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Getnikar
06-17-2006, 04:14 PM
I just downloaded the latest knoppix, burnt it and opened it via mount -o loop to check the download was OK. Then tried to boot my laptop with it to install it onto it. I tried both expert mode and standard mode. Under expert mode ...

Just after "Do you want to load additional modules from floppy disk? " (No), it enables DMA for hda (hard disk) and hdc (cdrom). Then reports ...

"Accessing KNOPPIX CD at /dev/hdc... /cdrom/KNOPPIX/modules/insmod: 1: Syntax error: "(" unexpected
Cant find KNOPPIX filesystem, sorry"

and drops me to a shell.

Under a standard boot, the problem as described is teh same, except Knoppix does not ask about loading stuff off a floppy.

The PC is a Toshiba Satellite 1800 900mHz notebook.

Is there a shell script coding bug there?

Getnikar
06-17-2006, 04:25 PM
The messages about DMA above were 2 lines, reporting using DMA on the hard disk and the CD, both of which were correctly identified by model.

I then tried to boot "knoppix nodma". Now the messages about using DMA disappear as expected. The problem is immediately after that, apparently when Knoppix tries to do the 'insmod' command.

Has anyone else had this problem? I cant believe only I am getting it.

Getnikar
06-17-2006, 05:04 PM
More info.

Exactly the same thing happens on an ASUS notebook.

OErjan
06-17-2006, 08:05 PM
this sounds like a bad burn and/or a faulty iso.
how did you download it?
did you check the MD5? (normally not needed if you use bittorrent)
did you burn it at a nice SLOW speed?

many similar problems come from burning too fast, 1-4X is best imho, but do it as sow as you can.
why slow burn? well serch this forum and you will see that a working burn may be "marginal"if to be used as bootmedia.

Getnikar
06-18-2006, 01:54 AM
OK, I found my problem. The downloader aget is stuffed. I have since now gone back to wget and all is OK..

I had downloaded the iso using aget. I had cancelled it at the end, as it had gone into a download loop. The iso seems OK, in that I could mount it with the loop option, burn and boot from it, but it actually had a bit or two missing.

The moral is : do not trust aget for downloads. Anyway wget got the iso just as fast.

Getnikar
06-18-2006, 01:55 AM
OErjan. Thanks for the advice.

The burn was fine. I used a new ASUS notebook and it burns fine at max speed.

MD5: I looked at man MD5, but could not work out the command to use. I needed an intro into it. I saw an intro somewhere yesterday... just gotta refind it! What is the command? something like 'md5 -??? xyz.md5 xyz' Am I close?

Harry Kuhman
06-18-2006, 02:23 AM
The burn was fine. I used a new ASUS notebook and it burns fine at max speed.l
When will people learn. It may look fine. It may verify fine. But experience has shown us repeatedly that it is not fine. At least until you get you boot working, burn at slow speed. After that if you want to burm CDs for yourself at high speed, go ahead.


MD5: I looked at man MD5, but could not work out the command to use. I needed an intro into it. I saw an intro somewhere yesterday... just gotta refind it! What is the command? something like 'md5 -??? xyz.md5 xyz' Am I close?
See the downloading faq for may different programs.

Getnikar
06-18-2006, 04:29 AM
Harry: Thanks for the advice.

I ran md5sum on the downloaded iso file. Its output is the same as in the .md5 on the website.
I burned the downloaded iso to cd again, this time at 4x speed.
Then I copied the cd back to hard disk as another iso. I ran "dd if=/hdc of=testcd.iso". I checked this with md5sum. The output of "md5sum testcd.iso" as the same as the above 2 md5 signatures. Am I correct that this proves that the cd is burnt correctly, and a true image of the distro?

Harry Kuhman
06-18-2006, 05:13 AM
Am I correct that this proves that the cd is burnt correctly, and a true image of the distro?
I don't know that there is any proof. The problem seem to be that there is a lot of error recovery data on a CD and the error recovery process can hide the occasional read error (as it is intended to do). But the error recovery process just doesn't seem to help at boot time. So we have repeatedly seen that disks burnt at high speed fail to boot in strange ways or, when they do boot, they boot much slower than they should. This happens even if the disc image has passed an MD5 test or was checked with the "verify image" option in Nero. See this thread (http://www.knoppix.net/forum/viewtopic.php?t=17788) and this one (http://www.knoppix.net/forum/viewtopic.php?p=78583#78583) and this one (http://www.knoppix.net/forum/viewtopic.php?p=78583#78583) for just a few examples.

So when people are fighting problems that sound like the high speed burn issues we have seen in the past, it's a pretty reasonable thing for us to suggest that they do their burns at low speed, it eliminates a potential contribution to boot problems that we have seen all too often.