Veritas LVM Data Migration(Any OS)

There are many validations that need to be done before executing the below steps/commands such as target disk compatibility with the server/server load/all target disks have the fully redundant paths/MPIO is configured as per current vendor best practice etc.

Our preferred way of doing any data migration from one set of disks to another is to mirror the disks and then break the mirror. We use vxassist mirror to achieve this on servers using Veritas volume manager. There are other ways to migrate the data such as vxevac which can be used in certain cases. There are many other options that may be applicable for your environment. We can help identify best suited one for you and automate your migrations and fast track the project. Email us at intro@yarisolutions.com to find out how.

1. Data migration using vxassist mirror :

   1. Identify the Disk groups you would like to migrate

   2. Identify each LV per DG

   3. Identify the source disks in use per LV and volume size using vxprint -htg dg-name

   4. Ask storage admins to allocate new disks for migration. Allocated space should be larger than the lv size

   5. Map the allocated storage for each vg/lv.

   6. Add the tgt-disks to the DG using vxdg -g dg-name tgt-disk

   7. use vxassist -g dg-name mirror vol-name tgt-disk (This creates a new plex and mirrors the src plex to the new.)

   8. Check the mirror status using vxtask -l list

   9. Wait for copy to finish. Once 100% copy is done.

   10. Break the mirror using vxplex -g dg-name -o rm dis src-plexname

   11. Remove the src-disks from dg using vxdg -g dg-name src-disk command

   12. Repeat the process for each dg/lv in the system that you are looking to migrate.

   13. Delete the devices from veritas using vxdisk rm src-disk

   14. Ask storage admins to reclaim the source disks.

   15. Clean up the server of all the dead paths/disks after reclaim if any.

2. vxevac high level migration procedure :

   1. Identify the volume groups you would like to migrate

   2. Identify source disks per DG using vxprint -htg dg-name

   3. Identify all the disks in use for each DG and request for the tgt-disks that are 1G larger than the src-disk.

   4. Once storage has been allocated rescan for new disks

   5. Identify and map which target disks were allocated for which DG.

   6. initialize the target disks using vxdisk command

   7. Add the target disks to DG using vxdg command

   8. use vxevac -g dg-name src-disk tgt-disk

   9. Check the status using vxtask -l list. Once copy finishes

   10. vxdg -g dg-name rmdisk src-disk

   11. Repeat steps 8, 9 and 10 for each source disks in DG.

   12. Repeat steps 5 through 11 for each DG

   13. Ask storage admin to reclaim all the migrated disks

   14. Clean up the server of all the dead paths/disks after reclaim.