Boot is halted by supposedly missing drive

Do you have a OS installed on this external drive ?

Question 1: Have you tried to press "S" for skip?

Question 2: You say you had backed up and restored all your files. What do you mean by "all" your files. I would recommend to restore only files under /home/your-user-name but also leave all directories and files starting with a dot (hidden files) out until you know exactly what you are doing.

Question 3: Could you please copy paste the contents of your file /etc/fstab here

No, I don't have an OS on the external drive. It's just for backup of my Home folder.

I have to press S for skip if I want the computer to get past this screen. Otherwise, the computer would be stuck forever on this screen!

How / where do I find /etc/fstab?

How / where do I find /etc/fstab?
      more /etc/fstab

Disconnect all USB drives and do
      sudo grub-install /dev/sda
to rebuild boot file.

Can you do also
     sudo blkid && sudo parted -l
and post results.

This is OK:

> Can you do also
> sudo blkid && sudo parted -l
> and post results.

This could be dangerous in some cases (probably rare, but better to be cautious)

> Disconnect all USB drives and do
> sudo grub-install /dev/sda
> to rebuild boot file.

I would not run it until wee have seen your

more /etc/fstab
sudo blkid
sudo parted -l

results.

Unfortunately, if he has Grub2, I know no other options, as grub2 do all automatically instead of Grub1.
But a very good question is: is Grub1 or Grub2 installed ?
Can you type:

        grub --version

Grub1 will answer you 0.97 (yes, 0.97 is 1)
With Grub2, you will get an error message (Grub2 is 1.97 or 1.98!)

Well I wouldn't expect that grub causes the problem at all. Grub should only be aware of the boot file system and root file system.

If skipping the mount suucceeds and ends up in a functional machine it is obviosly not the boot file system and not root file system that is causing trouble here.

I have seen the same file "system not ready" message after making a hardware configuration change and /etc/fstab did still refer to the old device names.

I typed grub --version and the response was that grub is not installed at all!

Here's my fstab:

# /etc/fstab: static file system information.
#
# <file system> <mount point> <type> <options> <dump> <pass>

proc /proc proc nodev,noexec,nosuid 0 0
#Entry for /dev/sda1 :
UUID=2cbac45a-5068-40dc-9f89-9903f2c0f65a / ext4 errors=remount-ro 0 1
#Entry for /dev/sdb1 :
UUID=5E27050667E0DDCC /media/5E27050667E0DDCC ntfs-3g defaults,nosuid,nodev,locale=en_GB.UTF-8 0 0
#Entry for /dev/sda5 :
UUID=eaa05602-ae50-4a9a-9959-58be66a0c5c7 none swap sw 0 0
/dev/fd0 /media/floppy0 auto rw,user,noauto,exec,utf8 0 0

I've just noticed looking more carefully at that fstab output that the second UUID is the serial number of the drive that comes up with the error message. That's definitely my USB drive as it's NTFS. Until yesterday, this was the drive where I backed up my Home Folder. Yet I have connected it, the computer has seen it, then I re-booted and left it for two hours and - nothing! Only by pressing S will boot continue to the desktop.

Do a backup of /etc/fstab and remove the line about /dev/sdb1.
Mount try to manage this disk as an internal disk and not an external disk.

Yes that is exaclty what I expected. The line for /dev/sdb1 looks weird. Comment it out or remove it.

Boot without the USB stick inserted. It should work now.

If you insert the USB stick later, does it get mounted automatically?

Before you pull it out you should always select Eject in the user interface before actually pulling it.

Just tried to edit fstab but it won't let me. Looked at the permissions and they're all for Root. You use sudo to do things as root, do you not? How do I open it as root?

Thanks.

sudu chmod u+w /etc/fstab ; sudo gedit /etc/fstab

Done that. Rebooted and it now says "error booting 0" I had to press S to continue booting.

Can you post results of:
       more /etc/fstab; sudo blkid; sudo parted -l

Here's fstab:

# /etc/fstab: static file system information.
#
# <file system> <mount point> <type> <options> <dump> <pass>

proc /proc proc nodev,noexec,nosuid 0 0
#Entry for /dev/sda1 :
UUID=2cbac45a-5068-40dc-9f89-9903f2c0f65a / ext4 errors=remount-ro 0 1
#Entry for /dev/sdb1 :
defaults,nosuid,nodev,locale=en_GB.UTF-8 0 0
#Entry for /dev/sda5 :
UUID=eaa05602-ae50-4a9a-9959-58be66a0c5c7 none swap sw 0 0
/dev/fd0 /media/floppy0 auto rw,user,noauto,exec,utf8 0 0

Here's blkid:

/dev/sda1: UUID="2cbac45a-5068-40dc-9f89-9903f2c0f65a" TYPE="ext4"
/dev/sda5: UUID="eaa05602-ae50-4a9a-9959-58be66a0c5c7" TYPE="swap"

Here's parted -l:

Model: ATA SAMSUNG HD753LJ (scsi)
Disk /dev/sda: 750GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
 1 1049kB 744GB 744GB primary ext4 boot
 2 744GB 750GB 6139MB extended
 5 744GB 750GB 6139MB logical linux-swap(v1)

fstab looks perfectly correct.
Perhaps Uwe Geuder will have an idea, which is not my case.
Could you provide as much information you can on the boot process until error appears and provide if possible a copy/paste of error ?

Thank you all for your help - it's really appreciated. I think that it's going to be easier to backup my files and re-install!

Yes, it could be easier.
You have only to backup /home directory, but you have special configuration.

I don't think a reinstall is needed. The problem is very clear.

> sudu chmod u+w /etc/fstab

I guess this was a typo, sudu should have been sudo. Anyway that command should not be necessary.

In order to edit a file owned by root one typically uses "sudo -e"

sudo -e /etc/fstab

Any there are many choices and you obviously managed to edit the file. But you didn't remove the line in question completely:

> #Entry for /dev/sdb1 :
> defaults,nosuid,nodev,locale=en_GB.UTF-8 0 0
> #Entry for /dev/sda5 :

There is stil that defaults,... stuff.

You have 2 choices:

1. delete the line completely
or
2. change the line to a comment by inserting a # as its first character.

Quite often one uses the commenting choice, because then it's easy to get the original thing back if something goes wrong.
However, now you already deleted parts of the line so the rest doesn't make any sense any more. So you can delete the rest as well. But that's all a matter of human taste, the machine doesn't care.

Uwe, thanks for your further response but I wiped the drive and re-installed! Now I enjoy a wonderfully quick boot like every other Ubuntu user!

Thank you and to everybody else for all your help - I learned a lot!

Charlie

Uwe is right. I missed the line.
It's the end of previous line of "/dev/sdb1".
Perhaps "mount" can't analyze the file with this error.

I'm having a very similar problem. I updated from 9.1 (Karmic) to 10.01 (Lucid) with a wubi install inside Windows XP, and i received the message ""The disk drive for **name of the disk** is not ready yet or not present. Continue to wait or press S to skip mounting or M for manual recovery". As it use to happen, "Continue" is absolutely useless. I tried with M and "blkid" and didn't work. So i use to skip. But my links don't work and i've to go to Computer to click in my disks and work with folder and files. I tried to change fstab and it didn't work, i don't know how to do it right. I want to use UUID to make it fine but i made it worst.

Here is my fstab:

# /etc/fstab: static file system information.
#
# <file system> <mount point> <type> <options> <dump> <pass>

proc /proc proc defaults 0 0
/dev/sdb1 /host ntfs-3g defaults,nosuid,nodev,locale=es_CO.utf8 0 0
/dev/sdb1 /media/SISTEMA ntfs-3g defaults,locale=es_CO.utf8 0 0
/host/ubuntu/disks/boot /boot none bind 0 0
/host/ubuntu/disks/swap.disk none swap loop,sw 0 0
/dev/fd0 /media/floppy0 auto rw,user,noauto,exec,utf8 0 0
/dev/sdb5 /media/ARCHIVOS ntfs-3g defaults,locale=es_CO.UTF-8 0 0

I go to /media/ and find my disks duplicated: ARCHIVOS and ARCHIVOS_, SISTEMA and SISTEMA_, even the cdrom! I can not unmount SISTEMA, i don't know why. I didn't make a backup of the original fstab, sorry. But the message appear almost everytime. It's a nice surprise when everything work fine, but, if i have to re-boot, it will appear again.

Thanks for your help.

The comments in the beginning of /etc/fstab tell you the meaning of each parameter. Parameters are separated by white space.

Your file system in /dev/sdb1 is mounted to 2 places (called mount points).
See lines 2 and 3 of your /etc/fstab (only non-comment and non-empty lines counted). Please decide for one and comment the other line.

You don't have an entry for your root file system. Not sure how that works. Do0 you know where it is? Does it get mounted?

@benditoelqueviene

/dev/sdb1 /host ntfs-3g defaults,nosuid,nodev,locale=es_CO.utf8 0 0
/dev/sdb1 /media/SISTEMA ntfs-3g defaults,locale=es_CO.utf8 0 0

You have two times /dev/sdb1, but I think you can't mount a partition on two folders.
If SISTEMA is an external drive, it should be simpler to remove it from /etc/fstab, and let automount daemon manage it when it is plugged.

What is your hardware configuration ? one internal disk and many external disk ?

Usually, the internal disks are enumerated /dev/sda, /dev/sdb, ... and have a fixed location as folder.
External USB drive are enumerated /dev/sdg, /dev/sdh, ...
For external SATA, I don't know (I presume hot-plug means /dev/sdg/ and cold-plug /dev/sda).