Resynchronizing a replicated database

If a database falls out of sync, you can mark it as needing recovery. You can then resynchronize the marked database while not affecting other databases in the replication set. The marked database goes offline, but the data in the in-sync databases continues to be replicated and replayed on each replica.

About this task

The following steps provide a general overview of the process. For a complete explanation and example, see nzreplanalyze command.

Procedure

Manually mark the database as needing recovery by issuing the following command:
```
ALTER DATABASE <db> REPLICATION NEEDS RECOVERY FOR <subordinate>
```
Using the nzreplanalyze -needsrecovery command with, as appropriate, the -sub and -db options, further refine the list of databases to resynchronize:
```
nzreplanalyze -recoveryfile <fileName> -set repslet
-needsrecovery -sub <subordinateName>
```
Back up the databases by issuing the nzreplbackup command, using the recovery file that the nzreplanalyze command generated and the appropriate transfer option, such as -dir or -pts:
```
nzreplbackup -recoveryfile <fileName> <transferOption>
```
Restore the databases on the replica by issuing the nzreplrestore command:
```
nzreplrestore -recoveryfile <filePathAndName>
```
If necessary, reactivate the nodes by issuing the following command:
```
ALTER REPLICATION NODE repslet.<subordinateName> STATE ACTIVE
```