Ubuntu boot error: unable to access tty

Q When I try to run or install Ubuntu, I get the following message after the splash screen comes up: 'unable to access tty, job control turned off' and am returned to a terminal prompt. Ubuntu apparently is trying to access my floppy drive for some reason because the floppy drive turns on until I get the error message.

A It appears that this error is caused by the kernel being unable to find your boot drive, so the floppy drive light comes on because it is trying every device listed in the BIOS. As there are a couple of reported causes of this problem, there's more than one possible solution. One is to boot from the install disc and edit the fstab of your installed system. If your root partition is on /dev/sda1, the commands you need are

sudo -i
mount /dev/sda1 /mnt
gedit /mnt/etc/fstab

You should see the line that mounts your root partition in fstab, it will look something like

# /dev/sda1
UUID=71f72f22-0a14-45b7-9057-f7b0bd9d819c /  ext3 defaults....

The UUID (Universally Unique IDentifier) should enable Ubuntu to find the root partition, even if your device nodes change (such as adding another disk), but it can cause problems here. Change the UUID=xyz string back to the device node and your system should boot again. The fstab line should now look like:

# /dev/sda1
/dev/sda1 / ext3 defaults....

The other solution is more extreme, so only try it if the fstab trick fails. You need to open your computer and disconnect any extra hard and CD/ DVD drives, leaving only your boot drive and the DVD from which you installed - turn off the computer first! Disconnect the floppy drive too, removing the power cables from the unneeded devices should be sufficient. Your system should now boot. Then you add the piix module to the ramdisk image that Ubuntu loads when it boots with these terminal commands

sudo echo piix >>/etc/initramfs-tools/modules
sudo update-initramfs -u

You should now be able to shut down, reconnect the devices and start up. This bug appears to affect a small number of Ubuntu users, and only those with multiple drives fitted. It has also been reported that when the problem is caused by a floppy drive, it can be circumvented by leaving a disk in the drive, but we were unable to verify this and it sounds like a kludge anyway.

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