HP 3162 - Manual (Page 63)

Configuration
4-21 3162-A2-GB20-40 August 2000
Providing Backup Capability
If the T1 network fails, the DSU/CSU provides the ability to reconfigure the unit
and restore (at least partially) priority data circuits through an external backup
device.
You can store backup configuration options in the Customer 2 set of
customer-defined configuration options. The Enterprise MIB variable
devConfigAreaCopy allows the entire contents of one configuration area to be
copied into another configuration area via SNMP.
By cross-connecting two synchronous data ports to each other, one port can
provide a backup path for the other. As soon as the ports are configured to be
mapped to each other, Data Set Ready (DSR) for the ports is turned on. The
external backup device can be configured to initiate dialing when it detects the
off-to-on transition of DSR.