Multiple hard drives crash

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Posted by Reround, 10-29-2014, 10:21 AM
I've tried serving files from two hard drives multiple times and the server always ends up crashing. I have tried RAID 0, mhddfs and the simple solution of assigning all the space of the first hard drive at / and mounting the second hard drive in public_html and have Apache serve files from there (I think this option was the worst one as Apache's CPU load skyrocketed). I don't think the problem has anything to do with Apache, but instead with the filesystems. Should I give ZFS, AUFS (kernel patch not FUSE) a shot?
Posted by (Stephen), 10-29-2014, 11:08 AM
RAID0?! never use RAID0 on anything that is even of minor importantance. RAID0 is NOt RAID at all, it is a stripe for performance only. It at least doubles your chances of failure!
Posted by Reround, 10-29-2014, 11:37 AM
Well, which filesystem would be suitable for combining two hard drives into one mount point (pool)?
Posted by Stream101, 10-29-2014, 12:32 PM
You need more drives. I wouldnt consider anything less than RAID5. One of the drives is used for redundancy. Wiki actually has a great post on different RAID types: http://en.wikipedia.org/wiki/Standard_RAID_levels
Posted by NoSupportLinuxHostin, 10-29-2014, 02:35 PM
Never use RAID0. With RAID0, you lose all of your files the moment one drive fails. Use either RAID5 or RAID10. RAID10 easily offers the best performance, but will cost more than RAID5. Also, consider using SAS drives instead of cheap SATA drives. SATA drives will sometimes generate a drive failure during heavy IO loads simply due to timeouts, even when the drive has not actually failed. Enterprise SATA drives are better than cheap SATA drives in this regard. SAS drives work best, though.
Posted by Reround, 10-29-2014, 05:24 PM
I would however prefer not to run RAID at all. Would it be possible to somehow mount two hard drives in the same folder?
Posted by Stream101, 11-03-2014, 05:06 PM
You could you a symlink, however running a production server without RAID is terrible.
Posted by Andei, 11-03-2014, 05:24 PM
If you're serving up files then I'd suggest going for RAID10, which has both redundancy and performance.
Posted by RRWH, 11-03-2014, 06:39 PM
RAID 1 - You are serving files - at least with RAID 1 your read performance (which is important on a file server) would be using both drives, as well as providing redundancy.
Posted by BitronicTech-Bryan, 11-03-2014, 10:58 PM
RAID 1, 5, 10 are the way to go, RAID0 is a terrible idea.
Posted by HostXNow_Chris, 11-04-2014, 04:48 AM
Best to use RAID 1, 5 or 10.
Posted by (Stephen), 11-04-2014, 11:29 AM
RAID5 is really not a good option either guys, it has a very high failure rate both in theory and in reality, and is very hard to fix if it fails. RAID1, RAID10, RAID6 (hard to repair but at least can sustain 2x failure, needs dedicated cpu/hardware raid to work well), or some type of ZFS with raid like functions are the way to go.
Posted by XenNodes, 11-07-2014, 10:33 AM
raid1 for os, raid 5 for data etc
Posted by Crypracks, 11-09-2014, 02:40 AM
Raid 0 -A Big NO. Raid 10 or Raid 5 or at least a Raid1 would be suggested for both performance & redundancy