How to reduce SAN disk size

[baridban]

Hello,

Blade Server running with OpenVMS Ver 8.4 and attached with HP EVA storage.
One Application disk Total size 500GB Free space 100 GB.
Please help me how can I reduce the total size of the disk to 250 GB?

Or I have to create another disk of Total Size with 250 and restore the data from old disk?

Thanks.

[abrsvc]

You must have left out something here because it looks like you have consumed 400GB of space (500gb total -100gb free=400gb used).  This won't fit onto a 250gb drive.

Can you provide more details about what you are trying to accomplish?

Thanks,

Dan

[Hoff]

Not really sure what you're asking, so...

If your question is how to compress 400 GB of stuff into a 250 GB disk?  Donno.   It's your data.  Figure out what you don't need, and delete it.   Or compress it.   Or figure out how to split the data across multiple disks.  Not something we can really help with, without knowing more about the application(s) and disk contents involved.

Or if your question is how to change a disk size?   That's done out at the EVA controller, by changing the size of the vdisk.  Make sure you offload your data before attempting that as that'll avoid data loss, and expect to have to reload onto the newer and smaller disk.  HPE has the EVA manuals posted online, and some details can vary by the specific EVA model, firmware and storage hardware involved.

Or is your question whether BACKUP will restore the original size?   BACKUP /IMAGE doesn't care about the size of the target disk and will create the appropriate structures for the size of the target disk, and things will work fine — so long as you don't try to use it to load more than the capacity of the target disk.  BACKUP /PHYSICAL does care rather more about matching disk sizes.

Or just get more storage.  There are terabyte-sized 7200 RPM "Universal" (the Compaq and HP disk bricks with the metal fins) FATA FC disks on Amazon for ~US$223, and some 600 GB Universal FC disks for ~US$44 each.    HP SAS and SATA disks are cheap there, too.  Offload and replace some older and smaller disks, or get another shelf, if you need more capacity or more disk slots.   Or replace the whole EVA with an HPE 3PAR gizmo, as those EVA boxes are getting ancient and slow.

[baridban]

My Apologies.

It was my mistake. 

How to reduce the total size of disk from 500 GB to 250 GB.

Earlier I was mean to say free space is 400 GB.

[Hoff · Accepted solution]

Back up the contents of the disk via BACKUP /IMAGE or some other tool, delete the vdisk via the EVA console interface, and create a new vdisk of the desired size.  

Are you really looking for a pointer to the EVA manual for whichever EVA controller you have here, maybe?   (Or maybe for the HPE EVA community, given this question isn't really specific to OpenVMS?)   In any case, see the EVA Command View docs and the EVA user's guide — HPE has various command view resources and documentation available.    That'll have how to delete the vdisk, and create a new and smaller one.

Be extremely careful where you aim the EVA vdisk delete commands.

[baridban]

Thank you Hoff for your  guidance.

I just wanted to know apart from backup from VMS side I can do anything, to avoide downtime.