Performing Physical Restore for a Full-System Cold (SAP Library - SAP Database Guide: Informix (BC-DB-INF-DBA))

Performing Physical Restore for a Full-System Cold Restore (ON-Bar)

Use

This is the second stage in a full-system cold restore of the Informix database if you use ON-Bar as your data recovery tool (that is, for your database and logical-log backups). This procedure restores only the data from backups of the storage spaces. You restore logical-log data in the logical restore phase.

By default, ON-Bar uses the most recent backup for the restore, as listed in the ON-Bar emergency boot file. ON-Bar always takes the following level-1 and level-2 backups if available.

Prerequisites

You are logged on as user informix or root .

The database server is offline.

You know which backup to use for the restore, and have made sure that the relevant storage media are available to the storage manager.

If required, you have completed Salvaging Logical Logs for a Full-System Cold Restore (ON-Bar).

Procedure

Enter the ON-Bar command to perform the physical restore.

· If you are restoring from a whole-system backup, enter the following:

$ onbar -r -p -w

· If you are restoring from a storage-space backup, enter the following:

$ onbar -r -p

The storage manager requests the required storage media and executes the physical restore.

Check the results of the physical restore by looking in the ON-Bar activity log or the message log. You can view the message log with SAPDBA. Refer to Listing System Information with SAPDBA.

Example

Here is an example from the ON-Bar activity log of the physical restore phase of a whole system restore with onbar -r -w -p :

1998-12-18 16:01:01 16715 16713 /.../bin/onbar_d -r -w -p

1998-12-18 16:01:15 16715 16713 Successfully connected to Storage Manager.

1998-12-18 16:01:17 16715 16713 Begin cold level 0 restore rootdbs.

1998-12-18 16:01:40 16715 16713 Completed cold level 0 restore rootdbs.

1998-12-18 16:01:44 16715 16713 Begin cold level 0 restore dbs1.

1998-12-18 16:01:44 16715 16713 Completed cold level 0 restore dbs1.

This is the message log from the same restore :

16:01:26 Recovery Mode

16:01:29 Physical Restore of rootdbs, dbs1 started.

16:01:41 Checkpoint Completed: duration was 0 seconds.

16:01:45 Checkpoint Completed: duration was 0 seconds.

16:01:47 Physical Restore of rootdbs, dbs1 Completed.

16:01:47 Checkpoint Completed: duration was 0 seconds.

Here is an example from the ON-Bar activity log of the physical restore phase of a parallel storage-space restore with onbar -r -p :

1998-12-18 17:15:47 17108 17106 /.../bin/onbar_d -r -p

1998-12-18 17:16:01 17108 17106 Successfully connected to Storage Manager.

1998-12-18 17:16:04 17108 17106 Begin cold level 0 restore rootdbs.

1998-12-18 17:16:24 17108 17106 Completed cold level 0 restore rootdbs.

1998-12-18 17:16:28 17122 17108 Process 17122 17108 successfully forked.

1998-12-18 17:16:28 17122 17108 Successfully connected to Storage Manager.

1998-12-18 17:16:31 17122 17108 Begin cold level 0 restore dbs1.

1998-12-18 17:16:31 17122 17108 Completed cold level 0 restore dbs1.

1998-12-18 17:16:34 17122 17108 Process 17122 17108 completed.

1998-12-18 17:16:34 17108 17106 WARNING: Physical restore complete .

Logical restore required before work can continue.

This is the message log from the same restore :

17:16:12 Recovery Mode

17:16:15 Physical Restore of rootdbs started.

17:16:24 Checkpoint Completed: duration was 0 seconds.

17:16:27 Physical Restore of rootdbs Completed.

17:16:27 Checkpoint Completed: duration was 0 seconds.

17:16:28 Physical Restore of dbs1 started.

17:16:31 Checkpoint Completed: duration was 0 seconds.

17:16:34 Physical Restore of dbs1 Completed.

17:16:34 Checkpoint Completed: duration was 0 seconds.

What you do now depends on the type of restore you are doing:

If you are restoring from a parallel storage-space backup, you must now perform a logical restore because the logical logs are needed to synchronize the backup. This requirement is mentioned in the activity log (see the example above):

Logical restore required before work can continue.

If you are restoring from a whole-system backup, you can bring the database server back up without a logical restore and the database is consistent. If you want to apply logical-log data to bring the database more up to date, you can do so.

To leave out the logical restore phase of a whole-system restore, do the following:

a. Use SAPDBA to change server mode to quiescent.

b. Use SAPDBA to change server mode to online.

Refer to Changing Server Mode with SAPDBA.

However, SAP recommends you to perform a logical restore if you have the necessary logical-log backups.

Result

Now that you have performed the physical restore the database server goes into fast-recovery mode. You can go on to the next stage, Performing Logical Restore for a Full-System Cold Restore (ON-Bar).

See also:

Informix documentation