Nortel BCM 3.7, Manual

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Programming Operations Guide
Chapter 36
Configuring Net Link Manager
Net Link Manager is a Business Communications Manager service that provides constant primary
link status monitoring. Net Link Manager is also where you select your WAN primary and backup
interfaces.
This section contains information about enabling/disabling Net Link Manager, as well as how to
select WAN links:
• “Enabling or Disabling Net Link Manager” on page 734
• “Selecting a permanent WAN link as the primary WAN connection” on page 734
• “Selecting a dial-up link as the primary WAN connection” on page 736
When Net Link Manager detects a primary WAN link failure, Net Link Manager automatically
establishes a backup WAN connection, if one is configured. Net Link Manager monitors the WAN
primary link by performing multiple tests. When a predetermined number of tests fails, Net Link
Manager establishes the backup connection.
The backup connection uses a V.90 modem or one or more ISDN B-channel s . When the backup
WAN connection is active, Net Link Manager continues to monitor the status of the primary WAN
link connection. When the primary WAN link connection is determined to be available again, Net
Link Manager re-establishes the primary WAN link and disconnects/disables the backup
connection.
Warning: If dial-up connection is used as the primary WAN connection, no backup link
is available.
Note: Net Link Manager manages the default route in Business Communications
Manager. If the primary link fails, Net Link Manager removes the default route from the
Primary link and adds it to the backup link. This happens during the switch over from
primary to backup link. The default route returns to the primary link after the connection
to the primary WAN link is re-established.