[SOLVED] Start up error

[kd0afk]

I have installed ubuntu on my laptop (see this link for all of the juicy details) http://www.linuxforums.org/forum/ubu...d-windoze.html
Now when I start my computer up I get this error:
Insert system disk in drive.
Press any key when ready.

[kd0afk]

I have been researching this problem and I think that my master boot record is corrupt. Might have happened during the many times the install froze up.
If anyone has any insight or clarity on this please let me know.

[yancek]

Haven't read your other post but it could be the mbr corrupt, not partitioned or formatted or the simplest, a non-bootable floppy in the drive.

[D-cat]

Or the MBR does not contain boot code, so it looks for it in the first track of the "active" partition, which I suspect now no longer exists.

Please boot with your live CD, open a terminal window, and post the output of
sudo fdisk -l (that's FDISK -L in lower case).

[Rubberman]

Or the MBR does not contain boot code, so it looks for it in the first track of the "active" partition, which I suspect now no longer exists.

Please boot with your live CD, open a terminal window, and post the output of
sudo fdisk -l (that's FDISK -L in lower case).

Actually, that's what the default bootloader does. It reads sector 0 of the disc (the boot loader + partition table), finds the active partition, loads the first sector of that, relocates and executes that code, which then knows where to find the real operating system. It is possible that the BIOS, not finding any valid boot code in sector 0 will do that itself. I don't know since the last time I wrote a PC boot loader was in 1986-87. You'd be amazed what you can do in under 500 bytes of machine code! Just so you know, the boot sector is only 512 bytes, including the partition table.

[D-cat]

Even in the absence of a boot loader in the MBR, the BIOS will still seek out the first sector of the active partition. If there is no active partition or no boot code in it, and no other BIOS defined boot devices located, then the above message will be displayed.

I've been working with computers since the Apple ][e. Yes, you can stick the boot loader in the active partition, which is the right way to do it IMO; makes other OS installs wiping the MBR a non-issue. But, since that's not the way it's normally done any more, we have tools like SuperGrub! ...which will likely be used to fix this problem providing that the linux partition is still in tact.

[Rubberman]

Even in the absense of a boot loader in the MBR, the BIOS will still seek out the first sector of the active partition. If there is no active partition or no boot code in it, and no other BIOS defined boot devices located, then the above message will be displayed.

I've been working with computers since the Apple ][e. Yes, you can stick the boot loader in the active partition, which is the right way to do it IMO; makes other OS installs wiping the MBR a non-issue. But, since that's not the way it's normally done any more, we have tools like SuperGrub! ...which will likely be used to fix this problem providing that the linux partition is still in tact.

Sounds rational to me. Like I said, my last stint writing boot loaders was back in the mid-80's. Things have changed (sometimes for the better) in the past 20-25 years...

[kd0afk]

Here is what fdisk popped out.
Disk /dev/sda: 40.0 GB, 40007761920 bytes
255 heads, 63 sectors/track, 4864 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x8b798b79

Device Boot Start End Blocks Id System
/dev/sda1 1 160 1285168+ 83 Linux
/dev/sda2 161 4864 37784880 5 Extended
/dev/sda5 4684 4864 1453851 82 Linux swap / Solaris
/dev/sda6 161 4502 34877052 83 Linux
/dev/sda7 4503 4683 1453851 82 Linux swap / Solaris

Partition table entries are not in disk order

[yancek]

You have two Linux partitions, sda1 and sda6. Assuming sda1 has your system files and sda6 is a /home or other partitions, load your installation CD and run the command 'sudo grub' in a terminal to get the Grub prompt (grub>). Then type:

root (hd0,0)
setup (hd0)
quit

If you system files are on sda6, change the entries accordingly. If this fails, post any error messages you get. You could try mounting your partitions with your install CD:

sudo mkdir /mnt/ubuntu
sudo mount -t ext3 /dev/sda1 /mnt/ubuntu

Then navigate to the newly created ubuntu directory to see if boot files are there.

ls -l /mnt/ubuntu

Post any error messages if you don't get results.

[kd0afk]

sniped:
If you system files are on sda6, change the entries accordingly.

Change the entries accordingly how?