DDS Tape Module

Backup Routines

Storing DDS Tape Cartridges

DDS tape cartridges can be stored for a period of 10 years without loss of data. You should give each DDS tape cartridge in storage a full pass in the tape module at least once a year to prevent the tape media from sticking to itself. Store cartridges in a cool, dry environment.

Backup Routines

Your backup routine depends on how frequently the data changes, how extensive the changes are, and how valuable the data is. It is essential that you follow a routine, so data backup is regular and trouble- free. The following three models present routines which are commonly used. In each model, a "set" of DDS tape cartridges is the smallest number of cartridges that will hold a full or partial backup. Keep a record of the number of times each set is used, so a set can be replaced when its recommended write life (100 insertions) is reached. The replaced set can still be kept for read-only use, but should not be used for writing.

Model 1: Daily Backup

Number of cartridges needed: 1 set for full backup

This is the simplest backup model. All of your data is backed up onto a single set of cartridges at the end of each work day. If data is lost, it is simply restored from the previous day's backup. It is the least secure backup model because if the cartridge is lost, destroyed, or damaged, the data is lost forever.

Model 2: Weekly Rotation with Daily Backup

Number of cartridges needed: 2 sets for full backup

4 sets for partial backup

In this model, you perform a full backup every Friday, and a partial backup on Monday, Tuesday, Wednesday, and Thursday. Partial backups are made only on those files that have changed since the previous backup.

Two sets of cartridges, A and B, are used in rotation for the weekly full backups. On the first Friday, you make a full image copy of your disks on set A. On the second Friday, use set B for a full backup. On the third Friday, use set A again. This way, there are always two generations of full backup in existence. Store the sets off-site, preferably in a fire-proof safe.

Four sets of cartridges are used for the daily backups, one set for each day. Because only changed files are saved, these backups are very quick.

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DDS Tape Module