Gspeed ES Pro RAID keeps disappearing from Mac, have to re-initialize!

[Jesse Schluntz]

Thanks for the advice. Would’ve gone with another model had I known ahead of time. Will do in the future.

G tech has awesome external drives up to a point, but as for RAIDs, I’m moving on.

jesse

[Alex Gerulaitis]

I usually agree with Rainer – but not in this case. I worked with G-Tech since they were called Medea. While not all G-Speed products were absolutely stellar (HiPoint controllers aren’t exactly top tier), G-Speed eS Pro is so simple, it’s hard to find fault with it. It’s an external backplane with a 3rd party controller (ATTO R680), and it’s nearly guaranteed that if you take the drives out of the eS Pro and put them in a different (but similar technically) enclosure while using the same controller, the issue will not go away.

The issue is about 99% between the OS and its file system, ATTO controller, its driver and configuration, and the drives. The box itself is highly unlikely to be a major player in it. It’s also supported by thousands of eS Pro boxes being used out there 24/7.

(Sorry to disagree with you Rainer. I may end up eating my words. :))

[Rainer Wirth]

Alex,

I’m not sure either, because this problem is so strange, and Jesse really tried nearly everything, that our expertise comes to the end of try and error.
I have got no new, good or better idea to work around it. Except that I’m a friend of expensive raid products, because to me I’ve never regretted the most expensive arrays. Less hustle, better reliability, longer use, in the end cheaper.

cheers,

Rainer

factstory
Rainer Wirth
phone_0049-177-2156086
Mac pro 8core
Adobe,FCP,Avid
several raid systems

[Rainer Wirth]

One last little thing!
How did you format the array? OSX with journaling or without? Arrays should always be formatted without journaling!

cheers

Rainer

factstory
Rainer Wirth
phone_0049-177-2156086
Mac pro 8core
Adobe,FCP,Avid
several raid systems

[Jesse Schluntz]

Honestly can’t remember. It’s been quite a while. All I can tell you is I was talked through the process by both ATTO techs (the raid controller) and G Techs. Neither method worked. Had nothing to do with anything other than a bad design by G Tech unfortunately.

[Joe Church]

I am having the exact same type of issues on a Windows system with a desktop RAID solution over eSATA. I can tell you with a high level of confidence that your issues are caused by the same thing as mine. Its your drives. I have done a ton of research over the last few days because I wanted to get cheap 3TB SATA drives to use in my desktop RAID enclosure. I got Toshiba drives, decent but not meant for RAID or NAS. You said your drives are WD Blues, which are also not meant for RAID or NAS solutions. I can almost guarantee you that if you run out and grab some WD Reds or some of the better Seagate NAS drives, you will not have this problem. Desktop class drives don’t handle error correction very well and if the drives you use aren’t fully compatible with the RAID controller and its required feature set in the drives, then you will have these kinds of issues. You don’t need to replace your entire RAID, but you do need new drives. Unfortunately the drives are one of the most expensive parts. I’m in the same boat.

[Chris Murphy]

The eS Pro data sheet says they come with SATA Rev. 3 enterprise drives. They will have the proper SCT ERC setting for this use case. Given the cost of the drives and the effort to go with SAS, I’m slightly perplexed with the use of SATA drives. But I doubt that’s related.

The recurring theme is that the failure happens near the end of file copy, regardless of the sequence of the source used. So I’m thinking of three possible causes, only one of which is hardware related:

a.) Apple has a rather significant file system bug on their hands, in 10.7.4 (at least), that causes it to face plant some time shortly after 20-25% free space remains on a 12TB volume. Possible. Seems least likely of the three.

b.) Firmware/driver bug. Something is being translated wrong between physical device LBAs and the logical LBAs sent to the file system. File system is writing, writing, writing, and then upon reading some bit of file system, it’s been damaged – per the very first post on the thread. Buggy firmware is a significant cause of silent data corruption at the drive and controller level.

c.) One of the disks has damage, possibly conveyance related. If a large number of sectors have somehow gone bad due to damage, they are automatically substituted by drive firmware with reserves. But if all reserves get used up, the drive must report a write error the very next time a persistently bad sector is written to. Which would be pretty much in the same place every time. The controller tends to collapse the array when this happens.

a and b. are easy to test. Borrow a completely different brand of SAS controller and repeat the test. If it fails, it’s a file system bug. While the ATTO R680 has a linux driver, a linux based test with XFS or ext4 while interesting, presents an ambiguity: maybe it’s a driver bug.

c. Run smartctl -x on all of the drives to see if there are or have been bad sectors (goes by various names). Ideally the drives should have extended offline tests done regularly. And they should have had the conveyance and extended offline test run before being put into production.

But in any case, it’s a nasty bug.

[Jesse Schluntz]

Interesting Joe.

This point was never raised during my entire experience. I don’t know exactly what kind of drives I have in this RAID, and am scared to pull one to find out, but according to G Technology they are SATA III Enterprise class, but I’m no expert.

thanks for the info. I’ll definitely consider it when I get my next RAID.

[Jesse Schluntz]

Thanks Chris.

The drive hardware wasn’t the issue. G Tech sent me an entire new raid to help troubleshoot.

As for all the other tests, they would take over a week so I can’t get into those. I’ll just buy a solid RAID next time. By the way, I wasn’t aware the G tech raids weren’t solid until this happened. My first time around the block with a raid.

If anyone else reads these threads, I’d just be stoked to get a short list of the best raid systems that won’t break the bank. thanks!

[Chris Murphy]

an entire new raid

Does that mean a new enclosure? Or new enclosure and new modules (drives)?

I can’t get into those. I’ll just buy a solid RAID next time

Unless someone with different hardware can vouch for successfully filling an HFSJ/HFSX volume to 90+% used, on 10.7.4 specifically, there isn’t a way to know that merely buying a different product would have avoided the problem.

While a file system ought to tolerate being filled to 100% of its own reported capacity, experience tells me that file systems start to do weird things when they get beyond 90% capacity, and therefore I tend to avoid that situation unless I’m testing. I’d guess that the user experience of 90% full file systems is comparatively rare, so this may not be heavily tested in real world scenarios.

But only because of the error -36, which is not an out of space error but some kind of IO error, leads me to think more likely it’s either a firmware or driver bug. A full set of kernel messages might be more enlightening.