Creating system backups

You can create and verify a bootable backup copy, or mksysb image, of your root volume group. You can also make separate backup copies of user volume groups.

The root volume group is a hard disk or group of disks that contains:

  • Startup files
  • Base Operating System (BOS)
  • System configuration information
  • Optional software products

A user volume group, also called the nonroot volume group, typically contains data files and application software.

A system backup does the following:

  • Contains a working copy of your system. In the event your system data becomes corrupted, you can use this information to restore your system to working order.
  • Allows you to transfer installed and configured software from one system to others. You can use the SMIT to make a backup image of the root volume group or user volume groups.

A backup transfers the following configurations from the source system to the target system:

  • rootvg volume group information
  • Paging space information
  • Logical volume information
  • Placement of logical partitions (if creating map files has been selected in SMIT).
    Note: The use of map files is not recommended if you plan to reinstall the backup to target systems other than the source system, or the disk configuration of the source system is to be changed before reinstalling the backup.

Using the SMIT backup menu lets you preserve configuration information, thus avoiding some of the configuring tasks normally required after restoring a system backup. A backup preserves the configuration if the following are true:

  • The target system has the same hardware configuration as the source system.

    AND

  • The target disk has enough space to hold the backup image.

The SMIT uses the mksysb command to create a backup image, stored either on CD, DVD, removable hard disk cartridge, tape, or in a file. If you choose CD, DVD, removable hard disk cartridge, or tape, the backup program by default writes a boot image, which makes the medium suitable for installing. For more information, see Creating a system backup to CD-R, DVD-R, or DVD-RAM.

If you have problems with installations from a mksysb image, see Troubleshooting problems with installation from mksysb backup.