Performing an alternate disk migration installation
Alternate disk migration installation allows you to create a copy of rootvg to a free disk, or disks, and simultaneously migrate it through Network Installation Management (NIM) to a new release level.
- Reduced downtime; the migration is performed while the system is up normally, and there is no need to boot from any media.
- Quick recovery in case of migration failure.
- High degree of flexibility and customization.
Reduced downtime. The migration is performed while the system is up and functioning. There is no requirement to boot from install media, and the majority of processing occurs on the NIM master.
Quick recovery in the event of migration failure. Because you are creating a copy of rootvg, all changes are performed to the copy (altinst_rootvg). In the event of serious migration installation failure, the failed migration is cleaned up, and there is no need for the administrator to take further action. In the event of a problem with the new (migrated) level of AIX®, the system can be quickly returned to the premigration operating system by booting from the original disk.
High degree of flexibility and customization in the migration process. This is done with the use of optional NIM customization resources including image_data, bosinst_data, exclude_files, premigration script, installp_bundle, and post-migration script.
Network Install Manager Alternate Disk Migration (nimadm) is a utility that allows you to do the following:
- Create a copy of rootvg to a free disk, or disks, and simultaneously migrate it to a new version or release level of AIX.
- Using a copy of rootvg, create a new nim mksysb resource that has been migrated to a new version or release level of AIX.
- Using a nim mksysb resource, create a new nim mksysb resource that has been migrated to a new version or release level of AIX.
- Using a nim mksysb resource, restore to a free disk, or disks, simultaneously migrating it to a new version or release level of AIX.
For more information about the nimadm command, refer to the Commands Reference.