6.7.3 Notes on backup acquisition

Organization of this subsection
(1) Backup acquisition units
(2) Checking the status of JP1/OmniBack II
(3) Backup acquisition example

(1) Backup acquisition units

If there is a large volume of data, do not back up all RDAREAs into a single object. If all RDAREAs are backed up into a single object, restoration of a specific RDAREA will take a long time because the RDAREAs must be loaded sequentially. Therefore, it is recommended that RDAREAs be divided into groups for making backups.

For example, when a disk error occurs, RDAREAs are restored one disk at a time, so it is recommended that the backup of a single disk be collected into a single object.

(2) Checking the status of JP1/OmniBack II

Execute the omnistat command of JP1/OmniBack II to check the status of JP1/OmniBack II during execution of the pdcopy or pdrstr command.

(3) Backup acquisition example

In this example, multiple backup generations are saved.

Conditions
  • Slots 1, 2, and 3 of the DLT library are defined in logical device 1 of JP1/OmniBack II.
  • Slots 4, 5, and 6 of the DLT library are defined in logical device 2 of JP1/OmniBack II.
Operation example
  1. The first backup is collected as object 1 on November 30, 2000, into logical device 1. The protection expiration date is set to December 13, 2000.
  2. The second backup is collected as object 2 on December 7, 2000, into logical device 2. The protection expiration date is set to December 20, 2000.
  3. The third backup is collected as object 1 on December 14, 2000, into logical device 1. The protection expiration date is set to December 27, 2000.

When the protection expiration dates are specified in this overlapping manner, the medium is reused efficiently.

Note that if permanent protection is specified, you must use JP1/OmniBack II's omnidb command to release object protection when the third and subsequent backups are made.