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Disaster Recovery Planning


Disaster Recovery Planning

No one is safe from disaster. A disaster can be a fire that burns your company building to the ground, a flood, an earthquake, a major system failure, or even sabotage .

Backing up is not enough to protect yourself from disaster. In the event of a fire or earthquake, having tapes with everything you ever had on the system doesn't do you any good if you don't have a system to restore them to. Therefore, you must devise a safe and sound disaster recovery plan.

A discussion of such a plan (or even a complete definition) is beyond the scope of this book. Firms exist whose primary business is providing a disaster recovery plan for computer users. You should contact one of them immediately.

A well-implemented disaster recovery plan can offer you a replacement system that will be available if your system becomes unusable. The disaster recovery supplier charges a fee for this service, but you can look at it as a form of insurance. The provider works with you and helps you design a good disaster recovery plan.

Tip 

Once you have a plan in place, follow the guidelines religiously and test it thoroughly. Sometimes you think the plan is fool proof, only to later discover holes in it.



Using Save Files

When you perform save and restore operations, you can use save files instead of tapes. Save files are objects of type *FILE that reside on disk. They offer faster backups than those provided by tapes because a save operation to a save file is a copy from disk to disk. In addition, they don't require operator intervention to mount the next tape when one ends.

On the other hand, save files use up (at least temporarily) space on your disk drives .

Using Save Files

To use a save file instead of tape, you must create the save file first, using the Create Save File (CRTSAVF) command. For example:


CRTSAVF FILE(MYLIB/MYSAVF) TEXT('Save file for backups')

To save to the save file, execute the usual save command, except specify DEV(*SAVF) and the name of the save file in the SAVF parameter. Note that the SAVSYS command does not accept DEV(*SAVF). For example:


SAVLIB LIB(ACCTG) DEV(*SAVF) SAVF(MYLIB/MYSAVF)

This command saves the entire ACCTG library in save file MYSAVF in library MYLIB.

At your leisure, some time after this SAVLIB command ends, you can save the save file to tape and clear the save file, which frees precious disk space. To copy save files to tape, use the Save Save File Data (SAVSAVFDTA) command:


SAVSAVFDTA SAVF(MYLIB/MYSAVF) DEV(SYSTAP01)


FILE(MYLIB/MYSAVF)

If you need to restore the ACCTG library from this tape, use the regular RSTLIB command. The system will not care that you used a save file in the process. If you can afford the space on your disk, you may be tempted to leave the save file full of data and never perform the backup to tape. In this case, the RSTLIB command would have to specify DEV(*SAVF) SAVF(MYLIB/MYSAVF). However, with this method, you do not have an external backup that you can keep in a safe place. If your disk crashes and must be replaced , the backup in the save file will be lost too.



Chapter 7: Operational Assistant

Overview

The System/38 is the AS/400's predecessor. CPF, the S/38's operating system, has always been considered sophisticated and difficult to use. When developers at IBM designed the AS/400, they incorporated many of the ease-of-use features of the System/36 into the AS/400.

IBM developed Operational Assistant (OA) in order to make the AS/400 even easier to operate . Because OA was implemented as part of the operating system, it is also available on the iSeries and i5 systems.

OA is comprised of a series of menus , help displays, and prompt displays that guide the system operator through some of the most obscure system commands. Anyone who is responsible for the operation of an i5 system should investigate and use OA.