I have this strange problem. When I try to read off of an IDE drive a file that is large (over ~200 MB or so) the system resets. Writing causes no problems at all.

Here is a command that I am running when system resets: rsync -a -v --delete --update /storage/removable1_backup/ /storage/removable1/

System also resets when I try to copy files using Samba.

The drive that is being read is /dev/hdd1

Here is some information about my system:

If you have an idea about what is going on please post it.

Please point me to a log file (/var/log/messages?, too big to find anything) which would contain the crash information.

See what happens when you disable DMA and repeat the experiment.

I think you have a power supply problem. I suggest buying a new power supply and do not be cheap. The brands that I suggest are Eneramax, Power & Cooling, and Seasonic.

Interesting suggestion, I will look into that. However, what does that have to do with copying (reading) big files? I tried copying (reading) a series of (relatively) small files (for a relatively extended period of time) and the system stays up. Also, writing files doesn't cause the crash.

Please note, I tried copying locally and over the network (Samba, SSH). All methods show that writing does not cause the problem.

Possibly a memory problem. I would run memtest86. Run it for a couple of hours to really get a good feel for it. I had one dimm that would not show a problem until at least an hour went by.

Power supply problems can cause all kinds of strange problems. I would probably install lmsensors first and see if you are getting any voltage variation(any variation of .2 or greater is a BAD sign). While actual voltage may be important, IMHO it is the variation that really creates problems. If it is a power problem do not screw around with cheap power supplies. Seasonic is good.

This hasn't crashed the system so far (it is still in the process of copying) but it's too slow, obviously.

What does this suggest?

After I have turned off DMA the system has been stable (but slow). What could be the reason for this (DMA-related failure)?

Probably VIA VT82C586A/B/VT82C686 or the IDE controller has a glitch. The glitch can be minimize by changing a few registers using setpci. Sorry I do not remember what registers to modify. Another way to fix it is try upgrading the BIOS. If that is too hard, include noapic and/or noapci or apci=off at the boot loader.

With out knowing how many hard drives that you have in LVM2 or EVMS. I still think your power supply lost its grunt or does not have any grunt to start with. Four hard drives can consume a lot of power.

Another cause is heat. The chipset or procssor could be over heating.

Thanks for the info.

I ran memtest86 for three hours but with no errors. I will try another power supply and other suggestions. Thanks a lot.

I have just tried another power supply (which I know worked with 4 hard drives and a CD-Rom). It did not make any difference at all. The reset still occurs with DMA enabled. I will try some of the other suggestions but this seems hopeless to me. (boy, do I want to beat up the person who built this server).

Go to cyberguys.com and buy the post code board.