Technical data

Using BACKUP
11.17 Backing Up and Restoring the System Disk
11.17 Backing Up and Restoring the System Disk
Backing up your system disk is critical for the following reasons:
• A system disk could become inoperable if a problem occurs during a software
upgrade, update, or installation. Before you attempt any of these operations,
back up the system disk. If a problem occurs, you can restore the backup
copy of the system disk.
• System files could inadvertently be deleted. After you install, upgrade, or
update the operating system or any other software products, back up the
system disk. If a system file is deleted, you can restore the backup copy and
continue to use the system.
• The drive that holds the system disk could malfunction. If you have a backup
copy of the operating system and your other software, you can restore it to a
functioning disk and continue to use the system.
• Disk fragmentation could occur if files are stored noncontiguously on the
disk. Perform an image backup of the system disk to a magnetic tape or
another disk and then restore the files to the original system disk. This
restores the system disk and contiguously stores files. You can also eliminate
fragmentation by performing a disk-to-disk image backup without using the
/SAVE_SET qualifier. This creates a functionally equivalent copy of the entire
system disk, on which files are stored contiguously. (See Section 11.17.5.)
If you have access to the OpenVMS Alpha or VAX operating system distribution
compact disc, back up your system using the menu system provided on the disc.
For more information about using the menu system, see Section 11.17.1.
Note
If you use the menu system to back up large system disks on low memory
VAX systems (those with less than 32 MB of memory), BACKUP might
need to page and thereby cause the operation to fail. If this problem
occurs, use standalone BACKUP to back up system disks on VAX systems.
If you do not have access to the OpenVMS VAX operating system distribution
compact disc, use standalone BACKUP to back up and restore your system disk.
For more information about standalone BACKUP, see Section 11.17.2.
11.17.1 Starting the Menu System
Use the menu system in this section to back up or restore system disks and user
disks if you have access to the OpenVMS Alpha or VAX Version operating system
distribution compact disc.
How to Perform This Task
1. If the operating system is not running, go to step 2.
If the operating system is running, log in to the SYSTEM account. Enter the
following command and press Return:
$ @SYS$SYSTEM:SHUTDOWN
Using BACKUP 11–51