Hello, I''m using snv_81 x86 as a file server and occasional CPU server at home. It consists of one system disk with normal UFS/swap and one pool of six disks in raidz1 configuration. Every now and again the raidz file systems will lock up hard. Any access to them will block in IO-wait. Trying to reboot will lock up the system, so pressing the reset button in the only option. After a reboot everything works fine again. I can usually trigger the problem within 12 hours by doing lots of compilations in parrallell, but just leaving it alone serving files via Samba and NFS will trigger it within a couple of weeks. The problem has been there ever since I installed snv_55 on it way back, so my guess is that it''s not a systematic error in ZFS, but rather a driver problem or a hardware glitch. The trick is figuring out which of those two it is so I can correct it. I should mention that we are talking about disks, whose natural state of course are full: % df -h /famine Filesystem size used avail capacity Mounted on famine 2.7T 72K 14G 1% /famine So... 1. The root shell still works. How do I go about trying to debug things when the filesystems lock up? 2. This is a pretty well ventilated chassi, but trying to determine if things get to hot of pull too much power is always prudent. Where should I look for information on how to set up MB sensors and SMART access? 3. The pool is divided between two SIL-3114 cards flashed to the non-RAID bios version running on a single P4 CPU. Any known problems with that configuration? TIA, -- Peter Bortas