This document discusses the procedures specific to the "rootvg" volume group on how to migrate the contents on one physical volume to another physical volume in the same volume group.
This document applies to all levels of AIX Version 4.
WARNING: Please do not use this document if the system is a /usr client, diskless client, or dataless client.
IBM documentation can also be found online at the following URL:
http://www.rs6000.ibm.com/resource
The command to move data from one physical volume to another physical volume within the same volume group is called migratepv. The usage parameters for this command are as follows:
migratepv [-i] [-l LVname] SourcePV DestinationPV...Note that more than one destination physical volume can be specified.
The first steps are to identify what disk you want to migrate and what disks to which you want to migrate it. First, you can only migrate to disks that are already in the rootvg volume group. To get a list of disks that are already in the rootvg volume group, run the command lsvg -p rootvg.
Example:
# lsvg -p rootvg rootvg: PV_NAME PV STATE TOTAL PPs FREE PPs FREE DISTRIBUTION hdisk0 active 515 116 57..00..00..00..59 hdisk1 active 515 515 00..00..00..00..00Now, determine the space that is currently being used on the disk you wish to migrate. This will be the TOTAL PPs value minus the FREE PPs value for the desired disk. In the preceding example, choose hdisk0, which is using (515 - 116) PPs or 399 physical partitions.
You would then need to find a disk or disks that have the available space. In this case, hdisk1 has 515 free physical partitions, which is more than the require space of 399 physical paritions and will fulfill our needs.
The only situation that is specific to rootvg is if the desired disk contains the boot image. Generally, this will be the Logical Volume called hd5 and will have a Type of "boot", as shown from a partial list of lsvg -l rootvg:
LV NAME TYPE LPs PPs PVs LV STATE MOUNT POINT hd5 boot 1 1 1 closed/syncd N/ATo determine if the boot image is on the disk you wish to migrate, run the lslv -l <bootlvname> command.
Example:
# lslv -l hd5 hd5:N/A PV COPIES IN BAND DISTRIBUTION hdisk0 001:000:000 100% 001:000:000:000:000In this case, the boot image resides on the disk we wish to migrate. The boot image will need to be moved first. Do so with the command migratepv -l <bootimage name> <source disk> <destination disk>.
Example:
#migratepv -l hd5 hdisk0 hdisk1NOTE: The destination disk must be supported as a boot disk. If the machine is running AIX 4.1, run the command bootinfo -B hdisk# to determine if the disk is supported as a boot disk. If the command returns "1", then it is supported as a boot disk. AIX 4.2 and above will present a warning from the migratepv command if the destination disk is not bootable.
After the boot image has been moved, the boot record on the original disk should be cleared to prevent possible problems if the machine accidentally attempted to boot from this disk. Use the mkboot -c -d /dev/hdisk# command on the source disk to clear the boot record.
Example:
#mkboot -c -d /dev/hdisk0Afterward, update the boot image on the new destination disk. Run bosboot -a -d /dev/hdisk# for the destination disk to rebuild the boot image and generate a new boot record on the source disk.
Example:
#bosboot -a -d /dev/hdisk1At this point, you can migrate the rest of the contents of the source physical volume to the destination disk or disks.
Example:
#migratepv hdisk0 hdisk1Once this command has completed, the migration will be complete.
APAR DESCRIPTION AIX LEVEL
IX61186 BOSBOOT DOESN'T WORK ON A BLV MIRROR V4.1
IX74042 MIGRATEPV NEEDS TO MIGRATE MIRRORS V4.1
OFF OF DEAD DISKS
IX76351 BOSBOOT DOESN'T VALIDATE DEVICE V4.1
CORRECTLY
IX62417 BOSBOOT DOESN'T WORK ON A BLV MIRROR V4.2
IX68140 MIGRATEPV, MIRRORVG, AND UNMIRRORVG V4.2
NEED TO HANDLE BLV CASES
IX74905 BOOT RAM FILESYSTEM IS TOO SMALL V4.2
IX74041 MIGRATEPV NEEDS TO MIGRATE MIRRORS V4.2
OFF OF DEAD DISKS
IX66626 BOSBOOT DOESN'T VALIDATE DEVICE V4.2
CORRECTLY
IX73591 MIGRATEPV NEEDS TO MIGRATE MIRRORS V4.3
OFF OF DEAD DISKS