[Laurence]

OK, I have noticed something strange in 10.2.x (I'm using 10.2.6, but I don't think it is limited to that release) that can cause file corruption in areas of the HD that should be inaccessible to applications. A little background...

I've been having kernel panics more and more often lately, and after each one I would fsck and repair permissions. Then i discovered what was causing at least some of the KPs. There was one or more files on the HD that were corrupt in some way. I discovered which files were damaged (in a way undetectable by fsck) by running carbon copy cloner and cloning the drive to a newly formatted drive. CCC would KP at some point during the process and I would reboot and see where the clone operation had stopped. The first time it was a movie file I had recently downloaded so I deleted it off both the original drive and the clone and then started CCC again. A few more files caused the KP and I deleted them as well. Now I could clone the entire drive without errors and everything seemed fine. I assumed that there was something wrong with the few files I had downloaded and didn't really worry about it, even though I knew that a damaged data file should NEVER cause a KP, maybe an error during the copy operation, but not a KP. I set CCC to backup every night at 1:00 am and display the log. for a few weeks everything worked as expected. Then one morning I turn on the monitor and there is another KP screen waiting for me. I had been downloading some more DivX movies recently, so i thought that it could be one of them causing the crash during backup again. I formatted the backup drive and ran CCC again... this time it turns out that the file preventing CCC from finishing without the KP was at /Library/Printers/Lexmark/... Since I don't have a lexmark printer I deleted the folder and everything was fine again but this doesn't make sense. Me downloading anything to my downloads folder on the desktop should not be able to modify files on the HD that should be protected by the built in UNIX permissions. (I did not have write access to the lexmark folder)

It seems to me that this has to be a bug in the filesystem access in OS X. I formatted my boot drive and reinstalled 10.2.6 cleanly. I then copied all my data from a backup back to my home directory and repaired permissions/fscked again. everything was fine. A few weeks later similar problems returned. I have verified that the RAM is fine and I have tried multiple HDs so this is not a hardware issue. If I don't do anything on the system files will not become corrupt, but whenever I download large files after a few weeks I see these issues return.

System specs:

PowerMac G4/533, 1.5GB RAM, 2 120GB HDs, Radeon 8500, Airport, All SW updates, Apple Keyboard & MS Mouse

Software used for downloads: Safari, BitTorrent, IRCle, Mail.

root is disabled, permissions are fixed, fsck reports no errors.

Has anyone else ever seen anything similar? or know anything that can be done about it. Would UFS fix this? Any idea if the filesystem is implemented better in Panther?

For now I'm using a PC for most of my internet apps and I really don't like it, but I can't afford to spend so much time troubleshooting OS X right now.

I'm under the assumption that without me entering my Admin/root password NO app should be able to damage files outside my home directory and NO copy operation should EVER cause a kernel panic even if the file is corrupt.

Any ideas?

[pat++]

You are absolutely right. Nothing *should* ever cause a KP. There is problably a bug somewhere... did you open a bug to Apple with the KP log so that they can fix it?

Did you try to enable journaling ? maybe this can help....

[NewOldbie]

This sounds like the same problem I've had on my 450 AGP G4 under 10.2.4. I posted a message about it two weeks ago but no takers. I don't know as much about OS X/unix as you do (just started looking into Unix yesterday) so please keep us posted.

My problem: Over the last 6 months I would get random file corruptions (from JPG files copied over from my digital camera to applications to system files (last night Diskwarrior 3.0 died and I had to reinstall from my CD).

I thought it might be something in my SCSI chain (DDS3 tape drive, 3rd party 8x CDRW, Jaz 1GB, along with the build in DVD-RAM drive of the G4), so I bought a 250GB firewire drive from LaCie two weeks ago and installed a fresh copy of 10.2, updating all the way up to 10.2.6. Well, software update refused to go further than 10.2.4 (something about an error prevented the operation from continuing). So I was stuck.

Having just bought a new Al 17" last week, I thought I'd try it one more time. I installed a fresh 10.2.6 from the software dvd that came with the 17 on my firewire drive while it was hooked up to the G4. The sucker crapped out on me twice. It was not until the third install attempt that the software was successfully installed. Then I go on to install all my crucial software (Photoshop, Indesign, etc.) I get 2 days use out of it and I see file corrpution again.

I can't even run Retrospect 5.0 to do a full backup of my drive. It quits on me after about 10GB.

Right now I'm on my 17 and am at a loss to what causes this problem. EVEN IF MY SCSI CONTROLLER/CHAIN/TERMINATION has failed somewhere, it SHOULD NOT AFFECT THE FIREWIRE DRIVE!

I'm guessing its a cable issue or something wrong with the I/O controller on my G4.

BTW, I've run the firewire drive on the 17 flawlessly. I suppose I can try hooking up my SCSI chain to the 17 but how the (*&#!@@^&$%@# do I do that without going to the PCMIA slot?

Sorry for the long post, this has been very frustrating for me.