User's Manual
Backup and Restore of administered data of Network Management applications
98 Network Management Configuration
backup the data using the NM Backup Utility the data from the PostgreSQL database also gets
backed up.
When you restore the backed up data using the NM Easy Restore utility, all the data entered in
the database after the backup operation is not included in the restore. It is lost. However, it is
possible to recover this data using the PostgreSQL database feature called WAL (Write Ahead
log) archiving.
Using this feature, PostgreSQL remembers the date and time you took the last backup and all
the data entered thereafter is maintained separately in a log file called “write ahead log” (WAL)
in its internal directories.
During restore, if ‘Recover PostgresSQL database using write ahead logs (WAL)’ is
selected, the NM Easy Restore utility attempts to restore this data using the latest WAL file
along with the backed up data bringing the database to the current state with all the entries in it.
Following conditions should be met for successful restore using the Recover PostgresSQL
database using write ahead logs (WAL) option:
l The backup archive you restore from should be the latest backup taken. This is necessary
because the current WAL files are with respect to the latest backup date and time. If you
choose an old backup archive the entries in the WAL file cannot be restored.
l The application should not be reinstalled after the backup. If you reinstall the application
anytime after backup, the WAL files stored by database get deleted and hence you will not
be able to restore the database in the current state. In such case, the database will be
restored to the same state as it was during backup. The restore utility does not report any
error even if the WAL files are not in expected sequence.
Note:
Note: You can use the NM Backup Utility to take backup of data and settings of Network
Management Console, Provisioning and Installation Manager for Gateways, and
Provisioning and Installation Manager for IP Office applications. Of these only
Network Management Console uses the PostgreSQL database. Recover
PostgresSQL database using write ahead logs (WAL) option has no significance
for Provisioning and Installation Manager (PIM) applications restore.
Do not select the option "Recover PostgresSQL database using write ahead logs
(WAL)" if the last restore attempt failed.