what to do if the private region of a particular disk group is full?

[YaseenMubarak]

what to do if the private region of a particular disk group is full? What are the design considerations for the size of private region in Vxvm disk group?

[Gaurav_S]

Hello

Well that is a tough situation, usually it happens on older versions of SF like 4.0 or 3.5 where private region use to be pretty small like 4MB or 8MB ... in such cases if number of objects are grown into a diskgroup, you may run out of private region space...

Now a days in 5.x version you would have 32MB+ space reserved for private region which can store considerably store very high number of objects ...

The quickest solution I would think of would be to split the diskgroup but that needs an DGSJ (diskgroup split & join license) , do u have DGSJ license ?  you can confirm that from "vxlicrep -e |grep -i dgsj"

There is no online growing of private region at this point, can u tell what version of vxvm you are using at this stage ?

G

[mikebounds]

I would think (theory / not tested) you could add a new disk with a big private region to disk group, mirror (or do subdisk move) volumes on an existing (small private region) to new disk and then remove old disk.

If you have lots of disks, then once you have removed first "small private region" disk, you can reformat with big private region and then repeat process.  So you would just need just 1 (temporary) disk to do this.

Mike

[TonyGriffiths · Accepted solution]

Hi

Just to add to Mike and Gaurav's repsonses.

Long long ago, the private region size was ~ 1MB and I did experience a handful of instances where it had been exhausted. The private region contains a number of internal structures one of which is the configDB. The config DB is a store of all the objects in the diskgroup. Each volume, plex subdisk is a record in this database (~256bytes each). If you happen to create so many objects that you exhaust the free space, you will not be able to create any more obejcts. The DG should be fully usable etc.

The good news is that over the years we have increased this region such that the latest version 5.x (possibly 4.x) have a ~32MB region which is a magnitude larger than the old size and will store a very very large number number of objects.

Hence I havent bumped into this for a long long time :)

On a side note, the region is cyclinder aligned so is approx 32Mb but could be bigger depending on your geometries etc.

cheers

tony