Technical data

Using BACKUP
11.5 Understanding Save Sets
BACKUP can read a sequential-disk save set either as a sequential-disk save set
or as a Files–11 save set:
• When BACKUP reads a save set as a sequential-disk save set, the save set
can be mounted one volume at a time. The default directory for the save set
file specification is the master file directory [000000] on the disk.
• When BACKUP reads a save set as a Files–11 save set, all volumes of the
save set must be mounted. The default directory is your process default
directory. Therefore, you must specify the master file directory [000000] in
order to read a sequential-disk save set as a Files–11 save set.
11.6 Understanding BACKUP File Formats
On VAX systems, BACKUP saves files and directories from Files–11 Structure
Level 1 and 2 disks to disks or magnetic tapes. If necessary, you can use
BACKUP to restore the saved files and directories to Files–11 Structure Level 1
and 2 disks.
If a VAX system performs image backup of an Alpha system disk, a restore
operation causes the Alpha system to reboot successfully.
On Alpha systems, BACKUP can save files and directories from Files–11
Structure Level 2 or 5 disks to either disks or magnetic tapes. If necessary, you
can use BACKUP to restore the saved files and directories to Files–11 Structure
Level 2 or 5 disks.
Note
The OpenVMS Alpha operating system does not support the Files–11
Structure Level 1 format.
You cannot back up files on ISO 9660-formatted media, but you can restore save
sets stored on ISO 9660-formatted media.
For more information about the Files–11 disk structure, see Section 9.1.1.2. For
more information about ISO 9660 devices, see Section 8.2.2.
11.7 Setting Process Quotas for Efficient Backups
You can optimize the efficiency of backups on your system by properly setting
the process quotas for the process from which backups will be made (the process
from which you enter the BACKUP command or submit your backup command
procedure). This is especially important if you are using a streaming tape drive.
How to Perform This Task
To set process quotas for efficient backups, perform the following actions:
1. Determine which account you want to use for backups. You can use an
existing account, or create one solely for backups. For information about
creating accounts, see Section 7.6.
2. Use the Authorize utility (AUTHORIZE) to determine the current quota
values for the account you will use for backups. For example, if you are using
the SYSTEM account for backups, enter the following commands:
11–10 Using BACKUP