kernel panic when booting LiveDVD

[ddp]

I downloaded KNOPPIX 5.3.1 LiveDVD with DAP (download manager), so I believe that the file is not corrupt.
I burnt it with Nero at 8x on a 16x certified disk. Data varified with success.

When booting and after the F2/F3 screens I get this message on 2 machines with completely different hardware. (AMD-EIDE vs Intel-SATA)

Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(1,3)

In failsafe and expert mode I was able to catch 2 more messages that might help you:

RAMDISK: Compressed image found at block 0
invalid compressed format (err=2)

and

Ns filesystem could not mount root tried: reiserf ext3 ext2 msdos vfat iso9660 fuseblk

[Harry Kuhman]

I downloaded KNOPPIX 5.3.1 LiveDVD with DAP (download manager), so I believe that the file is not corrupt.

I don't know if it's corrupt or not, but since you are getting a kernel panic, that should not be ruled out. Certainly not when there is a simple md5 test that will settle it once and for all. I personally never trust download managers, and while I know nothing at all about the one that you are using, the problems that I saw with corruption before BitTorrent downloads were available were caused by the servers, not by any bad ju-ju in the connections. I used to get about 50% corrupted downloads before torrent downlods became available, none afterwards. I strongly suggest that you do the md5 test (read the downloading faq if you are tempted to ignore that just because you have never done a md5 test before). This is so likely the source of the problem that there seems no reason to go on, but I want to also address the next line...

I burnt it with Nero at 8x on a 16x certified disk. Data verified with success.

8x is a pretty high data rate for a DVD. While it's at the upper limit of a speed that I might use for a CD, I personally think it's too fast for DVD burning. While I have no hard data to offer to prove this, I burn all of my DVD's at 4x, and would suggest that, at least until you get one that works, you use that speed also.

[ddp]

I have downloaded thousands of files with DAP and I have never had corrupt files without a warning.

What is a md5 test, please?

I have been writing all my dvds at 8x with no problems. From the error messages that I get I tend to believe that the dvd is corrupt at some point. Unfortunately, I wont be able to write a new one till Monday.

Is there anyway to verify that the dvd that I currently have is with no errors? I tried the testdvd option at the F2/F3 screens but I get the same error messages before the test even starts...

[Harry Kuhman]

I have downloaded thousands of files with DAP and I have never had corrupt files without a warning.

If you want advice from people who have gone over this many times before, fine. If you want to argue, I have better things to do. I've downloaded thousands of files also. I may have had some corrupt downloads from newsgroups, but can't be sure that the problem wasn't in the posting. Other than that I have never had a bad download other than when downloading the Knoppix ISO from a mirror, and about 1/2 of those went bad. I would love to place a bet right now that you have a bad download. BitTorrent is the prefered way to download the ISO (and, as a bonus, the related files). I have looked into this corruption and know exactly what is going wrong. (I'll bet that when this is done, if you get a good ISO, you find that the size of the ISO you have now is not exactly what it should be.) The fix is to use BitTorrent and not to use the mirrors. If you do have a corrupt ISO, I give you about a 50% chance of getting a good download the next time that you try, unless you are willing to learn to use BitTorrent .

What is a md5 test, please?

See answer #1.

I have been writing all my dvds at 8x with no problems. From the error messages that I get I tend to believe that the dvd is corrupt at some point. Unfortunately, I wont be able to write a new one till Monday.

Actually, not being able to write another until Monday is good, since if you make more burns before doing the md5 test you would just be cranking out more coasters, although you would be doing it at a rate twice as fast as I would. If you are willing to listen to someone who also used to burn at high speed before he found that he could no longer read some things that had been burnt fine and were verified at time of burn, and has seen this problem over and over again here, see these links:

http://www.knoppix.net/forum/viewtopic.php?t=17788

http://www.knoppix.net/forum/viewtop...?p=78582#78582

http://www.knoppix.net/forum/viewtopic.php?t=17064

Is there anyway to verify that the dvd that I currently have is with no errors? I tried the testdvd option at the F2/F3 screens but I get the same error messages before the test even starts...

Do the MD5 test against the ISO. If the ISO is bad I can assure you that the DVD is bad, no matter at what speed it was burned at. The testdvd option is good (it also does md5 tests), but it can't check everything and it can't run when you have a corrupted download.

[ddp]

Thank you.
All that I wanted to know is that it is not a configuration problem.
Either the iso is corrupt or the burning was with errors. I can fix both of these.

[OErjan]

sadly the data in a DVD or CD burned at high speed will likely be decently ok as such,
BUT the data may be in some of the backup sectors which are not that accessible to a operating system that is trying to start (still just basic hardware support)
also a MD5 check will prevent making coasters (bad burns) in most cases, specially if disk is then burned at low speed.

you can find much usefull information on the WIKI.
http://www.knoppix.net/wiki/Main_Page

read through this FAQ for information on Burning and MD5 among other topics.
http://www.knoppix.net/wiki/Downloading_FAQ
I strongly advise reading most of the FAQ, it may answer some more Questions you did not even know you should have asked.

I think the sections you are interested in are mainly the ones below (guess I make this too easy for you)
http://www.knoppix.net/wiki/Download...O_CD_images.3F
and
http://www.knoppix.net/wiki/Download..._using_NERO.3F

[Harry Kuhman]

Could we have an update on what has been learned? Monday has come and gone, and if you had the ISO file available the md5 test didn't need to wait until Monday. In any event it would be interesting to know what the problem here turned out to be and might allow us to better help others.

[ddp]

corrupt ISO.
Re-downloading