Cannot Remount Drive After Lost ISCSI Connection

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Hi all,

We’ve having an issue at the moment where an iSCSI connection was temporarily lost on a few VMs running CentOS 6 on ESXi.

The problem is, now that the iSCSI connection has returned, we are not able to remount the drive.

At first the drive is read-only, so I tried ‘*mount -o remount,rw*’ which didn’t work (still read-only), so then I tried a ‘*umount*’ (which worked), but now I get the following error when trying to mount it again:

root@server [~]# mount /backup/
mount: /dev/sdb1 already mounted or /backup busy root@server [~]# mount /dev/sdb1
mount: /dev/sdb1 already mounted or /backup busy

I have also tried ‘*echo “- – -” > /sys/class/scsi_host/host1/scan*’ and checked to see if any processes were using /dev/sdb1 or /backup using ‘
*fuser*’ and ‘*lsof*’.

I know a reboot will solve it, but I’m trying to avoid that as best I can, so I’m wondering if anyone else has any other ideas?

Any help would be greatly appreciated, thanks. :)

Regards,

Kyle Thorne

3 thoughts on - Cannot Remount Drive After Lost ISCSI Connection

  • Any clue on dmesg? I’d remove de disk and rescan…

    El jue., 5 de marzo de 2015 a las 7:40, Kyle Thorne (< kthorne@staff.ventraip.com>) escribi

  • The most recent message is:

    [3108269.919256] sd 2:0:1:0: timing out command, waited 1080s
    [3108269.919528] sd 2:0:1:0: [sdb] Unhandled error code
    [3108269.919535] sd 2:0:1:0: [sdb] Result: hostbyte=DID_OK
    driverbyte=DRIVER_OK
    [3108269.919540] sd 2:0:1:0: [sdb] CDB: Read(10): 28 00 00 01 21 47 00 00
    08 00
    [3108269.919586] EXT4-fs error (device sdb1): ext4_find_entry: reading directory #2 offset 0

    Removing the device, rescanning, and then re-adding it worked, but that moved the device to /dev/sdc instead. Which is fine, but it would be much better if it was /dev/sdb.

    Thanks for your help. :)

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  • Hi,

    I have had the same problem and I solved it with following commands :

    iscsiadm -m node -o show (not sure this was useful)
    iscsiadm -m node –login iscsiadm -m session -o show

    after, umount -f and mount each mountpoint and now I can show disks with command blkid.

    Hope will help. Laurent