Optical Drive problems

[DK1090]

Hello all,

I am using MEPIS 6.5 on my Laptop. When I insert a CD or DVD into my drive it will spin the disk but MEPIS will not mount the disk. I have tried every mount option and command and still I can't get anything. I using an HP Pavilion dv2000 with a Lightscribe DVD burner/reader combo. Any help would be most appreciated.

[Nepomuk]

Hi DK1090!
Hm, does MEPIS recognise the drive itself? Please post the output of

ls /dev/?cd*

Also, what mount commands did you try? I don't believe, you tried all possible commands, as that would be a real lot - you probably tested those, that you think are realistic. So, which ones are that?

Greetings,
Nepomuk

[DK1090]

Hey man thanks for the help. I think I worked it out for myself. But if you could help me with this problem, that would be great.

I go to load my external HDD and when it mounts it says it's full but I can see no files (plus I deleted all the files) no files even with ls -a, but it says the HDD is full. I then go to cfdisk to repartition the disk and see if that is the problem but then it says that the disk has a bad primary partition and cfdisk closes. So I have nothing that I can think of.

[Nepomuk]

Hi again!

Hey man thanks for the help.

You're always welcome! :-)

I think I worked it out for myself.

OK, glad you worked it out. Just out of interest (and for any people, who might find this thread in future), what was the problem and how did you solve it?

I go to load my external HDD and when it mounts it says it's full but I can see no files (plus I deleted all the files) no files even with ls -a, but it says the HDD is full. I then go to cfdisk to repartition the disk and see if that is the problem but then it says that the disk has a bad primary partition and cfdisk closes. So I have nothing that I can think of.

Hm, what is the output of

fdisk -l /dev/sda

(or whatever device it is), run as root?

Also, do you need files, that are (or should be) on that primary partition? If so, we'll have to try to repair it, otherwise we could just create a new file system or even new partitions.

Greetings,
Nepomuk

[DK1090]

This is the output for /dev/sdb1

Disk /dev/sdb1: 79.0 GB, 79003782144 bytes
255 heads, 63 sectors/track, 9604 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

This doesn't look like a partition table
Probably you selected the wrong device.

Device Boot Start End Blocks Id System
/dev/sdb1p1 ? 119512 153402 272218546+ 20 Unknown
Partition 1 does not end on cylinder boundary.
/dev/sdb1p2 ? 82801 116350 269488144 6b Unknown
Partition 2 does not end on cylinder boundary.
/dev/sdb1p3 ? 33551 120595 699181456 53 OnTrack DM6 Aux3
Partition 3 does not end on cylinder boundary.
/dev/sdb1p4 * 86812 86813 10668+ 49 Unknown
Partition 4 does not end on cylinder boundary.

Partition table entries are not in disk order

This is the output for /dev/sdb

Disk /dev/sdb: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdb1 * 1 9605 77152131 83 Linux


Oh and for how I mounted the drive I feel really stupid but I just remounted from /dev/cdrom, my problem was that the disk that I kept trying wasn't able to load so I tried a new disk and it went right through.

[Nepomuk]

This is the output for /dev/sdb

Disk /dev/sdb: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdb1 * 1 9605 77152131 83 Linux

OK, that looks fine. Let's try to repair the file system. Make sure it's not mounted and type:

fsck -t ext3 -y /dev/sdb1 # I'm guessing, it's ext3

Now, it should find errors and attempt to correct them. Any files saved will be moved to the lost+found directory on that drive.
If that doesn't work, you could check if

parted /dev/sdb check 1

gives any other output.

If you have no need to save any files on the drive, you can also use

parted /dev/sdb rm 1
parted /dev/sdb mkpartfs ext3 1 9605

Oh and for how I mounted the drive I feel really stupid but I just remounted from /dev/cdrom, my problem was that the disk that I kept trying wasn't able to load so I tried a new disk and it went right through.

Everyone makes mistakes, so just remember and try to not make the same mistake again! :-D

Greetings,
Nepomuk

[DK1090]

With the fsck command I get

fsck -t ext3 -y /dev/sdb1
fsck 1.40-WIP (14-Nov-2006)
e2fsck 1.40-WIP (14-Nov-2006)
fsck.ext3: No such file or directory while trying to open /dev/sdb1

The superblock could not be read or does not describe a correct ext2
filesystem. If the device is valid and it really contains an ext2
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>

as output. Does this say anything.

[Nepomuk]

With the fsck command I get

fsck -t ext3 -y /dev/sdb1
fsck 1.40-WIP (14-Nov-2006)
e2fsck 1.40-WIP (14-Nov-2006)
fsck.ext3: No such file or directory while trying to open /dev/sdb1

The superblock could not be read or does not describe a correct ext2 filesystem. If the device is valid and it really contains an ext2 filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>

as output. Does this say anything.

Well, it sounds pretty obvious to me. But first of all: It is a ext3 system, isn't it? Because, if it isn't, we might be ruining the file system (and the files on it) with what I'll attempt to do next.

If it is ext3, try using the command given:

e2fsck -b 8193 /dev/sdb1

From the e2fsck manpage:

-b superblock

Instead of using the normal superblock, use an alternative superblock specified by superblock. This option is normally used when the primary superblock has been corrupted. The location of the backup superblock is dependent on the filesystem’s blocksize. For filesystems with 1k blocksizes, a backup superblock can be found at block 8193; for filesystems with 2k blocksizes, at block 16384; and for 4k blocksizes, at block 32768.

Additional backup superblocks can be determined by using the mke2fs program using the -n option to print out where the superblocks were created. The -b option to mke2fs, which specifies blocksize of the filesystem must be specified in order for the superblock locations that are printed out to be accurate.

If an alternative superblock is specified and the filesystem is not opened read-only, e2fsck will make sure that the primary superblock is updated appropriately upon completion of the filesystem check.

Sound's right, doesn't it? But as I said: Be very careful!

Greetings,
Nepomuk