STORE and TurboSTORE/iX Products Manual (B5151-90003)

24 Chapter2

Managing Backups and Backup Media

Determining Your Backup Strategy

The TurboSTORE programs allow you to store ﬁles to a single device or to multiple

devices.

The best way to use your backup devices depends upon the characteristics of the ﬁles that

you are storing, your needs for compatibility with other versions of MPE, and your system

conﬁguration.

The characteristics of the set of ﬁles help determine choices (or options) for storing them.

Use the following guidelines to select the most appropriate method:

• How many ﬁles do you need to back up?

Generally, the more ﬁles in the ﬁleset, it is to your advantage to use multiple devices or

a high capacity storage device such as a magneto-optical disk device.

• If you are storing only a few ﬁles of moderate size, one backup device such as a tape

drive or DDS-format device is sufﬁcient.

• If you are storing many ﬁles (for example, all the ﬁles in an account, or a smaller

number of very large ﬁles), a multiple-device backup is best.

• If you need to do small, fast application backups, you may want to use the

store-to-disk feature of TurboSTORE/iX 7x24 True-Online Backup (B5152AA). This

allows you to quickly backup key applications to disk ﬁles.

• Do the backup ﬁles need to be compatible with another system?

Compatibility with other versions of MPE limits your choices. If you need to create

STORE tapes that are compatible with MPE V/E, you must use the TRANSPORT option.

This restricts you to a subset of the available STORE commands, and allows you to only

store to one device. If you need to take ﬁles from a MPE/iX 5.0 or later system to a

pre-5.0 system, you should use the TRANSPORT=MPEXL option. This ensures that various

POSIX features are correctly translated to a pre-POSIX version of MPE.

• Does your system conﬁguration include multiple backup devices?

If you do not need to create backups compatible with older versions of MPE, then your

system conﬁguration is the most important determining factor of which multiple-device

method to use. Use the following guidelines to select a method:

• Which and how many backup devices do you have?

If you have two or three like backup devices, use either parallel or sequential

devices. If you have at least four devices, use two or more parallel device pools.

• Do you intend to use labeled tapes?

Labeled tapes can be used with a single device and parallel devices, but not with

sequential devices. Unlabeled tapes can be used with single, parallel, and sequential

devices.