Strict mirroring when deactivating contiguous policy

[Anders Blomkvist]

We need to increase the size of some filesystems (/var and /opt). In order to do this, I have to disable the contiguous policy for the extent allocation. My plan is to unmirror, disable contiguous, extend submit, remirror. Do I have to disable the strict mirroring policy as well (vg00 consists of two disks -> one mirror) in order for this resize to work?

[Fred Ruffet]

I believe /var should be contiguous, so you can only increase it using a recovery tape.

Also, why do you want to break mirror to increase size ?

Regards,

Fred

[Mohanasundaram_1]

Hi,

/var and /opt need not be contigous. If you have online JFS installed, these 2 can be extended online.

If not, you have to boot the system in single user mode and extend them. Have you tried this and facing some problem? if so, provide details of what problems you encountered.
Strict mirroring policy is to ensure that you do not mirror any LV onto the same PV. You need not modify this policy when you are extending /var and /opt.


With regards,
Mohan.

[Anders Blomkvist]

We have onlineJFS installed so I can extend online by disabling contiguous. I know what the strict policy mean but I need to know if it has to be disabled when extending the filesystems online because if strict has to be disabled as well as contiguous, then we will have to use a recovery tape as we require the strict policy to be enabled.

[Mohanasundaram_1]

Ok,

As I said, you need not modify any of the policies when you are extending.

In fact, ensure that you have enough space on the mirrored disk for the new extension so those extents will also be mirrored. You do not have to break the mirror and then remirror after extending.

With regards,
Mohan.

[Anders Blomkvist]

well you're wrong there. I've already tried increasing the filesystem online but lvextend fails because the contiguous policy is set so I do need to disable that. The question is if I also have to disable the strict policy which I do not want to do.

[Florian Heigl (new acc) · Accepted solution]

You do not have to disable the strict allocation policy, unless the distribution across Your PVs is not okay.


--- Physical volumes ---
PV Name /dev/dsk/c0t0d0
PV Status available
Total PE 4374
Free PE 3181
Autoswitch On

PV Name /dev/dsk/c1t0d0
PV Status available
Total PE 4374
Free PE 3181
Autoswitch On


If the FreePE Values are identical, You should have no problem at all.

Also there's no reason to break the mirror.