HSM and XIV data movement

[rallingham]

I have a customer that has a DS5000 disk and they will be migrating their data to a XIV. One of the partitions that will be migrated is from a UNIX box and that partition contains HSM Stub Files. I have no idea how this data migration happens but it seems to me that if the data is migrated from one partition to another partition, even if the directory retains the same name (if that is possible) this would initiate a RECALL of all the HSM data (about 14 TB) to a small 500 GIG file space.
Am I correct in this assumption or is the data migration from one array to an XIV transparent? This thing has me a little concerned.
I know that you cannot move HSM data to a different place without recall but is this really a move data?

 

[rallingham]

Any one got anything to offer on this?

 

[moon-buddy]

You may be able to eliminate a "re-stub" of the HSM files. If you have SVC, try setting up a mirror of the DS5000 disk with the new disk in XIV. The mirror should also be seen by TSM.

I have not tried this but I think this should work.

 

[rallingham]

Thanks for the advice. I will pass this by our config guy and see what he has to say. Sounds like it should work.
The 5000 is being retired so they have to get off the unit.

 

[prosham]

The UNIX volume would be moved transparently by XIV migration tool - the contents and "location" will be identical from the point of view of the HSM data, only the paths and Fibre Channel WWN would bedifferent, this is not visible at the HSM software layer.

 

[Jafco]

I have 2 servers with filesystems managed by hsm. The original disk was on a ds4800 and new on the xiv. I assigned a new disk from the xiv then ran extendvg to add to the vg. Then run migratepv to move from the old hdisk to the new one. When that is done run reduce vg to get rid of the old hdisk.

 

[rallingham]

The data did migrate over, more or less, ok but the customer ignored my warnings regarding the HSM daemons. They left them up and running and this caused just under10K files to become corrupt for some reason. It is not as transparent as you think. Of course now I have more work as I have to recover the directories and the stub files that are listed as corrupt.