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Adam Wunn Author

Level 1

9 points

6TB drives won't mount after restart in Mac Pro 2012

The problem manifests itself when a 6TB HGST drive does NOT mount on the desktop nor appears in the Disk Utility after a reboot. The ONLY way I have figured out how to work around this problem is to shut down the computer and the open the case and slightly pull out one 6TB hard drive (i.e. enough to release it from the SATA connector on the logic board) and then push it back in. At that point, if I boot the computer any and all 6TB HGST drives installed in the computer will appear on the desktop until I restart the next time. I don't have to remove each and every drive to make them all appear, just one.

When I first experienced this issue, I assumed it was a hardware problem with that one computer, but I have now experienced it again with a different computer at the different company and with a 6TB HGST drive from a different production batch. Now that I have two data points, I want to test this configuration on other computers to see if I can figure out if it is more widespread than the existing two machines.

The similarities between the two machines are more than the differences. They are both Mac Pro 2010 5,1 models at their core, but they are also both the 2012 variant that was a slight upgrade from the 2010 model. They both have the shipping EFI firmware (which is the latest for that model). They both have 20GB of RAM and they both run Mac OS X 10.8.5. One machine is used for graphic design and the other is a server. They also both have more than one drive slot being used. The one machine that is the server have four drives. Two are 2GB drives used as the boot partitions. The last two are 6TB data drives. The other machine that is used for design has two 2TB drives for booting and backup and one 6TB drive for Time Machine (the fourth slot is empty). In both cases the 2TB drives are Toshiba drives (using the HGST derived manufacture process). Also in both cases the two 2TB drives are in slot 1 and 2 and the 6TB drive(s) are in 3 or 3 and 4. They both have ATI Radeon 5770 cards. Both are plugged into Ethernet networks and do not have wireless turned on.

There are some differences too. The server has a number of external RAID boxes connected via an ESATA card. The other computer has nothing in the PCI-E slots. The server has an after market replacement DVD and the graphics machine has its stock DVD drive. The server machine runs OS X Server.app.

I have a number of resources at my disposal so I plan to do some further testing. That said, I don't have everything to be really thorough and would love some help from others whom are either experiencing this or just want to help. Here is what I don't know and would like to test.

I have in my world Mac Pros that I can test at different customer locations. I can test a 1,1 easily, and I can also test a 3,1 and 4,1. I have those all available in my direct control right now. What I don't have is a 5,1 2010 model, but I can borrow one to test. I can also procure another 6TB HGST drive. What I don't have is a WD 6TB or other brand. I would love to know if this is specific to HGST or if it is a general problem for 6TB drives, Also, for that matter, I would love to see if this happens with 5TB drives. Has anyone else installed a HGST or WD 6TB and had mounting problems?

It would also be great to know if this issue is independent of OS. I plan to test 10.6, 10.8, and 10.10. Of course on the 1,1 Mac Pro I can't test past 10.7. I also would like to know if it matters that a 2TB drive is present and even if that drive is a Toshiba or other brand and even the quantity of drives and their slot position. I hazily remember trying to move drives around in slots when I first encountered this problem. I also wonder if different models of the 6TB drive may behave differently (i.e. NAS versus Enterprise).

I plan to post my results when I am done with the testing.

Mac Pro, OS X Mountain Lion (10.8.5)

Posted on Jul 16, 2015 11:26 AM

113 replies

Adam Wunn Author

Level 1

9 points

Aug 12, 2015 1:24 PM in response to Grant Bennet-Alder

In my case ALL of the affected machines use 7,200 RPM hard drives to boot from and do not have any SSD drives installed. I have tried different combinations of capacity of drives and brands and all that really seems to matter is if the HGST 6TB NAS drive is installed. In that case, the problem always occurs and no other configuration change seems to make a difference.

Adam Wunn Author

Level 1

9 points

Aug 12, 2015 2:06 PM in response to sinoue

Here is my latest report on my tests and results.

I tested the HGST 6TB NAS drive in a Mac Pro 3,1; a 4,1; and a 2010 5,1; and a 2012 5,1.

In Mac OS X 10.6.x the drive mounted properly from a cold boot and when restarting. I could also use the drive as a data only drive or a boot drive without issue. I was able to reproduce this result with the 3,1; 4,1; 2010 5,1; and 2012 5,1. I chose not to try this in a 1,1 Mac Pro since, I knew that drive worked properly with 10.6, the test seemed superfluous.

In Mac OS X 10.8.x, the drive mounted properly from a cold boot and when restarting only with a Mac Pro 2008 3,1. The drive would not mount after a restart, without first shutting down the computer, on the Mac Pro 4,1; 2010 5,1; and 2012 5,1. I also tried using it as boot drive on all of the computers with the same results. The interesting thing is that what I saw may dispel the idea of this being a rotational unit attention ready issue. The grey apple would appear when restarting from the 6TB drive AND the progress bar would start to load, but eventually the grey apple logo would change to the circle with a slash that appears when drives are failing or the OS is corrupted. If I simply forced the power off and then immediately booted the computer again, all worked well and the OS on the 6TB booted successfully.

In Mac OS X 10.10.x the results were the same of the 10.8 test. The Mac Pro 3,1 worked flawlessly, while the 4,1 and both 5,1 models failed with the expected pattern to both tests as a data drive and a boot drive.

I purchased a HGST Helium drive (the more expensive enterprise version and repeated all of the same tests and the drive worked perfectly for both booting and for data on all of the computers tested. So as suggested earlier in this thread the Helium is compatible (though more expensive) and a good alternative to the NAS drive to work around this problem.

To summarize, the Mac Pro 3,1 works without issue with the 6TB NAS and the Helium drives in all of the tested OS versions. The 4,1 and both 5,1 models are compatible with the Helium drives but they do not work properly with the NAS drives in 10.8 and 10.10. Conversely, if those same machines are running 10.6 the NAS drives work fine.

So this does indeed seem to be a driver issue on Apple's end or a firmware issue on HGST's end. My gut says it is Apple's problem since the drive works fine with an ancient OS and doesn't work with newer versions. I am pretty sure that I once read something to the effect that with the Mac Pro 4,1 Apple changed a controller for the SATA system and is using a newer class of driver. I can only speculate as to whether that is at least part of the cause of this issue.

For now I am satisfied that I have a answer that is good enough to explain what is happening and how to work around it. I am not holding out any hope that this problem will ever be resolved, but at least I have an answer that will work for my customers. Thank you to everyone who helped with this issue and for your insight and support. At the beginning, I was afraid I was the only one who was experiencing this issue.

Adam Wunn Author

Level 1

9 points

Aug 12, 2015 2:07 PM in response to Grant Bennet-Alder

I experienced the same issue with hard drives though so having an SSD in the mix doesn't seem to make any difference.

The hatter

Level 9

61,001 points

Aug 12, 2015 2:10 PM in response to Adam Wunn

I have read of people using WD NAS (Red) drives, though I would think only suitable for a NAS box and hardware RAID, not internal. Mostly it was to save money as the prices on other 6TB drives can be very much higher. But the firmware for drives designed for RAID can be customized and not work in other environments. Not really legacy or not issue.

Adam Wunn Author

Level 1

9 points

Aug 13, 2015 10:29 AM in response to The hatter

Yet NAS drives have always worked for me in any other environment and indeed work here too with older Mac Pros. These seems more like a bug than intentional firmware modifications. All of the other capacity HGST NAS drives work with these machines. The only way a firmware change makes sense is if they realized there was some inherent incompatibility with the newer "old" Mac Pros and intentionally disabled support. But if that were the case, why not just come out and say that in the first place? My sources at OWC tell me that HGST was not aware of the issue until it was reported by OWC, myself, and several other end users. If they were not aware of the problem, it seems unlikely to be intentional. Either way I don't expect a resolution.

sinoue

Level 2

236 points

Aug 26, 2015 2:09 PM in response to Adam Wunn

Adam - Great test results. Thanks for going the extra mile!

I can add to your conclusion that the HGST NAS 6TB compatibility issue on restarts is Apple's problem.

I tested removing the OSC Accelsior S PCI-e to SATA 3 adapter and confirmed the problem happens without it.
I tested booting Windows 10 under Boot Camp and confirmed that Windows 10 and Windows 7 restarts have no problem seeing the secondary HGST 6TB hard drives (booted from both the Samsung 1 TB SSD and a HGST 4TB).

I'm wondering if someone who is testing El Capitan can confirm the restart not mounting HGST 6TB NAS hard drives issue still exists and can log a bug for Apple to hopefully fix.

Sep 17, 2015 12:19 PM in response to sinoue

I see Toshiba have announced a 7200rpm 6TB drive that doesn't cost the earth like the Helium drives - the X300:

http://www.storagereview.com/toshiba_announces_new_highperformance_hdds

I'm considering this model to replace the 6TB NAS (moving that to external for clones) but has anyone tried one of these yet?

I'm hoping the restart issue won't be present and that the screw positions are preferably OK for the drive sleds.

Oct 7, 2015 12:45 PM in response to Matthew Wilson5

OK I couldn't find any reviews at all on this drive on the pre-release announcement articles so I decided to be a guinea pig and buy one of these 6TB disks.

The bad news is that it doesn't have the central screw holes so I couldn't use it in the drive bay sleds.

instead I ended up installing this disk in the optical bay and moving the disk I had there previously to the sled.

The good news is that the Toshiba disk mounted OK on restart (unlike the 6TB HGST NAS disk) so I now have a 7200rpm compatible option that isn't at HGST Helium price (the disks we would all prefer to use if funds were no issue I guess).

Oct 7, 2015 1:16 PM in response to Matthew Wilson5

The bad news is that it doesn't have the central screw holes so I couldn't use it in the drive bay sleds.

The good news is that OWC sells a special sled for just this purpose, US$20:

http://eshop.macsales.com/item/OWC/MPRODBKTLG6/

Oct 7, 2015 1:24 PM in response to Grant Bennet-Alder

Yeah thanks, the longer I keep this machine the more likely it is I'll end up getting one of those as storage requirements always seem to grow.

Some 6TB model are OK with the stock trays though so it's work keeping a note of which ones.

Oct 7, 2015 1:52 PM in response to Matthew Wilson5

The other issue (in addition to MOVING the screw locations) is that WD in particular shortened the allowable depth penetration of the screws adjacent to the platter area to squeeze in another platter.

The risk is that you will insert the original long screws until tight, and not notice they are tight because they bottomed out before the gaskets were "snug". This can allow the drive to not stay level with the sled on insertion, and fail to align with the backplane connector.

Oct 7, 2015 1:55 PM in response to Grant Bennet-Alder

Think I read that with some of the red drives?

There could do with being a list or table of drive models and notes on each for use internally with a Mac Pro, but I guess the number of owners trying out these newer disks is probably quite small.

PRC

Level 1

83 points

Oct 11, 2015 10:35 AM in response to Adam Wunn

I too confirm this issue. Mac Pro 2012 2 x 3.06 GHz 6-Core Intel Xeon 48 GB 1333 MHz DDR3 ECC MD Radeon HD 7xxx 3072 MB

HGST or WD 4GB drives mount as expected. HGST NAS 6GB drives don't mount as expected.

Interesting, as I DO have a RAID 5 setup with 4 HGST NAS 6GB Drives which mount (as one drive of course) easily. These are in an OWC enclosure (ElitePro Qx2 Media) via USB3 through a Sonnet USB3 PCIe card. (The original Caldigit card would not work with El Capitan 10.11 or 10.11.1 beta.)

So, it is just the 2 6GB drives. I can reset the PRAM and they will mount but don't want to have to do that every time.

The drives are spinning and warm but don't mount, not even if I pull them out and push them back in. Frustrating as I need the 6GB space.

Patrick @ MacOvation

S.M.A.R.T. status: Verified

PRC

Level 1

83 points

Oct 11, 2015 12:26 PM in response to PRC

Experimenting using Tinkertool System to AUTOMATICALLY MOUNT external volumes at startup before login

THEN

Using Cocktail DELAYING STARTUP by 20-30 seconds to see if this gives the 6GB drives enough time to spin fast enough or whatever

to mount.

So far so good but only 2 restarts.

Will let you know.

Patrick @ MacOvation

Belayman

Level 1

0 points

Nov 17, 2015 10:00 AM in response to PRC

PCR - what's the verdict on using Tinkertool System + Cocktail to enable reboot with the 6TB HGST drive? Has it worked well for you? I've never used (nor heard of) Tinkertool System or Cocktail, so I have no experience with them.

I also wanted to add my experience to this thread ... my system is showing the exact same behavior as described in the original post: on a cold start, all the drives load/mount properly, but on a reboot, the 6TB HGST HDDs won't mount (they don't even show up in Disk Utility).

Mid-2010 Mac Pro 5,1

OS X 10.10.5 (SSD for boot)

6TB drives won't mount after restart in Mac Pro 2012