11.5. Restoring a backup clone

A basic assumption of performing backups is that eventually someone will need to restore old state of a volume. To do this they should contact the system administrator, specifying the volume and the date of the state they wish to restore.

The system administrator must then determine which dump files contain the state. There could be more than one involved since the state may have been captured by a full and some incremental dumps. Once the administrator knows the dates of the backups involved, she must get the appropriate tapes and extract the dump files (via the extract.sh script).

The administrator then creates the full state to be restored by iteratively applying the incremental backups to the full state via the merge program. Once the state for the date in question has been restored, a read-only clone is created by choosing a server to hold the clone, and invoking the volutil restore operation, directing the call to the chosen server. Once the clone has been restored, the administrator should build a new VLDB, and mount the volume in the Coda name space so the user can access it. When the user has finished with it, she should notify the administrator in order for the clone to be purged. (see also Q: 8.3.3. )