weird things when mirroed disk went bad! Pls help...

[chamberlian]

One vpar has a mirrored root disk. The mirroed one went bad. lvreduce removed the mirroed copy of lv. pvdisplay show no lv on this pv anymore. When I run vgreduce, I got an error said there was an lvol20 on that pv. while lvdisplay /dev/vg00/lvol20 told that there is no such lv exist, neither did the lvmtab has this lv. mv /etc/lvmtab /etc/lvmtab.bak and vgscan -a -f, create a new lvmtab, strings /etc/lvmtab all i can see is blank.
that's pretty weird. At last , I brought server to maintenance mode and vgexport vg00 with a map, then vgimport vg00 on root disk. shutdown and replace disk, and did mirror copy stuff. But strings /etc/lvmtab show three pv exist in vg00, while there are only two pv available. How is that happene?

Thanks in advance!

[Devender Khatana]

Hi,

This happened as you did not informed system before removing the disk. You did the mirror copy stuff again rather then using vgcfgrestore. You can use

#vgreduce -f

to forcely remove the missing PV's from the VG.

HTH,
Devender

[chamberlian]

3Q very muchï¼ Devenderï¼

I will give that a tryï¼
but how did the ghost lv exist at the very first and prevented me from reduce pv from vg00?

[Devender Khatana]

Hi,

There is nothing like ghost LV. It was the one which was created somethime and was not mirrored to the second disk. Quite possible that it could not have been even not used anytime. You can use your pre-failure configs to verify this.( something like old nickel outputs)

I am leaving for the day and shall be back till evening so the responses may be delayed if required. But their are others to help you since then.

Regards,
Devender

[Sameer_Nirmal]

Did youreboot the system when the disk failed? When you did use lvreduce Did you use lvreduce for lvol20?
Pls give the exact step you followed to understand what could have gone wrong to have this peculier problem.

Did you succeed by vgreduce -f vg00 ?
Can you put on output vgdisplay -v vg00 , strings /etc/lvmtab lvdisplay -v /dev/vg00/lvol20