SCSI errors

[admin1979]

Hello,

We have SLES 10 System with SCSI disks.
We have noticed attached errors occurred for lets say 5 minutes. Wonder if the disk is going to fail?
If yes what are the best possible ways to minimise the imapct? I have already taken the backup of the partitions like,
/
/boot
/opt
/var
/var/home
/srv/fpt etc..

Please suggest.


Thanx,
Admin

[Ivan Ferreira]

SCSI disks are able to self handle bad blocks. but yes, there is the possibility that the disk is about to fail.

Probably would be better if you replace the disk before disaster strikes.

Take a good backup and restore to the new disk. From your output, I cannot say what is the file system associated with your disk.

The following information is also needed:

fdisk -l
cat /etc/fstab
vgdisplay -v

[admin1979]

Here is the required data.
sda is the boot disk :(

Thanx,
admin

[Vitaly Karasik_1]

I'll suggest to run something like

dd if=/dev/sda of=/dev/null


for read whole disk and see how many errors you'll see.

[admin1979]

Ok that can be one check. But now that we already know that there is a problem in this disk. More important thing is to make sure that there is a minimal damage if the disk is going to go down.

We have taken the backup of the root partitions. But still we also would
like to prepare a disk which in case of the failure can be inserted and bring up the system as it was before.
Is there any such efficient way to do it?

We have a new disk of similar size.
So any suggestions?


Thanx,
admin

[Vitaly Karasik_1]

What is sda disk - it it physical disk or hardware mirror of 2 physical disks?

In second case you should break mirror, replace disk and re-build RAID - all using REIAd manager.

In the first case, if you have the same size or bigger disk and free SCSI slot in your server, I'll just insert new disk and clone old -> new disk using "dd".

[admin1979]

Hi,

Its a single disk without RAID. So lets suppose I insert a new disk in the slot and run

dd if=/dev/sda of=/dev/sdd bs=1M

Will work?

Will this disk boot as the original as well?


Thanks,
admin

[Vitaly Karasik_1]

Yes, this should work.

[Steven E. Protter]

Shalom,

You could also use software raid tools mdadm

http://tldp.org/HOWTO/Software-RAID-HOWTO-5.html#ss5.6

SEP

[admin1979]

mdadm look great. But since never tried before , trying out on a production system directly , is bit of hesitation.
Cold you please clarify the steps involved?


Thanx,
admin