AUTO-OFF (manual) operating mode. The
CRS-300 Front Panel menu identifies this manual mode as AUTO-OFF.