choosing harddrives: RAID models?

[philippp]

Hello,

having built a few SATA RAID configurations (using 3ware controllers or the like), I know that one should choose disks that are explicitly marketed as RAID disks, for instance like the WD1002FBYS RE3 "Raid Edition".
The reason is said to be that, in case of media defects, such disks would report the error to the controller, which then takes the appropriate action (i.e. recover the lost data from the redundancy data on the other disk(s)).
In contrast, ordinary desktop ("non-RAID") drives, would try to recover the error themselves, probably trying to re-read the defective sector for a longer time. This could cause the command to timeout, and the controller would mark the whole drive as defective, and unnecessarily degrade the raid array.

The smaller QNAP devices seem to use linux softraid. So the case might be different here, as linux softraid probably is optimized to deal with "ordinary" desktop drives. Therefore, it would be useless to buy expensive "raid edition" drives, compared to standard desktop drives (provided they are made for 24/7 duty).

Is that correct?

[QNAPJason]

Hi philippp,
We still recommend using Business-grade HDDs for storing critical personal and business data because these types of HDDs are typically more durable and made of higher quality for 24/7 operations. Moreover, when these HDs encounter new issues, HDD makers usually will release new firmware updates to fix the issues more quickly (chck WD2002FYPS for example).
QNAP NAS use software RAID, which monitors the RAID error recoveries based on the detections. Nevertheless, it's still better to buy RAID-certified to store your importan data.

Jason

[philippp]

Hi Jason,
thanks for your reply!
(I was asking this because a dealer recommended me to buy Hitatchi CLA332 for RAID1, stating that these disks were made for 24/7 operation, and that my other concerns [TLER, in the meantime I found the exact therm] were unnecessary.)
By "detections", you mean that the NAS will know whats going on, if a desktop drive is trying to recover on its own?

[cstork]

Hi Jason,

Do I understand you correctly that Qnap's softraids are actually better served by leaving ERC/TLER/... disabled on consumer grade HDDs like eg Seagate Barracuda LP (which I'm considering to buy ???

Thanks for all the infos,
Chris

[RedFalcon]

I am wondering the same thing as cstork in the previous post.

i have some WD Caviar drives in a RAID 5 and i havent done anything special to the drives as far as TLER goes.
Should this be changed? If so, how? the utilities i have seen online all require DOS. if there was a way to do this from within my NAS that would be much easier.

edit:
i thought i should mention that my nas has been running great for more than a year now. Maybe two? i can't remember...
i did have a case about a couple months or so ago where a single drive was removed from the RAID array. i removed the drive and popped it back it and it seemed to work great. no errors were detected, the array was rebuilt without issue and it was back up and running shortly thereafter.
is this the type of problem that should be EXPECTED with this TLER thing?