Setting Up Storage Media for Database Backup (ON-Bar)
Setting Up Storage Media for Database Backup (ON-Bar)
Use
You need to set up enough storage media – for example, tape volumes – with adequate capacity for Informix database backup with
ON-Bar .Procedure
Keep in mind the following when you choose storage media for database backup:
The amount of data you need to back up determines the amount of space on your storage media required for a database backup.
For example, how often you perform database backup and at what level influences the storage space required. A database backup at level-0 requires more storage space than at level-1 or level-2.
The longer you keep your database backups before overwriting them, the more storage media required. The recommended period is 28 days or longer.
The following examples illustrate the number of tape volumes required for backing up a normal and a large database:
This example is for backup of a normal database, assuming a four week (28-day) cycle (that is, the tapes are reused after this period).
Assume you want to perform database backup at level-0 (full) daily during the working week (Monday to Friday). This requires two tape volumes for each database backup.
Then you need:
2 volumes a day x 5 days per week x 4 weeks = 40 volumes
This example is for backup of a large database, assuming an eight week (56-day) cycle (that is, the tapes are reused after this period).
Assume you want to perform database backup at level-0 (full) once a week on the weekend and this requires four volumes for each database backup. Also assume that you want to perform database backup at level-1 (incremental) daily during the working week (Monday to Friday) and this requires two tape volumes per database backup.
Then you need:
· Level-0 database backups:
4 volumes a week x 8 weeks = 32 volumes
· Level-1 database backups:
2 volumes a day x 5 days a week x 8 weeks = 80 volumes
Therefore, you need 112 tape volumes in total.
Result
You have set up storage media for optimal database backup with
ON-Bar .