Line Backup 8-11

Note: For best results, enter an IP address and not a host name. If a host name is used it may not be resolvable, and may keep the interface down.

Set the Ping Host Name or IP Address to the router's Default Gateway, or other reliable IP address elsewhere on the backbone – for example, a DNS server. This will ensure that the router will initiate backup connection on loss of Layer 3.

Note: If you want the router to initiate the backup connection on loss of Layer 1 or 2 only (Physical or Data link Layer), leave Ping Host Name or IP Address blank. Do not use 0.0.0.0 in this field. Hit the space bar or Delete key to CLEAR the field totally. Leaving 0.0.0.0 in this field tells the router to ping an address that does not exist.

Select Recovery to ADSL and press Return. Choose either Manual or Automatic to determine how the system will return to the primary WAN link when it becomes available again. If you choose Automatic, the next two menu items become visible.

Note: Automatic recovery only works upon loss of primary WAN connectivity.

If you chose Automatic Recovery, select Requires Recovery of (seconds) and enter the number of sec- onds that the system should wait before it assumes that a connection has been re-established. This allows you to be sure that the primary WAN connection is well re-established before the router switches back to it from the backup mode. If the router's primary connection fails at layer 1, the Requires Recovery of (seconds) parameter determines the amount of time the primary layer 1 con- nection must be up (recovered) before the router will tear down the backup connection and revert to the primary interface. Minimum value is 10 seconds.

Select Clear Backup Call only if idle. The default Yes will prevent the backup call from being torn down if there is activity on the backup connection when the primary connection comes back up. You can toggle this to No if you wish.

The Clear Backup Call only if Idle timer is a separate timer from the Requires Recovery of (seconds) timer. The router will first reach the Requires Recovery of (seconds) counter and count down to zero. Then the router will consult the Clear Backup Call only if Idle timer to learn if the backup connection has been idle for the specified seconds. If the connection has been idle for the specified seconds, then the teardown process of the backup connection will begin.

Requires idle time of (seconds) specifies how long the device should wait before permitting the call to be torn down after a period of inactivity.

Toggling Backup mode disables RIP/Primary to Yes (disabled) allows you to disable RIP services on the primary WAN interface when the Router is in Backup mode. RIP services ordinarily will continue to run on the primary interface when in Backup mode, attempting to determine “layer 2” connectivity.

Usually, the default No setting is desirable, since it may be required to ping the configured host that determines “layer 2” connectivity. However, RIP running on the recovering primary interface may cause problems specific to your application. When in Backup mode, RIP routes are still sent and received through the primary interface, even though that is not the active interface.

Data Link Encapsulation is Async PPP – if it appears (not on all models) this field is not editable.

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Motorola Enterprise Series Routers, 6161252-00-01 manual Line Backup