Using the restore script

You can use a provided script file to restore Db2® Warehouse backup images, with or without encryption.

The restore script can restore:

An encrypted backup
An unencrypted backup
An external Db2 Warehouse database from the same or different form factor (such as a bare metal Db2 deployment within the same platform family)
The backup from an earlier Db2 Warehouse version

The following sections provide usage information for the db_restore_extdb.sh script, and details on using the script to restore with different options.

Note: You can only use the script to restore full offline backup images. If you are using incremental/online backup images, use the native Db2 Warehouse restore commands.

Syntax
Restoring an encrypted backup
Restoring an unencrypted backup
Restoring an external database

Syntax

Options:

--bkp-dir directory: Specifies the directory where the backup images are located. Choose this option or the --bkp-tar option.
--bkp-tar filename: Specifies a .tar file that contains the backup images.
--bkp-timestamp timestamp: The timestamp of the backup image to use for the restore.
--dbname dbname: The name of the database to use when restoring the backup image.
--dblist: A comma-separated list of database names to use when restoring the backup image.
--keystore-dir directory: The directory where the backup native encryption keystore is located. Choose this option or the --keystore-tar option.
--drop-default-db: Drops the existing databases. This keyword must be included when you restore a Db2 Warehouse database.
--replace: Replaces the existing database.
--keystore-tar: Specifies a .tar file that contains the backup native encryption keystore.
--cleanup: Specifies to clean up all backup images.
--verbose: Use this flag to view explicit commands that the script is performing or to view errors.
--help: Use this flag to display help for the tool.

Restoring an encrypted backup

To restore an encrypted backup, follow these steps:

Save the Db2 Warehouse database backup images and the native encryption keystore in a single location. For example, /mnt/backup/db2ubkp.
The Db2 Warehouse instance owner/group must have read-write access to the backup directory where the backup images and keystore files are saved. You can set the required mode-bits and permissions by issue a command:
```
chmod 755 /mnt/backup/db2ubkp
chown db2inst1:db2iadm1 /mnt/backup/db2ubkp
```
Run the following command to restore the backup:
```
db_restore_extdb --bkp-dir /mnt/backup/db2ubkp --bkp-timestamp timestamp --drop-default-db --keystore-dir /mnt/backup/db2ubkp
```
Replace dbname with the case-sensitive database name, and timestamp with the timestamp of the backup image. You can obtain the output log for the restore command by running cat ${SUPPORTDIR}/db_restore_extdb.log.

Restoring an unencrypted backup

To restore an unencrypted backup, follow these steps:

Save the Db2 Warehouse database backup images in a single location. For example, /mnt/backup/db2ubkp.
The Db2 Warehouse instance owner/group must have read-write access to the backup directory where the backup images and keystore files are saved. You can set the required mode-bits and permissions by issue a command:
```
chmod 755 /mnt/backup/db2ubkp
chown db2inst1:db2iadm1 /mnt/backup/db2ubkp
```
Run the following command to restore the backup:
```
db_restore_extdb --bkp-dir /mnt/backup/db2ubkp --bkp-timestamp timestamp --drop-default-db 
```
Replace dbname with the case-sensitive database name, and timestamp with the timestamp of the backup image. You can obtain the output log for the restore command by running cat ${SUPPORTDIR}/db_restore_extdb.log.

Restoring an external database

The backup image (and keystore, if encrypted) can also be restored from an external source. For example, you might want to re-initialize Db2 Warehouse by using a database from an on-premises deployment.

You can use the --dbname dbname option to set the database name to the same as the source in this scenario.