Rollback And Snmp; Rescue Configuration - Alcatel-Lucent 7450 Basic System Configuration Manual

Rollback and SNMP

The SR OS has SNMP support for Rollback status and control. See the TIMETRA-SYSTEM-
MIB for details (for example, items such as tmnxSysRollbackStarted).
When the router is doing a rollback revert, SNMP managers will see a
tmnxSysRollbackStarted trap, then a rapid set of "config change" traps, and then finally, the
tmnxSysRollbackStatusChange trap.
During the period when a router is processing a rollback revert, both CLI commands (from
other users) and SNMP commands will continue to be processed.

Rescue Configuration

A special rescue configuration checkpoint can be created that an operator can rollback revert
to at any time. The rescue configuration has its own keyword (rescue) and does not use the
same rolling suffix indices as the normal rollback checkpoints. This allows the operator to
easily return to the rescue configuration state without having to consider a checkpoint index,
and ensures that the rescue checkpoint is always available (does not roll off the bottom of the
list of checkpoints).
Basic System Configuration Guide
• Although the use of the Control-C key combination is not recommended during a
rollback revert, it is supported (via CLI or SNMP). Interrupting a rollback revert may
leave the router in a state that is not necessarily something between the old active
config and the rollback checkpoint since the rollback processing may have been in
the middle of tearing things down or rebuilding configurations. A strong warning is
issued in this case to indicate that the operator must examine the config and
potentially issue another rollback revert to return to a known (and coherent)
configuration.
• An HA CPM switchover during a rollback revert will cause the rollback operation to
abort. The newly active CPM will have an indeterminate configuration. When an HA
switchover occurs during a rollback (or within a few seconds of a rollback
completing), the operator is advised to repeat the rollback revert operation to the
same checkpoint.
• A rollback revert operation does not check authorization of each command that is
applied during the revert. Permission to execute the revert operation (authorization
for the "admin rollback revert" command itself) should only be given to users who
are allowed to initiate a rollback revert. It is generally advised to only allow system
administrators access to the file system where the rollback files are stored so that they
cannot be manually edited.
CLI Usage
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