Data Protection
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Titan SiliconServer
To Back Up a Database
1.
For databases, shut down the database or use a database-specific command to bring
database files into a consistent state.
2.
Take a snapshot of the file system.
Note:
It is possible to associate the snapshots taken for this purpose with a
rule, so that a number of snapshots can be kept. This can be done using the
command line interface.
3.
Restart the database.
4.
Make a backup copy of the snapshot.
All four steps can be scripted to automatically backup at pre-defined times.
Incremental Backups and Snapshots
Taking a full backup of a File System can be time-consuming, so it is a good idea to combine
infrequent full backups with regular incremental backups. However, these incremental backups
may fail to capture all the changes in the File System, e.g. if the modification time of a file is the
determining factor in whether or not to back it up, a backup program will not archive the
contents of a directory that has been moved, because the times/dates of the files remain
unchanged.
Snapshots provide a solution to this problem. After taking the initial, base backup using a
snapshot image, it can be used at incremental backup time to obtain a better picture of changes
in the file system. In order to use the snapshots this way, the snapshot must be kept around for
as long as the associated backup may be used as the basis for an incremental backup.
Selecting NDMP Snapshot Options
By default, Titan automatically creates a snapshot before it starts a backup operation. The
backup then proceeds from the snapshot image rather than the file system. However, if the file
system cannot take the snapshot for any reason, the backup proceeds directly from the live file
system.
