Remember to regular scrub your RAID arrays! Usually, you have to manually initiate it from the RAID card web gui, but for the Areca 1680 series, you can schedule RAID set scrubbing.
Scrubbing is ESPECIALLY important for RAID 5 arrays, otherwise you very likely will have a double-drive failure, which is, of course, fatal for RAID 5.
Robotbeat - does RAID scrubbing effect performance at all? Should I only do it on a weekend or can I run it anytime? I have an Areca RAID Controller as well. I never even knew about this.
It greatly affects performance, so only run it on the weekend. You don't have to unmount anything. I didn't really realize this until I started thinking about the Bit Error Rate/Nonrecoverable Read Errors per Bits Read ratings of different hard drives. I ran the "Volume Set Functions->Check Volume Set" RAID scrubbing utility on a couple of Areca RAID systems we have. They are 10-drive RAID 6 raid sets (8+2), so rebuilding is usually pretty safe, but I figured I should try it anyway. No errors were found. Either that means that there were no errors found on all the drives or that the verify operation was able to correct any data corruption. Both of these systems are about two years old.
The Areca RAID manual suggests running the volume set verify once a week. In the older non-SAS RAID cards, you have to manually do this check, but in the 1680 series SAS RAID cards, there's a new option under "Volume Set Functions" to "Schedule Volume Check." I haven't started this on our systems in the field that have this newer card, yet.
The only thing about verifying so often is that it might wear out your disks a little faster than otherwise, although your data is safer. On my 10-drive RAID 6 sets with 500GB Seagate Barracudas, verifying took about 3 hours with about 500MB/s of verifying (including the parity data), which is about 50MB/s per drive, about as fast as is realistic for these drives to go sustained.
Do all RAID cards have the option for RAID Scrubbing? I have an HP server with a HP P800 controller in it and I don't think it has an GUI or WebGUI to do anything on.
One thing that I am still uncertain of and would like some info on. What RAID levels need scrubbing? Does it apply to all RAID levels? I have never looked into it in depth and currently my google fu is failing me for finding info on scrubbing any RAID level other than 5/6.
Well... You may have errors on any sort of RAID array, or on JBOD disks. It's just that there's nothing you can do about it with RAID 0 or JBOD, besides just going to a backup. I'm pretty sure you can do a volume set verify on any RAID level that has redundancy (RAID 1, 3, 4, 5, 6, 10, etc).
That is what I was thinking, that any RAID level with a parity runs the potential for some problems. The scheduler is nice, but doesn't let you set a day of the week to implement it. Which kinda sucks.
If you can get to the card's CLI (command line interface), you can make a batch script in windows that will scrub automagically using windows' scheduler. Probably a way to do it in linux, too.
Whizz Kid
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