Western Digital WD20EADS and TLER

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VanFanel89

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Howdy all,

My stupid ass bought some WD20EARS drivers which do not have TLER support required for proper RAID5 operation. Yeah, silly me :|

I have the chance of replacing them with a WD20EADS drive however, I need to know which drive revisions support TLER versus which do not and I am having the darnest times finding that info (cuz I don't want to have to exchange the drives again). I know, so far, that the WD20EADS-11R6B1 will not support it (has new Advance Format firmware)...

Does anyone happen to know this info?

Thanks!!!
 
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Newer EADS may also have TLER disabled in the firmware... it's a roll of the dice from what I found.

The hitachi drives would be nice problem is that even though you can enable the error correction timeout on their drives too, once there's a power cycle - the setting is lost.
 
VanFanel89 said:
The hitachi drives would be nice problem is that even though you can enable the error correction timeout on their drives too, once there's a power cycle - the setting is lost.
Click to expand...

It's not a problem since you don't need to enable that setting in the first place on Hitachi's. WDTLER has created the myth that every drive needs a 7 second ERC timeout or they'll drop from arrays like flys. Not so.
 
If you need TLER, you're going to have to buy the RE series drives..

Even if you get lucky and get a new EADS drive that you can turn TLER on, if you
ever have to RMA it, chances are the one you get in return won't.

Been down that road before..
 
odditory said:
It's not a problem since you don't need that setting in the first place on Hitachi's.
Click to expand...

Has it ever been determined why the Hitatchi's do better in RAID even though they do the same type of error recovery?
 
Just got a bunch of WD20EADS's in last week for this specific reason. All of them took a TLER without an issue.

Device Model: WD20EADS-00S2B0
Firmware Version: 01.00A01
 
Maybe all the moaning and groaning we did actually did some good?

WD replaced 5 of my WD10EADS drives with RE drives because the drive I got back from RMA didn't support TLER.
 
odditory said:
It's not a problem since you don't need to enable that setting in the first place on Hitachi's. WDTLER has created the myth that every drive needs a 7 second ERC timeout or they'll drop from arrays like flys. Not so.
Click to expand...

Actually - it's not a myth; my WD20EARS drives did drop out of the array like flies :(
 
VanFanel89 said:
Actually - it's not a myth; my WD20EARS drives did drop out of the array like flies :(
Click to expand...

What he meant was WD is trying to make is sound like ALL drives from EVERY manufacturer need it, when for the most part, only their drives do. Its not so much a myth as FUD
 
OmegaAvenger said:
What he meant was WD is trying to make is sound like ALL drives from EVERY manufacturer need it, when for the most part, only their drives do. Its not so much a myth as FUD
Click to expand...

Thank you. :) Close enough. As I've repeated in other threads (and I think I'm done now because what's the point anymore), I think setting the TLER timeout value to 7 seconds on WD drives only *masks* what is really some other incompatibility between WD drives and raid controllers. I say that because otherwise healthy, brand-new WD drives simply aren't going into a deep error recovery cycle within an hour of being attached to an array controller, and subsequently getting dropped from the array. The real cause has got to be something besides an actual error recovery sequence - more likely its some other internal operation that a 7-sec TLER timeout setting also aborts when it takes too long.

Some might say "who cares as long as the WDTLER tool fixes the incompatibility" which misses the point. Because no one bothered to question WHY the drives were dropping from arrays, and everyone it assumed it was about error correction, the assumption spread that every make and model of harddisk needs a TLER/CCTL/ERC timeout.

I realize people have reported "yeah but my Seagates, Samsungs, or XYZ brand dropped too" but every situation is unique, with many variables, and not necessarily caused by the absence of a timeout value. Example a couple years ago I experienced both WD and Seagate drives dropping from arrays within an hour of connecting them, and later determined the culprit to the a problematic integrated expander chip found on Adaptec 5 series and Areca 1680 series cards. Plenty of threads sprung up with people blaming the TLER issue, I was one of them.
 
Hrm... in that case, what's a good drive that is known to remain solid in arrays? Hitachis? Samsung?
 
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