I've been building a live ubuntu server (10.04 LTS) to run off a thumb drive and it's nearly there. However, I've gotten stuck at one step.

I need to run update-grub but it's complaining about:

/usr/sbin/grub-probe: error: cannot find a device for / (is /dev mounted?).

My fstab file contains:

# filesystem   mount point     type    options                 dump    pass
UUID=76d2077e-9726-4f95-abab-323cb426b099       /               ext2    defaults                0       0
proc            /proc           proc    nodev,noexec,nosuid 0       0
sys             /sys            sysfs   defaults                0       0
up vote 14 down vote accepted

oops... my bad. It's as simple as mounting dev.

Strangely enough I tried this at about 1am last night and that didn't work. This morning it did, so I'm not sure what was different.

To get a full environment just

sudo chroot /media/flash-drive
mount proc
mount sys
mount dev

And in case you have a separate boot partition

mount boot

After doing that I was able to see my devices in /dev

And update-grub actually works. Now to figure out why it's not booting... that's another problem.

  • In 12.04, I had to mount udev rather than dev. – Randall Whitman Jul 25 '17 at 3:45

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