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I'm running Ubuntu Server 14.04 on a system with 2 physical disk drives. I am frequently seeing mount errors on startup. When I check the drive partitions using GPARTED, I see that my two "non-system created" data partitions have the wrong disk assignments (i.e. sda1 vs sdb1) or visa-versa. If I hand edit /etc/fstab to match GPARTED, the system will boot error free one time. On the second restart I will get the "serious mount problem" error for the 2 data partitions and when I check GPARTED, the disk assignments have changed again (again, GPARTED and fstab don't match).

A listing of my /etc/fstab is:

/etc/fstab: static file system information.


Use 'blkid' to print the universally unique identifier for a

device; this may be used with UUID= as a more robust way to name devices

that works even if disks are added and removed. See fstab(5).


/ was on /dev/sdb2 during installation

UUID=766a06a4-e5af-484a-adf0-fa1e88da7212 / ext4 errors=remount-ro,user_xattr,acl,barrier=1 0 1

swap was on /dev/sda6 during installation

UUID=8c42f835-ead3-43fb-88d8-196f5dfc3aa7 none swap sw 0 0

swap was on /dev/sdb3 during installation

UUID=2214deec-ba98-47da-aea7-4e46998f3e57 none swap sw 0 0 /dev/fd0 /media/floppy0 auto rw,user,noauto,exec,utf8 0 0 /dev/sda1 /media/ken/Linux-Data ext3 defaults 0 2 /dev/sda5 /media/ken/Data2 ext4 defaults 0 2

The device designations in the last 2 lines are the ones in question. The fstab entries to NOT change between system restarts but the mount points in the GPARTED display do.

Does anyone have a fix for this?


Mr. Young and Mr Gedak,

Following is my fstab file and two blkid outputs. The fstab output is correct.

The first blkid output was after a reboot and is WRONG! The sda and sdb device partition data is reversed. The 2nd blkid output was after a second reboot (fstab not changed). It shows the sda and adb partition data CORRECTLY.

I didn't see any duplicate UUIDs.

Does anyone have any idea why the GPARTED and blkid outputs alternate on consecutive reboots? The alternating partition data is real since when the partition assignments are reversed, the boot sequence halts with disk mounting errers (I have to press "s" to skip the mounts).

Thanks again.


I copied the contents of a text file showing my fstab and 2 blkid outputs. The text file contents show up in the text entry box but does not appear in the main body of the question. Is there a way I can attach the text file or edit this question so that the text is displayed for question viewers?

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Please Quote your /etc/fstab, reboot, run blkid twice, once when the system is booted the way you want and once when it isn't and post the blkid results here. –  eyoung100 Jun 2 '14 at 17:04
Also check to ensure that none of the partitions have duplicate UUIDs. Duplicate UUIDs can occur if a partition was copied. You can list UUIDs using the blkid command. Duplicate UUIDs can cause problems when mounting. To fix, one of the duplicates will need a new UUID set. This can be done with newer versions of GParted (e.g., 0.18.0). –  Curtis Gedak Jun 2 '14 at 18:32
Use UUID not device to mount your data partitions. Drive order is determined by BIOS, and if drives spin up at different speeds drive order may not be consistent. That is now why UUID is preferred. Or you can use labels as a mount if you have labeled your data partitions. –  oldfred Jun 6 '14 at 16:17

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