Q: Yosemite ejects external drives

I reported this issue over a year ago. External disk drives are ejected on awake from sleep. Like you I find it difficult to believe it's an ongoing issue.

I have to unplug my LaCie dual drive's Thunderbolt cable 2- to 3-times per day. Ridiculous this day and age.

Maybe should abandon Thunderbolt for USB3 like the latest post suggests...

= Martin =

However for me, since I'm now on Yosemite latest version, the only drive that currently does this ejection is my Time Machine drive that is USB3.  The Thunderbolt 2 and drive that is Firewire 800 connected to a Thunderbolt adapter connection, no longer eject.

saidts wrote:

 

After perform a Clean Install of OS X El Capitan this problem disappear.

I started to have it since clean installed El Capitan.

Had this problem sometimes in the past with Yosemite, it was gone since a while.

The problem seems to be related with Thunderbolt, but here is a weird thing:

I have 2 WD external drives with their own power adapter, and one bus powered. The three drives are all chained via Firewire 800 and attached to a Thunderbolt display. The Macbook pro is attached via Thunderbolt to the Thunderbolt Display.

I'm having the weird ejections on the two drives NOT bus powered. The third one, which is also the last one in the FW chain, doesn't get ejected.

Here's another strange thing: I'm using these three drives as a JBOD, no softRAID, and I'e made different partitions on them. Some are also FileVault encrypted.

Some volumes don't get improperly ejected, and I get a message in finder on wake-up for those saying something like "Drive WD-xxx couldn't be powered off because it's still in use".

I have about 8 external drives for various projects and back up (and anxiety when one fails). 

The WD 1.5 TB HDD 1021  and Lacie quadra 1TB are the only ones that eject regularly.

My Lacie Rugged and other WD My Book etc. do not eject ever (knock on wood). 

All 8-10 drives are daisy chained through USB hubs to my computer.  I'm still with Yosemite.

I have this many external drives just because of such problems -- drives not mounting in the past, or ejecting.

Does anyone recommend doing online storage instead??

Thanks!

I replaced my old iMac with a fully loaded mid-2014  Macbook a year ago. I had been using a WD hard drive since 2010. For many months Time Machine has been intermittent; there is a window that says "disk ejected improperly". I believe the Apple reps have done all the appropriate steps to resolve the problem. Per their instructions I have replaced the WD USB cord. Last week I purchased a replacement WD MY Passport. The problem persists. I have recently searched the internet and see no problems identical to my own, although a similar one was resolved by deleting Spotlight. A few days ago the senior rep at Apple sent the problem to Apple engineering. They want me to try a hard drive from a different manufacturer {other than WD}. Is this reasonable? Any thoughts?

Updates: after having un-installed the WD software (Smartware) through its un-installer (which also deletes stuff installed in LaunchDaemons as well as kernel extensions), the problem seems to be gone.

Apple just called and said messing with Spotlight was a real bad idea. They will send me a new aux H/D at their expense. We will see what happens.

I have about 6 external drives currently daisy chained with my MBP --  the main ones that were ejecting like this were all plugged into the same power source strip.  I'm curious to see what happens if I replace that power source.  Also, the Lacie rugged drives have NEVEr ejected like this.

Depressingly I found this on another thread of a similar topic. Which basically says it's going to be luck, circumstance and device specific whether you get this situation or not. Technically you should be having the problem all the time. This is from an engineer at Sonnetech who actually sounds like he knows what he's talking about (and for USB/FireWIre I'm assuming we include include Thunderbolt 2).

The error messages are unavoidable:

As part of the sleep mode, and by design, the Mac computer cuts all power to the PCIe cards.  This causes a reset of the USB 3.0 and Firewire ports on installed PCIe cards when the power returns.

The drives will automatically remount, and the O/S backs-up data files that are open before the computer enters sleep, but the error message will still appear because OS X detects that the interface has been re-set.

Unfortunately the only way around this is to have the screen power down, but do not allow the Mac to enter power-off sleep mode.

Not that i can say 100% without a doubt, but I was on Yosemite and late this year, this issue started with my external drive that I had partioned into 2 spaces.  Both partitions are used for Superduper backups. I don't remember if my Time Machine drive would eject per this issue during that time period. 

I don't recall doing anything, like adding a new drive, or changing cables, etc.  All that I believe could have happened is I installed an OS update and sometime after this issue started. 

Now I'm on El Capitan.  I feel that by that point in time, both the Superduper drive partitions and Time Machine drive was ejecting. 

Currently only the Time Machine drive will eject.  The other drive no longer ejects.  Due to space needs, I had a need to change from one drive being partitioned to be 2 Superduper drives to having individual drives to replace the 2 patrons.  Now, this drive no longer ejects, possibly because I had to erase and reformat it.  I then added another drive and it too does not eject.

Of my 3 drives, the 1 (now 2) drives that ejected and were reformatted are Firewire 800 connected by Thunderbolt.  The Time Machine drive is USB 3.

Mo_SR wrote:

 

Depressingly I found this on another thread of a similar topic. Which basically says it's going to be luck, circumstance and device specific whether you get this situation or not. Technically you should be having the problem all the time. This is from an engineer at Sonnetech who actually sounds like he knows what he's talking about (and for USB/FireWIre I'm assuming we include include Thunderbolt 2).

 

The error messages are unavoidable:

 

As part of the sleep mode, and by design, the Mac computer cuts all power to the PCIe cards.  This causes a reset of the USB 3.0 and Firewire ports on installed PCIe cards when the power returns.

The drives will automatically remount, and the O/S backs-up data files that are open before the computer enters sleep, but the error message will still appear because OS X detects that the interface has been re-set.

Unfortunately the only way around this is to have the screen power down, but do not allow the Mac to enter power-off sleep mode.

In my case drives were not remounting, nor were available as unmounted in Disk Utility. In order to let them re-appear I had to physically disconnect them from their power supply and then re-plug. As I mentioned before in my case the issue happening on drives which were NOT bus powered, while the drive bus-powered didn't suffer from the issue.

After a relatively long time without the problem, since a clean install of El Captain, the problem returned.

Often I have to use Disk Warrior to recover the disk, since the ejection corrupts the drive and Disk Utility can't recover it

After a relatively long time without the problem, since a clean install of El Captain, the problem returned.

Often I have to use Disk Warrior to recover the disk, since the ejection corrupts the drive and Disk Utility can't recover it

My OSX version is 10.11.2. I tried disabling spotlight and even disabled sleep when I idle. My two USB 3 external HD that has time machine is connected to a USB 3 hub that has it's own power supply. The random ejection happens at the same time to both external HD with time machine. However a third external HD that does NOT have time machine never disconnects and no other device connecting to the hub has issues.This happens at random times when you return from sleep mode or even during normal use. This wasted my money to try different hubs until I realized this is Apple's faulty design. Please fix this..............

Thank you, uninstalling the Western Digital Utilities solved the random powering off of my external USB 2TB My Passport Ultra WD external hard drive.

P.S. This worked on a late 2008 13" Macbook with El Capitan installed.