Quote Originally Posted by kl522 View Post
What you are saying, in theory, it should not happen. But if it at all happens, it MUST be a software bug, or a physical corruption. Physical corruption will like be irrecoverable. If it can be recovered by wiping it out, then it points more likely that it is a SOFTWARE bug somewhere.

Why do I say that ? Because /mnt-system/KNOPPIX/KNOPPIX is a read only file system, and it is aufs2-ed with /mnt-system/KNOPPIX/knoppix-data.img. Both of these are fixed sized. It will not grow, at run time, beyond it's pre-configured size.

It might not be worthwhile for you to investigate it down the software corruption problem, unless you intend to be a knoppix guru and so on. But if I were in that situation, I will do things like :-

a) Boot KNOPPIX CD, first run dosfsck or fsck.vfat and so on on the VFAT partition to check for possible VFAT corruption
b) Boot from KNOPPIX CD, manually cloop-mount the flash KNOPPIX compressed image, to see if that is possible to see the problem this way.
c) Boot from KNOPPIX CD, e2fsck on knoppix-data.img to check for corruption and possible loop mount it manually and check for corruption.

Cheers.
This is, I think, very good general trouble-shooting advice.
I would also like to point to the krishna.murphy's advice about backup of knoppix-data.img.

As for the problem, I think is occurs mainly because of too small drive and too little persistent storage. I would say that if you are not sure about the need, set up 4GB for persistent storage. Which, in practice, means at least 8GB sticks.

I think there is kind of bug in Knoppix in space allocation. It will let you fill up persistent storage entirely, and then crash, maybe without any warning at all. And if you are doing package installs and updates, persistent storage can fill up VERY quickly. I have produced that condition myself, but I didn't care to look at knoppix-data.img afterwards. I would guess that I could just loop-mount it post mortem and, mostly, get necessary data off it.