Restoring data by using a mixed restore

You can use mixed restore to reduce the time until urgent data becomes online and available when you need to restore the server. Urgent data is data that you deem as critical to your business operation.

In a mixed restore, you first perform a cold restore of the critical dbspaces (the root dbspace and the dbspaces that contain the physical and logical logs) and the dbspaces containing your urgent data. Because you do not restore all dbspaces, you can bring the server online faster. You then restore the remaining storage spaces in one or more warm restores.

To perform a mixed restore:

  1. Shut down the database server by running the onmode -ky command.
  2. Perform a cold restore of the critical and urgent dbspaces by running the onbar -r command with the list of critical and urgent dbspace names. You can specify a point in time to restore from an older backup.
  3. Start the server by running the onmode -m command.
  4. Synchronize the storage manager by running the onsmsync command.
  5. Perform a warm restore of the remaining storage spaces by running the onbar -r command. You can perform multiple warm restores to prioritize certain storage spaces.

Examples

Example 1: Simple mixed restore
A database server has five dbspaces in addition to the root dbspace: logdbs, dbs_1, dbs_2, dbs_3, and dbs_4. The logical logs are stored in logdbs and the physical log is in the root dbspace. The critical dbspaces that must be restored during the initial cold restore are rootdbs and logdbs. The dbspace that contains urgent data is dbs_1. The following commands shut down the database server, perform a cold restore on the critical and urgent dbspaces, and restart the database server:
onmode -ky
onbar -r rootdbs logdbs dbs_1
onmode -m

After the database server starts, any data stored in rootdbs, logdbs, and dbs_1 dbspaces is accessible.

The following commands synchronize the storage manager and perform a warm restore of the remaining dbspaces, dbs_2, dbs_3, and dbs_4:
onsmsync
onbar -r 
Example 2: Point-in-time mixed restore
The following commands perform a cold restore for a subset of the storage spaces (including all critical dbspaces) in the initial cold restore, perform a warm restore for dbspace_2 and dbspace_3, followed by a warm restore of dbspace_4 and dbspace_5, and finally perform a warm restore of all remaining storage spaces:
onbar -r -t "2011-05-10 11:35:57" rootdbs logspace_1 dbspace_1 
onmode -m
onsmsync
onbar -r dbspace_2 dbspace_3
onbar -r dbspace_4 dbspace_5
onbar -r