BDF not displaying a disk

[Mark Brook]

We have a test system that used to work fine.
Until the other day (susprise).

The problem is data seems to have gone from one of the disks.
When you do a BDF the disk isn't displayed, however you can cd to that disk, also move/copy etc files into that disk. I've looked at the fstab file and the disk is mentioned ie
/dev/vg12/disk12 /disk12 vxfs rw,suid,delaylog,datainlog 0 2

Does anybody have any idea?

Thanks

Mark

[James R. Ferguson · Accepted solution]

Hi Mark:

Does this report the device file?

# vgdisplay -v | grep /dev/vg12/disk12

Also, does this show the device file?

# cat /etc/mnttab

Regards!

...JRF...

[steven Burgess_2]

Hi Mark

Try mount -a

Any errors

Steve

[S.K. Chan]

Your /etc/mnttab file is probably corrupted. Do this ..
# cd /etc
# rm mnttab
# /etc/mount -a
# bdf
Does it now appear in "bdf" output ? Another possible explanation to this is /disk12 is located in the root (/) filesystem. To test ..
# mkdir /test
# mount /dev/vg12/disk12 /test

[Anil C. Sedha]

Mark,

Since you are not able to view the mounted disk volume name in your bdf, i believe there is a mount problem of the disk.

Try mounting as suggested last here, as

mount -a

If you still do not see the disk, do a
vgdisplay -v /dev/vg12

This will give you the disk names at the bottom. Check if your disk name is listed. If it is there do a

pvdisplay -v /dev/dsk/c1t0d0 (disk number)

If you get results here, there is no problem with your disk.

add this entry in place of your current fstab entry for the disk.

/dev/vg12/disk12 /disk12 vxfs rw,suid,nolargefiles,delaylog,datainlog 0 2

Then mount again using
mount -a

You should not get any error after mount command and should be able to see it. Else display your mount error.

Hope this helps.

Regards,
Anil

[Mark Brook]

This might seem a silly question, but what does mount -a do?

Do I have to type mount -a disk12 ?

[Mark Brook]

This might seem a silly question, but what does mount -a do?

Do I have to type mount -a disk12 ?

Also the disk is not mentioned in the mnttab.

[James R. Ferguson]

Mark:

'mount -a' causes all filesystems defined in 'etc/fstab' to attempt to be mounted. If they are already mounted, that's so noted. If they cannot be mounted, (e.g. because of illegal options), then that is so noted.

Regards!

...JRF...

[S.K. Chan]

I did a quick experiment by editting /etc/mnttab (you're not suppose to edit this file btw), deleting an entry in it and afetrwards running "bdf". Sure enough that "deleted entry" does not show up in "bdf" output. Running "mount -a" will rebuild /etc/mnttab.

[Mark Brook]

When i do mount -a i get the following

vxfs mount: /dev/vg12/disk12 no such device


Then when I do vgdisplay -v /dev/vg12

vgdisplay: Volume group not activated.
vgdisplay: Cannot display volume group "/dev/vg12".

[S.K. Chan]

Ah..something might be wrong with vg12 then. Try to activate it ..
# vgchange -a y /dev/vg12
Do you see any error ? So it looks like my 2nd guess is right .. you are not accessing /dev/vg12/disk12 mounted on /disk12 as you might thought. The current /disk12 is residing on the root filesystem.

[James R. Ferguson]

Hi Mark:

You can't mount a filesystem to a logical volume in an inactive volume group. To activiate the volume group do:

# vgchange -a y /dev/vg12

Then do:

# mount -a

Based on you original post, you will probably find your copied/moved files in the '/disk12' directory in the *root* mountpoint ('/').

These files will *disappear* if/when you successfully mount '/disk12'

Regards!

...JRF...

[Mark Brook]

Maybe I'm just been too carefull, but when I do the vgchange and it comes back fine, will all files on that be lost still?

Thanks again

Mark

[James R. Ferguson]

Hi (again) Mark:

No, the files wou't be permanently lost, just invisible. When you mount /disk12, the files that are currently in root's mountpoint in the directory /disk12 will not be visible. To expose them, unmount /disk12.

Regards!

...JRF...

[Sandip Ghosh]

Better, copy the existing file of present /disk12 to someother directory, do a vgchange on vg12, mount /dev/vg12/disk12 on /disk12 and then copy those files on the mounted directory.

Sandip

[Martin Johnson]

You may what to do a tar of /disk12 before you mount /dev/vg12/disk12. Delete the files in /disk12 (to recover the space). Mount the disk and untar the files. This effectively moves the files from the / file system to the /dev/vg12/disk12 file system.

HTH
Marty

[Mark Brook]

just done the vgchange but get the following.



y # vgchange -a y /dev/vg12
vgchange: Warning: Couldn't attach to the volume group physical volume "/dev/dsk
/c3t14d0":
The path of the physical volume refers to a device that does not
exist, or is not configured into the kernel.
vgchange: Warning: couldn't query physical volume "/dev/dsk/c3t14d0":
The specified path does not correspond to physical volume attached to
this volume group
vgchange: Warning: couldn't query all of the physical volumes.
vgchange: Couldn't activate volume group "/dev/vg12":
Quorum not present, or some physical volume(s) are missing.

[S.K. Chan]

That means c3t14d0 which is suppose to be in vg12 is not responding ( a possible dead disk ). As a result the volume group cannot be activated. This has to be a 2 disks volume group right, otherwise it would not complain about not meeting the quorum requirement. Try bypassing the quorum in the activation ..
# vgchange -a y -q n /dev/vg12
Does that work ?

[Telia BackOffice]

do an :
ioscan -fnC disk
to see the status of the disk. The disk is the one you found with:

vgdisplay

BR,
Jannik