Author Topic: (SOLVED) Got "Error 21" message when in GRUB  (Read 16346 times)

batzilla

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(SOLVED) Got "Error 21" message when in GRUB
« on: September 04, 2012, 01:56:57 PM »
I was on my computer, minding my own business, and the tool bar at the bottom of the page went away and I was stuck.  So I manually shut down my computer and on booting again, got a black screen with this message:

GRUB Loading stage1.5.

GRUB Loading, please wait. . . .
Error 21

Can somebody rescue me!?  I'm running PCLinuxOS 2009 release 2.6.26.8.tex3 with KDE 3.5.10 on a Dell Dimension 4500.

Batzilla
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Offline Legs11

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Re: Got "Error 21" message when in GRUB
« Reply #1 on: September 04, 2012, 02:32:13 PM »
Quote
21 : Selected disk does not exist
      This error is returned if the device part of a device- or full
      file name refers to a disk or BIOS device that is not present or
      not recognized by the BIOS in the system.

From   info:/grub/Stage2 errors   .....  you can use Konqueror to see all the error messages by entering that in the location bar.

I would suggest checking the cables ....  power and data going to the disk .....  pull them and reseat them with the power unplugged.
Then try to boot again.

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T6

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Re: Got "Error 21" message when in GRUB
« Reply #2 on: September 04, 2012, 02:36:39 PM »
you are using a really old version of pclinux!  any reason to do that?

error 21, wasn't that error related to the hard disk partitions?  backup your important files just in case that partition or hard disk are failing

supposedly you can fix this error by running the redombr tool to recreate the mbr file or restore it but i don't remember if this tool exist in the livecd of 2009 or we have that tool since 2010
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Offline Old-Polack

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Re: Got "Error 21" message when in GRUB
« Reply #3 on: September 04, 2012, 02:39:55 PM »
I was on my computer, minding my own business, and the tool bar at the bottom of the page went away and I was stuck.  So I manually shut down my computer and on booting again, got a black screen with this message:

GRUB Loading stage1.5.

GRUB Loading, please wait. . . .
Error 21

Can somebody rescue me!?  I'm running PCLinuxOS 2009 release 2.6.26.8.tex3 with KDE 3.5.10 on a Dell Dimension 4500.

Batzilla

From the grub manual:

21 : Selected disk does not exist
      This error is returned if the device part of a device- or full
      file name refers to a disk or BIOS device that is not present or
      not recognized by the BIOS in the system.

Shut down and check the physical connections to your hard drive. Unplug the data cable at both ends, and reseat, a couple of times, to insure good contact on all the pins. Replace the cable with a new one if need be. Unplug and reseat the 4 pin Molex power connector to the drive also. If it feels even the least bit loose, try a different Molex connector.

Check to be sure there are no USB sticks left attached during boot up, unless you are actually trying to boot from the USB stick.
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Old-Polack

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batzilla

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Re: Got "Error 21" message when in GRUB
« Reply #4 on: September 04, 2012, 03:45:14 PM »
you are using a really old version of pclinux!  any reason to do that?

error 21, wasn't that error related to the hard disk partitions?  backup your important files just in case that partition or hard disk are failing

supposedly you can fix this error by running the redombr tool to recreate the mbr file or restore it but i don't remember if this tool exist in the livecd of 2009 or we have that tool since 2010

I'm using the older version, because it has worked so well, I really didn't need to, until I couldn't watch some of the videos on my news channel.  Kept telling me to upgrade FlashPlayer!

I can't run the redombr tool because I can't get that far.

Hey, Old-Polack.  Long time no see.  I'm still working on my upgrade problem.
I unplugged the computer and unplugged the data cables and the 4 pin Molex power connector a couple of times and made sure they were reseated well.  Then when I rebooted, I got this message:

  Booting 'Linux-nonfb'

Kernel (hd0,0)/boot/vmlinuz BOOT_IMAGE=linux-nonfb root=UUID=eda7fcdf-0131-48f7-9c47-40ec0027fe72 acpi=on RESUME=UUID=41ebc2ae-888e-497f-9de2-b7de288a1053

Error 15:  File not found

Press any key to continue. . .

When I press a key, I get this:

GNU GRUB version 0.97 (639K lower / 522496K upper memory)

Below that is a pale blue box with-

linux
linux-nonfb
failsafe

I tried all three, but they all sent me back to the previous message.

Thanks, guys

Batzilla
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T6

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Re: Got "Error 21" message when in GRUB
« Reply #5 on: September 04, 2012, 04:24:15 PM »
"I can't run the redombr tool because I can't get that far"

redombr from a livecd from that year, not from the install, i know it is not booting

still, remember my recomendation, save important files if the partition is failing
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Offline Old-Polack

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Re: Got "Error 21" message when in GRUB
« Reply #6 on: September 04, 2012, 05:01:11 PM »
"I can't run the redombr tool because I can't get that far"

redombr from a livecd from that year, not from the install, i know it is not booting

still, remember my recomendation, save important files if the partition is failing

Redo-mbr will do nothing to solve the problem. Grub has already found the menu.lst as shown by the list of menu choices. The fact that it now shows an error 15 means there is a second problem, it either can't find the kernel or the initrd.img. (kernel most likely)

15 : File not found
      This error is returned if the specified file name cannot be found,
      but everything else (like the disk/partition info) is OK.

Running an fsck from the liveCD may or may not fix the problem, but it is most likely corruption caused to the file system, as the disk connection failed, which also caused the previous error 21.

batzilla:

Considering all the other recent events, can you, in fact, boot to the liveCD from which you did your original installation?

If you can, from a terminal, as root:

[root@localhost ~]# fsck -fy /dev/sda1                              <Enter>

This assumes your / partition is on the first partition of your hard drive, as the error message implies. (reference to (hd0,0))

Post your results.
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Old-Polack

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batzilla

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Re: Got "Error 21" message when in GRUB
« Reply #7 on: September 04, 2012, 05:14:08 PM »
Thanks, Old-Polack, I was about to run redombr when I got your post.  I was able to boot with the LiveCD and ran your command line.  Here's what I got:

[root@localhost root]# fsck -fy /dev/sda1
fsck from util-linux-ng 2.16
e2fsck 1.41.9 (22-Aug-2009)
fsck.ext2: No such file or directory while trying to open /dev/sda1

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>

I just had a thought.  I am running two hard drives.  One with XP and the other with Linux.  This was a question I was going to bring up in another thread.  Before I installed pclinuxos 2009 over my older version, I was able to boot to either HD.  When I installed 2009, it wrote its own GRUB, which I'm assuming doesn't recognize the other hard drive.  I didn't care at the time, because I never use that other OS anymore.  I said all that to say, I've noticed that my drives are /dev/hdb1, etc.  Would that mean that I need to run your command line with hdb1 instead of sda1?
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batzilla

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Re: Got "Error 21" message when in GRUB
« Reply #8 on: September 04, 2012, 05:44:11 PM »
you are using a really old version of pclinux!  any reason to do that?

error 21, wasn't that error related to the hard disk partitions?  backup your important files just in case that partition or hard disk are failing

supposedly you can fix this error by running the redombr tool to recreate the mbr file or restore it but i don't remember if this tool exist in the livecd of 2009 or we have that tool since 2010

I've seen other posts about saving files on your installed OS by using the LiveCD.  How is that done exactly?  How do you get access to the installed OS from the LiveCD?
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T6

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Re: Got "Error 21" message when in GRUB
« Reply #9 on: September 04, 2012, 06:17:37 PM »
"I've seen other posts about saving files on your installed OS by using the LiveCD.  How is that done exactly?"

while the livecd is loaded and working, you can open your home folder and copy your own files from the hard disk without problems to the new place, a external usb driver or hard disk

just open konqueror(onthe old iso, new iso use dolphin) and search the partition where you store those files in the hard disk it has /home/thenameofyouruser

about dualbooting, pclinux can boot to another hard disk or another partition without problems, my desktop has two hard disks and does that nicely, pclinux 2010 updated and xp home, my netbook does that too but on one hard disk, 2010 updated and hp home

"Redo-mbr will do nothing to solve the problem. Grub has already found the menu.lst as shown by the list of menu choices. The fact that it now shows an error 15 means there is a second problem, it either can't find the kernel or the initrd.img."

thank you for the explanation, i made the suggestion based on old info of a old post i found on internet, i never done that but the explanation had some sense  :-\
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Offline Old-Polack

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Re: Got "Error 21" message when in GRUB
« Reply #10 on: September 04, 2012, 11:00:07 PM »
Thanks, Old-Polack, I was about to run redombr when I got your post.  I was able to boot with the LiveCD and ran your command line.  Here's what I got:

[root@localhost root]# fsck -fy /dev/sda1
fsck from util-linux-ng 2.16
e2fsck 1.41.9 (22-Aug-2009)
fsck.ext2: No such file or directory while trying to open /dev/sda1

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>

I just had a thought.  I am running two hard drives.  One with XP and the other with Linux.  This was a question I was going to bring up in another thread.  Before I installed pclinuxos 2009 over my older version, I was able to boot to either HD.  When I installed 2009, it wrote its own GRUB, which I'm assuming doesn't recognize the other hard drive.  I didn't care at the time, because I never use that other OS anymore.  I said all that to say, I've noticed that my drives are /dev/hdb1, etc.  Would that mean that I need to run your command line with hdb1 instead of sda1?


If you know that /dev/hdb1 is the installed / partition, and /dev/hdb is the boot drive, then /dev/hdb1 is what should be used in the command.

The newer PCLinuxOS releases see all hard drives as /dev/sdx due to changes to the kernel since your installed OS was released.
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Old-Polack

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batzilla

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Re: Got "Error 21" message when in GRUB
« Reply #11 on: September 05, 2012, 07:36:59 PM »
If you know that /dev/hdb1 is the installed / partition, and /dev/hdb is the boot drive, then /dev/hdb1 is what should be used in the command.
[/quote]

I think I know that /dev/hdb1 is the installed / partition, and /dev/hdb is the boot drive.  I ran fsck -fy /dev/hdb1 and this is what I got:

[root@localhost root]# fsck -fy /dev/hdb1
fsck from util-linux-ng 2.16
e2fsck 1.41.9 (22-Aug-2009)
/dev/hdb1 is mounted.

WARNING!!!  Running e2fsck on a mounted filesystem may cause
SEVERE filesystem damage.

Do you really want to continue (y/n)?

This makes me very uneasy!   :-\  Let me tell you how I came to the conclusion that /dev/hdb1 is the installed / partition.
I'm still in the LiveCD.  When I go to PCC and then go to Hardware, it lists under "Hard Disks" hda hdb, and sda.  When I click on hdb, Under Device it says "old device file: /dev/hdb."  Then under Partitions, it says, "Primary Partitions 1 (hdb1).  Under Extended Partitions, it says, "2 (hdb5), hdb6).  When I open Konqueror, system:/ , I get "Aps", "Home Folder", Print System, etc. until it gets to "Storage Media".  Under that it shows :
307G Media (which is hdb)?
79G Media (which is the a drive with Windoze)
8.4G Media (Which is Cruzer 8.4G stick)
For some reason, it doesn't show the CD drive.  Well, under the CDROM  it shows sr0, but in the description, it says it's the 8.4G ScanDisk Cruzer.  It shows the floppy.  ???

What throws me is, when I click on the 307G Media, it tells me it's at system:/media/hdb6.
When I click on 8.4G Media, it tells me it's at system:/media/hdb1
.  I removed the memory stick, but it still shows.  Maybe I have to reboot to get rid of it.

Well, that's where I am.  I hope I didn't muddy the water.

Batzilla
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Offline Old-Polack

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Re: Got "Error 21" message when in GRUB
« Reply #12 on: September 05, 2012, 08:05:58 PM »
If you know that /dev/hdb1 is the installed / partition, and /dev/hdb is the boot drive, then /dev/hdb1 is what should be used in the command.

I think I know that /dev/hdb1 is the installed / partition, and /dev/hdb is the boot drive.  I ran fsck -fy /dev/hdb1 and this is what I got:

[root@localhost root]# fsck -fy /dev/hdb1
fsck from util-linux-ng 2.16
e2fsck 1.41.9 (22-Aug-2009)
/dev/hdb1 is mounted.

WARNING!!!  Running e2fsck on a mounted filesystem may cause
SEVERE filesystem damage.

Do you really want to continue (y/n)?

This makes me very uneasy!   :-\  Let me tell you how I came to the conclusion that /dev/hdb1 is the installed / partition.
I'm still in the LiveCD.  When I go to PCC and then go to Hardware, it lists under "Hard Disks" hda hdb, and sda.  When I click on hdb, Under Device it says "old device file: /dev/hdb."  Then under Partitions, it says, "Primary Partitions 1 (hdb1).  Under Extended Partitions, it says, "2 (hdb5), hdb6).  When I open Konqueror, system:/ , I get "Aps", "Home Folder", Print System, etc. until it gets to "Storage Media".  Under that it shows :
307G Media (which is hdb)?
79G Media (which is the a drive with Windoze)
8.4G Media (Which is Cruzer 8.4G stick)
For some reason, it doesn't show the CD drive.  Well, under the CDROM  it shows sr0, but in the description, it says it's the 8.4G ScanDisk Cruzer.  It shows the floppy.  ???

What throws me is, when I click on the 307G Media, it tells me it's at system:/media/hdb6.
When I click on 8.4G Media, it tells me it's at system:/media/hdb1
.  I removed the memory stick, but it still shows.  Maybe I have to reboot to get rid of it.

Well, that's where I am.  I hope I didn't muddy the water.

Batzilla

Never do an fsck with the target partition mounted. If asked "Do you really want to continue (y/n)?" always choose no. Always unmount a partition on a USB stick before removing it. If unsure what the running system actually sees the hard drives as, run the command fdisk -l to see all the drives and partitions.
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Old-Polack

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batzilla

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Re: Got "Error 21" message when in GRUB
« Reply #13 on: September 06, 2012, 08:10:04 PM »
If you know that /dev/hdb1 is the installed / partition, and /dev/hdb is the boot drive, then /dev/hdb1 is what should be used in the command.

I think I know that /dev/hdb1 is the installed / partition, and /dev/hdb is the boot drive.  I ran fsck -fy /dev/hdb1 and this is what I got:

[root@localhost root]# fsck -fy /dev/hdb1
fsck from util-linux-ng 2.16
e2fsck 1.41.9 (22-Aug-2009)
/dev/hdb1 is mounted.

WARNING!!!  Running e2fsck on a mounted filesystem may cause
SEVERE filesystem damage.

Do you really want to continue (y/n)?

This makes me very uneasy!   :-\  Let me tell you how I came to the conclusion that /dev/hdb1 is the installed / partition.
I'm still in the LiveCD.  When I go to PCC and then go to Hardware, it lists under "Hard Disks" hda hdb, and sda.  When I click on hdb, Under Device it says "old device file: /dev/hdb."  Then under Partitions, it says, "Primary Partitions 1 (hdb1).  Under Extended Partitions, it says, "2 (hdb5), hdb6).  When I open Konqueror, system:/ , I get "Aps", "Home Folder", Print System, etc. until it gets to "Storage Media".  Under that it shows :
307G Media (which is hdb)?
79G Media (which is the a drive with Windoze)
8.4G Media (Which is Cruzer 8.4G stick)
For some reason, it doesn't show the CD drive.  Well, under the CDROM  it shows sr0, but in the description, it says it's the 8.4G ScanDisk Cruzer.  It shows the floppy.  ???

What throws me is, when I click on the 307G Media, it tells me it's at system:/media/hdb6.
When I click on 8.4G Media, it tells me it's at system:/media/hdb1
.  I removed the memory stick, but it still shows.  Maybe I have to reboot to get rid of it.

Well, that's where I am.  I hope I didn't muddy the water.

Batzilla

Never do an fsck with the target partition mounted. If asked "Do you really want to continue (y/n)?" always choose no. Always unmount a partition on a USB stick before removing it. If unsure what the running system actually sees the hard drives as, run the command fdisk -l to see all the drives and partitions.

I think I have messed up!  I assumed the 8.4G Media was the memory stick, because it was an 8G stick.  But, the fact is, the 8.4G Media is hdb1.  I now have two more questions!

1.  I tried to copy my files to the 8.4G Media (hdb1), thinking it was the memory stick, and now hdb1 is full.  Is there any way I can get back to where I started? (Probably not.)  It doesn't appear that my files have been lost, but I don't know what to delete from hdb1 to get some memory back on hdb1.  Any suggestions?

2.  Since I got the WARNING!!!! that /dev/hdb1 is mounted and I shouldn't run e2fsck on a mounted filesystem, do I unmount /dev/hdb1?  That won't work, will it?  And why is it telling me not to run e2fsck when I ran fsck?

Thanks,
Batzilla
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T6

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Re: Got "Error 21" message when in GRUB
« Reply #14 on: September 06, 2012, 08:32:02 PM »
at this point the easiest route is stop running commands and just open the partitions with the livecd loaded and copy everything that is important for you to another device

later just format the partitions that need to be formated but since you have multiple partitions i cannot tell you what to delete, copy or format, specially because you are not sure what you have and where you have it

probably old pollack can help you resolve what partitions you have and what each partition contains to determine what to save from where
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