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AutoRaid Adding Disk Increasing Capacity

Occasional Visitor

AutoRaid Adding Disk Increasing Capacity

I have an autoraid (A3515A) on a HP9000 D200. When the system was set up the
autoraid had 4-2GB drives installed. The config is now vg01/lvol1 for the
autoraid. I maxed the box out with 8 more 2GB drives. I want to increase the
size of vg01/lvol1 to include these drives. Can anyone help. Thanks ahead of
Regular Advisor

Re: AutoRaid Adding Disk Increasing Capacity

The problem here is a little thing called MaxPE per PV.
Unless specified when a VG is created (with the -e option), the default is 4G
or the largest disk in the VG (whichever is greater). This means that if you
try to add a disk to the same VG later, you will be limited to using no more
than this much space, no matter how big the disk is.

The MaxPE/PV limit is designed to prevent wasting a lot of disk space with
overhead structures that will never be used. Unfortunately, it cannot be
increased once the VG is created. To fully utilize 8G disks in a VG stuck at
4G, you have to recreate the VG, including the 8G disks from the beginning.

In the case of an autoraid though, the size of the physical disks is
irrelevant. It's the size of the LUNs that matters. If your VG was created with
2G LUNs, then it would still be limited to 4G MaxPE/PV; i.e. 4G LUNs. To use
larger ones in that VG, it must be recreated.

Since this is not your root VG, you should be able to create a new VG (say
VGtemp), copy all the data from VG01 to it, then export both VGs (using SAM).
Finally, import the VGtemp as VG01 and you're set (again through SAM).