Restoring Db2 from an offline backup using the restore script

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

The restore script can restore:

  • An encrypted backup
  • An unencrypted backup
  • An external Db2 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 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 restore commands.

Syntax

Read syntax diagramSkip visual syntax diagram /db2u/scripts/db_restore_extdb.sh --bkp-dirdirectory--bkp-tarfilename --bkp-timestamptimestamp --dbnamedbname--dblistlist --keystore-dirdirectory--keystore-tarfilename --drop-default-db --replace --cleanup --verbose --help

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 that contains the backup native encryption keystore. This directory must contain only the keystore files. Choose this option or the --keystore-tar option.

--drop-default-db
Drops the existing databases.
--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:

  1. Save the Db2 database backup images and the native encryption keystore in a single location. For example, /mnt/blumeta0/db2/backup/db2ubkp, which is equivalent to ${BACKUPDIR}/db2ubkp.
  2. The Db2 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 ${BACKUPDIR}/db2ubkp
chown db2inst1:db2iadm1 ${BACKUPDIR}/db2ubkp
  3. Run the following command to restore the backup:
    db_restore_extdb --bkp-dir ${BACKUPDIR}/db2ubkp --dbname dbname --bkp-timestamp timestamp --replace --keystore-dir ${BACKUPDIR}/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.

    Note: If your backup was copied from a different instance or remote cluster, you must use the --drop-default-database parameter, instead of the --replace parameter.

Restoring an unencrypted backup

To restore an unencrypted backup, follow these steps:

  1. Save the Db2 database backup images in a single location. For example, /mnt/blumeta0/db2/backup/db2ubkp, which is equivalent to ${BACKUPDIR}/db2ubkp.
  2. The Db2 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 ${BACKUPDIR}/db2ubkp
chown db2inst1:db2iadm1 ${BACKUPDIR}/db2ubkp
  3. Run the following command to restore the backup:
    db_restore_extdb --bkp-dir ${BACKUPDIR}/db2ubkp --dbname dbname --bkp-timestamp timestamp --replace

    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 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.