BOS pre_migration and post_migration checks

The pre_migration and post_migration commands perform various system checks to ensure a successful migration installation. Both commands are shipped in the bos.rte fileset.

In case the pre_migration command does not exist on a level of AIX® that you want to check before performing a migration installation, the pre_migration command is also located in the usr/lpp/bos directory of the media file system. Copy the pre_migration command from the usr/lpp/bos directory of the new AIX media version you are about to perform the migration.

The output from the pre_migration command is saved to the system in the /home/pre_migration date directory.

The pre_migration command performs the following actions:
  • List the device filesets being removed.
  • List all other filesets being removed.
  • List the saved base configuration files that will not be merged.
  • List configuration files that will be merged.
  • Verify fileset version consistency.
  • Create a list of all filesets installed, to be used by the post_migration command.
  • Check the size and location of the boot logical volume.
  • Check the major number for rootvg is 10.
  • Check for the missing DB directory for the fileset.
  • Determine if Kerberos is being used.
  • Check disk and memory sizes.
  • Check the firmware level for the IBM® Power Systems 7025/7026 systems.
    Note: You can obtain the required version of the firmware from the following Web site, by selecting your product: Refer to the history section of the firmware level for the statement of AIX Version 7.2 support.
  • Check whether a standby BOS on the system (as created by the multibos command) exists, and if so, it must be removed.
  • Check whether the standby BOS has the naming convention of hd* for the logical volumes. If yes, the standby BOS will be the group of logical volumes that must be migrated, unless it is removed.
  • Check that the level of AIX in the disk control block matches the version and release on the system. If not, the command prompts for appropriate actions.
  • If the bos_hd5 logical volume is the boot logical volume, check whether the bos_hd4 and bos_hd2 logical volumes exist.
  • If you are migrating from an earlier version of AIX, verify that the correct updates are applied.
  • Verify system platform.
    Note: If the platform is not supported for AIX Version 7.2, a minimal pre-migration check is performed since the system might be used for a mksysb migration.
  • Print a recommendation that a system backup be made before the migration.

The output from the post_migration command is saved in the /home/post_migration date directory.

The post_migration command performs the following actions:
  • Verify fileset version consistency.
  • Check the installation list from before the migration, and inform the user of any filesets that might still need migrating.
  • Compare saved and merged configuration scripts and save the differences.