[thor17usa]

Well...the worst has happened...I lost 2 SCSI drives in a RAID 5 setup. I have 7 50GB SCSI drives setup in RAID 5 and at first one failed. I tried doing a rebuild, but that failed, so I tried doing the rebuild again and a second drive failed. I am not sure if there is something wrong with the drives physically or what...but I just lost over 150GB of data.

I wanted to know if anyone else has ever had 2 drives fail like this and what might be a good way to prevent this in the future. Should I scrap the SCSI RAID 5 and got with cheaper IDEs? I tried rebooting and nothing... I am so ******ed right now. Any help would be great.

[flixotide]

Since you're using RAID 5 and SCSI disks, I automatically assume you are using hardware RAID5, possibly with some hotswap SCA scsi based disks.

In that case, I would ALWATS recommend to have a disk set as hot spare, for rebuilding to happen automatically.

I've had 2 disks in a mirrow quit on me once, but never had a raid 5 failing on me like that.

Could you give some more details to the setup? disk types, drivers, raid controller, O/S etc.?

Cheers, Flix

edit: for important systems I would still recommend running RAID5 on SCSI setups. I have a series of NAS boxes based on sata raid 5 arrays, and the rebuilding takes ages compared to scsi machines, and the sata raid boxes literally come toa grinding halt during rebuild, where SCSI keep heads up.

[thor17usa]

The raid controller is an AMI MegaRAID 438 with 3 scsi channels and the drives are 50GB Seagate ST150176LC 80pin SCA hotswap drives. I have never had problem like this in the past...so it seems rather odd that 2 drives would fail at once. I am running Windows 2000 Server. The RAID 5 is really just storage and the OS is on an IDE drive. I went with RAID 5 for data protection...but I guess some went wrong elsewhere to cause this problem.

I am starting to think that IDE will be cheaper to deal with.

[Xaotic]

Root cause analysis can be a pain. It doesn't help that these are 4 year old Ultra2 SCSi drives and may have been abused by past owners. As far as causes, it may not be the drives themselves. It could also be cabling, backplane, controller or even the power supply.

RAID, though it can be redundant, is not a backup. There is no substitute for a good current backup. The more complexity that's added to a RAID subsystem the slower the performance is and to some extent, the more likely it is to fail over time.

IDE will be cheaper to run, both in initial outlay and running costs. You will still always need a backup.

[thor17usa]

What you recommend for and IDE setup? I am thinking about getting two 250GB 7200RPM IDE drives and setting them up in RAID 1. Then if I get some more 250GB drives I will setup RAID 0+1 (RAID 10). I will probably just stick with IDE cause SATA is expensive right now.

[Xaotic]

I remember the lowest price per GB is either the 120s or 160s, so you may want to look for those. RAID-1 is fairly safe and for a file or game server, I wouldn't switch to a striped mirror configuration. If this is your usage pattern, you will probably be network bound and increasing disk performance is probably overkill. If the data on the server does not change frequenty, 24/7 uptime is not required and newer versions of files are replaceable, consider dropping the RAID and just temporarily connecting the drives that would have been used for mirrors for backup and storing the copied drives in another location.

[thor17usa]

For the most part the server is used for storage. I just upgraded it to dual 1ghz cpus, so I plan to start doing video encoding. I will be converting AVI files to MPEG-2 video for placement on DVDs. I am using Pegasys TMPGenc Xpress 3.0 for my encoding.

The new mobo has ATA/100 so that should be enough for my needs, right? The board will support up to 8 IDE devices because of the onboard RAID (0, 1, and 0+1) but I am thinking about just loading it up with drives and fargoing the RAID setup.

Ever attempt to bring the old SCSI array backup keeps failing, so i am starting to think that either the card, cables, or drives are bad. It could also be the power supply because there are 7 50GB SCSI, drives, 4 60GB IDE drives, dual p3-1ghz. The might be too much for the dual redundant PSU. Any more suggestions?

[flixotide]

Seeing as you would also like to do some encoding, i would still stick with the SCSI setup for best performance.

The AMI megaraids have alwayys had a good reputation with me, so i can't shoot there. BUT I have had a lot of problems with poor scsi cabling, so they might be worth checking out.

And apart from that, all i can recommend is excellent airflow and airconditioning where you have your server. Especially file servers working a lot need loads of cool air for those hardworking disks. Cleaning the SCA drive bays and backpanel is also a good way to ensure they are kept cool.

Cheers, Flix

[thor17usa]

I will take a look at the connections and setup later this week and probably do a format on all 7 drives to check for any bad sectors. At this point I cannot afford to replace any SCSI hardware...so I am starting to think that I will need to switch an all IDE setup. It won't be that bad because my motherboard can support 8 IDE devices. I am also looking at a new case and PSU...so that should also help.

Someday when I when the lottery I will go back to SCSI, but for now I need to take the cheaper route. Thanks for all you help. Let me know if you have more suggestions.