Performing Logical Restore for a Full-System Cold Restore (ON-Bar)
Use
This is the final stage in a
full-system cold restore if you use ON-Bar as your data recovery tool (that is, for your database and logical-log backups). This section includes how to do a "Point-in-Time" (PIT) and a "Point-in-Log" (PIL) restore.
Logical restore is not compulsory. For example, with a whole system restore, if you cannot use the logical logs for some reason (that is, they have been damaged or lost), you can restart the database after the physical restore and it is consistent but less up-to-date. See the final step in
However, when you restore from a storage-space backup, you must also perform a logical restore, because the logical logs from the time of the backup are needed to synchronize the backup.
Prerequisites
Procedure
$ onbar -r -l
If you want to perform a PIL or PIT restore, enter data as required. For example, the following command restores data to a PIT of 11:30 in the morning of the 5th of February 1999:
$ onbar -r -t
"1998-02-05 11:30:00"Note that the format of the above command depends on your locale settings. Refer to the Informix documentation.
For example, the following command restores data to a PIL of the third logical-log file (that is, if there are any logical-log files after this one, they are not used):
$ onbar -r -n 3
The storage manager requests the required storage media and executes the logical restore.
Here is an example of a logical restore from the
ON-Bar activity log:1998-12-18 16:06:24 16747 16745 Begin restore logical log 4.
1998-12-18 16:06:28 16747 16745 Completed restore logical log 4.
1998-12-18 16:06:33 16747 16745 Begin restore logical log 4.
1998-12-18 16:06:37 16747 16745 Completed restore logical log 4.
1998-12-18 16:06:42 16747 16745 Begin restore logical log 5.
1998-12-18 16:06:42 16747 16745 Completed restore logical log 5.
1998-12-18 16:06:45 16747 16745 Begin restore logical log 6.
1998-12-18 16:06:46 16747 16745 Completed restore logical log 6.
1998-12-18 16:06:49 16747 16745 Begin restore logical log 7.
1998-12-18 16:06:50 16747 16745 Completed restore logical log 7.
1998-12-18 16:06:54 16747 16745 Begin restore logical log 8.
1998-12-18 16:06:54 16747 16745 Completed restore logical log 8.
1998-12-18 16:06:57 16747 16745 Begin restore logical log 9.
1998-12-18 16:06:58 16747 16745 Completed restore logical log 9.
Here is an example of a logical restore from the message log:
16:06:19 Logical Recovery Started.
16:06:19 Checkpoint Completed: duration was 0 seconds.
16:06:19 Start Logical Recovery - Start Log 9, End Log ?
16:06:19 Starting Log Position - 9 0xfa0cc
16:06:31 Checkpoint Completed: duration was 0 seconds.
16:06:38 Checkpoint Completed: duration was 2 seconds.
16:06:39 Checkpoint Completed: duration was 0 seconds.
16:06:50 Checkpoint Completed: duration was 0 seconds.
16:06:50 Checkpoint Completed: duration was 0 seconds.
16:06:50 Checkpoint Completed: duration was 0 seconds.
16:06:54 Checkpoint Completed: duration was 1 seconds.
16:06:54 Checkpoint Completed: duration was 0 seconds.
16:06:54 Checkpoint Completed: duration was 0 seconds.
16:06:55 Checkpoint Completed: duration was 0 seconds.
16:06:55 Checkpoint Completed: duration was 0 seconds.
16:06:58 Checkpoint Completed: duration was 0 seconds.
16:06:58 Checkpoint Completed: duration was 0 seconds.
16:06:58 Checkpoint Completed: duration was 0 seconds.
16:06:58 Checkpoint Completed: duration was 0 seconds.
16:07:04 Logical Recovery Complete.
187 Committed, 1 Rolled Back, 0 Open, 0 Bad Locks
16:07:04 Logical Recovery Complete.
16:07:05 Quiescent Mode
16:07:05 Logical Log 9 Complete.
16:07:05 Checkpoint Completed: duration was 0 seconds.
You can view the message log with SAPDBA. Refer to
Listing System Information with SAPDBA.After the logical restore, the database server is in quiescent mode.
Refer to
Result
The database is now restored and you can use the R/3 System productively again.
See also:
Informix documentation