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Re: ** Strange Mounting Problem **

 
Michael Gretton
Frequent Advisor

** Strange Mounting Problem **

BACKGROUND:

I have a mount point called /u02. It has an entry in fstab as follows:

/dev/vg02/lvol10 /u02 hfs rw,suid 0 2

The system boots up fine and doesn't report any problems with the disk. BTW here is an ioscan result of the drive:

disk 1 10/0.4.0 sdisk CLAIMED DEVICE HP C2490WD
/dev/dsk/c0t4d0 /dev/rdsk/c0t4d0

PROBLEM:

My dba came to me and told me that she can't start the oracle instance. After investigating a bit it appeared that all the stuff in /u02 was gone! My first thought was that someone wiped out the directory; however, as I look more closely it seems that the mount point might not be mounted properly or at all. I try to do a umount /u02 but that doesn't work because the system reports that there is no entry for /u02 in mnttab which tells me it never mounted. When I do an fuser - I see no one using it and no processes. When I try to do a mount it won't let me because it says the device is busy. I can do lvdisplays and vgdisplays and see that everything is available.

Please help. If you need more background info, I can provide that. I am really confused....and nervous...

Mike
14 REPLIES 14
James R. Ferguson
Acclaimed Contributor

Re: ** Strange Mounting Problem **

Hi Michael:

Try this:

# mv /etc/mnttab /etc/mnttab.old
# mount -a

If /etc/mnttab is corrupted, then this will create a new copy.

...JRF...
Joseph C. Denman
Honored Contributor

Re: ** Strange Mounting Problem **

Hi Mike,

When you do a bdf, do you see u02?

If not, have you tried running fsck on the file system?

...jcd...
If I had only read the instructions first??
neylan tokerler
Occasional Advisor

Re: ** Strange Mounting Problem **

hi,
is there quite large difference btw du -sk "file_sytem_mount_point" and bdf? if you manage to see it in bdf of course.
If there is an abnormal difference, and you cannot umount the fs, (removing mnttab), then what you can: reboot into single user mode, then none of the fs's will be mounted, and try:
cd /u.. , ll, those you see there should not be there at all. so remove them and mount the fs. hope this is relevant.
this will mean, your mount point was not a mount point anymore, but a directory under /.
good luck.
neylan
John Palmer
Honored Contributor

Re: ** Strange Mounting Problem **

Device busy could mean that the mountpoint is busy, not the logical volume.

Run 'fuser /u02' to make sure that no-one is cd'd to /u02.

Run 'mount -a' to attempt to mount all filesystems in /etc/fstab.

Have a look in /etc/rc.log and check the output from /sbin/rc1.d/S100localmount start.

Regards,
John
Sachin Patel
Honored Contributor

Re: ** Strange Mounting Problem **

Hi Michael,
more /etc/mnttab. do you see the line for /u??.
You can vi this file and remove this line (It is not recommended but I does that). then mount -a. If doesn't work.
Bring system up on single user mode.

fsck that volume. If that doesn't work.
more /vad/adm/sbtab. find the alternet superblock and use that on fsck.
remove that mount point /u? and recreate it.


Sachin
Is photography a hobby or another way to spend $
Magdi KAMAL
Respected Contributor

Re: ** Strange Mounting Problem **

Hi Michael,

1. ask your dba to do shutdown immediate in svrmgrl ( oracle server manager ).
2.Try to find which process is using /u2, with the following command:

fuser -cu /u2

Consider only the numbers from the output, you will find user names manipulating the directory between parantheses.

kill all these processes.

3. Try to mount the /u2 :

mount /u2

Notice : Your current working directory must be somewhere outside /u2 ( otherwise you will have the message : device busy !!! ).

Hope this would helps.

Magdi
Michael Gretton
Frequent Advisor

Re: ** Strange Mounting Problem **

The suggestions that deal with seeing what space is being taken up by the mount point come to a stall because my main problem is this: The filesystem doesn't seem to be mounting at all because the mount point (or whatever ) is reporting that it is busy. What gives? I have rebooted and it still won't mount. Fuser doesn't report anyone or anything as using it.

It isn't in the mnttab because it never mounts to begin with.

Mike
Steve Post
Trusted Contributor

Re: ** Strange Mounting Problem **

ok here's some guesses: You say /u2 isn't mounted. Is there a /u2/somethingelse mounted?
Do you have any links where something is linked to /u2?
Patrick Wallek
Honored Contributor

Re: ** Strange Mounting Problem **

Can you post a copy of your /etc/fstab please? Looking at that may help us to help you.
Joe Colucci_1
Frequent Advisor

Re: ** Strange Mounting Problem **

Check that nothing else is mounting anything to the /u02 directory. For example, if you use pfs_mount to mount something to the /u02 directory, it will be mounted on top of what was previously mounted. You will not get any errors, but you will not be able to see the file system that was first mounted to the directory.

--Joe
Charles McCary
Valued Contributor

Re: ** Strange Mounting Problem **

Michael,

Please cat a copy of your /etc/fstab, and your current /etc/mnttab

Also, in order to keep interest up in solving your problem, you might want to assign points to some of the other folks who've already worked hard on your problem.

tx,
C
Owen Keane
Occasional Advisor

Re: ** Strange Mounting Problem **

I suspect there could be problems with the underlying mount point. Check that there is only one directory called /u01, and no files of the same name. Also check the contents of the mountpoint. I have seen problem like these when there is files and directories in the mountpoint.
Varghese Mathew
Trusted Contributor

Re: ** Strange Mounting Problem **

Hi,

It seems there is something fishy. We had the same problem with few of our filesystems in one of our servers recently. The problem was in the chronological order of filesystems getting mounted as specifed in the /etc/fstab file.

Assume /u01 is your original oracle filesystem.
then, you may be mounting another filesystem on the mountpoint /u01/oradata1.

Here if you try to mount /u01/oradata1 first and then try to mount /u01 then it won't allow you to do the same and will throw an error saying something like multiple mountpoints etc.

So please work around the entry of mountpoint in fstab.

Can u try mounting it manually with the mount command .., and see what error is thrown out..

Hope this helps..

cheers !!!
Mathew
Cheers !!!
Joseph C. Denman
Honored Contributor

Re: ** Strange Mounting Problem **

Have you tried booting into single user mode???

Then attempt to do maintance.

...jcd...
If I had only read the instructions first??