stale mirror

[avik]

I have two disks - diska and diskb.

I am removing the diskb, that will cause for a stale mirror error.

Now that I am presenting the same disk back thro' a different device id.

I did a vgscan, which will bring the new disk under the same vg.

Now that I wanted to start the mirror back.

Can someone explain the proceudre.

[Coolmar]

You will have to mirror each logical volume seperately.

IE: lvextend -m 1 /dev/vgxx/lvolx /fullpath/diska /newpath/diskb

Do the above for each logical volume that you want to mirror.

To verify, type lvdisplay -v /dev/vgxx/lvolx

[Peter Godron]

Hi,
a very useful manual which you will find mentioned again and again.

http://docs.hp.com/en/5991-1236/When_Good_Disks_Go_Bad.pdf

Covers most topics.

[avik]

I am sorry but my question was a bit incorrect, I wanted to ask :

The luns are presented from two different storages (EVA5000). The luns are mirrored from the host using LVM.

There was a devicepath change for the lun presented from the second storage. The earliner device path for the physical disk was /dev/dsk/c39t0d0 and the new device path is /dev/dsk/c40t0d0.


Now that the lvdisplay shows a stale status for the luns for which the device path has changed.


I tried removing the /etc/lvmtab and performed a vgscan - that brought the new disk into the same VG, obviously its still showing stale.

I also performed a vgcfgrestore to the new device which failed saying as per the /etc/lvmconf/vg.conf, the new disk doesnt belong to this vg.

I was trying to execute the below action, but the first and second step failed as the old device path is not available


lvreduce -m 0 /dev/vg01/d01 /dev/dsk/c39t0d0
vgreduce /dev/vg01 /dev/dsk/c39t0d0

Please can you explain the proceudre to remove the mirrored copy when the
old disk is not available or if its available thro' a new path.

[Steven E. Protter]

Shalom,

So long as the logical volume is not in a volume group mounted in shared mode, lvreduce will work.

lvsplit would too.

BTW, the EVA is much better at mirroring than the OS. Its better to use the disk storage unit and take this i/o and cpu expendiature off the system.

SEP