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I'm running Ubuntu 11.04 (no dual boot) and tried installed secondary 3TB Seagate SATA disk. I used GParted to partition the disk into a 2.0TB partition and a 800odd GB partition (remainder) and managed to manually mount both /dev/sdb1 and /dev/sdb2.

Then I added entries to fstab for automount but Ubuntu won't start after a reboot, unless I physically disconnect the disk, which allows me to start Ubuntu with option to skip mounting /dev/sdb1 and /dev/sdb2.

As soon as I connect the disk and reboot computer freezes, I can't get GRUB menu, system settings, or boot menu. If I revert to original fstab without new partitions and connect the disk it makes no difference, still freezes on reboot.

This is a new disk with no data so happy to format disk and try again but can't get that far.

NOTE: before partitioning I managed to mount successfully with fstab but mounted partition was only about 750GB when capacity shows 3TB so formatted disk and partitioned.

fstab looks like this at the moment:

# /etc/fstab: static file system information.
# Use 'blkid -o value -s UUID' 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).
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc nodev,noexec,nosuid 0 0
# / was on /dev/sda1 during installation
UUID=b8a0bf10-011a-43b0-b5d4-3300f75d79b6 / ext4 errors=remount-ro 0 1
# swap was on /dev/sda5 during installation
UUID=63a1fa2c-a6df-4c88-b85a-96ecdffe528f none swap sw 0 0
# auto mount /dev/sdb1 -> 3T internal disk -> 2TB partition
/dev/sdb1   /mnt/T3 vfat    rw,uid=1000,gid=1000    0   0
# auto mount /dev/sdb2 -> 3T internal disk -> 800GB partition
/dev/sdb2   /mnt/T4 vfat    rw,uid=1000,gid=1000    0   0
share|improve this question

Use the UUID values instead of /dev/sdb1 and dev/sdb2 in /etc/fstab, just as the automatically generated entries above do.

To find the correct UUIDs, do

$ ls -l /dev/disk/by-uuid/
total 0
lrwxrwxrwx 1 root root 10 mar 20 10:06 183a7e4b-0a77-41e3-b4a8-9341694dc5dc -> ../../sde1
lrwxrwxrwx 1 root root 10 jan  6 21:30 21dce342-e58f-4ae3-8f6b-c95f730ada08 -> ../../sdc1
lrwxrwxrwx 1 root root 10 jan  6 21:30 3b603520-3a41-485d-80fc-671a5ba105e1 -> ../../sda3
lrwxrwxrwx 1 root root 10 jan  6 21:30 48db0710-c551-42d9-8198-7afcecbe2b4a -> ../../sda2
lrwxrwxrwx 1 root root 10 jan  6 21:30 9ab58dcd-1100-49ea-a547-a90ad1510c40 -> ../../sdd1
lrwxrwxrwx 1 root root 10 mar 20 10:06 9c9579c9-c030-4ba8-beda-d19d1d994512 -> ../../sdf1
lrwxrwxrwx 1 root root 10 jan  6 21:30 cac8b7a6-daf5-41b7-8047-171b752497e2 -> ../../sdb1
lrwxrwxrwx 1 root root 10 jan  6 21:30 d400650d-d2ff-4c37-a4b5-1e4c988a62bc -> ../../sda1

This was on my system, and shows that UUID 183a7e4b-0a77-41e3-b4a8-9341694dc5dc points to what is currently /dev/sde1 and so on. Equivalently you can run /sbin/blkid to get a list of these identifiers.

UUIDs are unique for a certain partition and do not change on reordering of disk connections, such as insertion/removal of physical devices, which makes them a more robust identifier in /etc/fstab.

share|improve this answer
ja thanks, gonna put the UUID change in when I get the partitions working. However when I remove the /dev/sdb1 and /deb/sdb2 entries from the fstab I still cant boot with the new disk connected. – Chris Apr 21 '13 at 14:19

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