Mac Pro, target display mode to iMac, thunderbolt drive ejects?

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Mac Pro, target display mode to iMac, thunderbolt drive ejects?

So my set up is a Mac pro 2013 with a Lacie 4tb thunderbolt drive connected, then from another thunderbolt port the iMac is connected. I have no issues with target display mode as all appears to work fine. The issue I encounter is the drive keeps ejecting almost 2 mins in to using it.

Here are a few things I tried

Swapped thunderbolt cable, same problem

Swapped Thunderbolt for USB 3 cable No issues this works (would prefer to use Thunderbolt)

Put hard Drives to sleep when possible is off.

Now I am thinking the issue might be similar to this, back to when I tried using Firewire 800 to share the internet to another computer I had a firewire drive connected to it too, this meant whoever switches on first gets the hard drive! Could Thunderbolt be doing the same thing and as a result get ejected, is there away the drive could be "pair" to the computer to prevent that?

Mac Pro, OS X El Capitan (10.11.1)

Posted on Dec 1, 2015 1:29 AM

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Answer 1

Camelot

Level 9

54,333 points

Dec 1, 2015 1:34 AM in response to MattJayC

I think you've accurately self-diagnosed the problem - both host systems see the drive and assume they 'own' it, which isn't viable.

There's no way (that I know of) to 'pair' devices or mask them to only link to one host. The best solution is to put the drive on a different, non-shared bus such as the USB.

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Answer 2

Dec 1, 2015 1:35 AM in response to MattJayC

I don't have a new Mac Pro or new iMac for that matter so cannot speak from personal experience but see the following.

There are three different Thunderbolt 'busses' on the new Mac Pro, you could try connecting the hard drive and the iMac via different busses and see if that helps. See Use multiple displays with your Mac Pro (Late 2013) - Apple Support

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Answer 3

Camelot

Level 9

54,333 points

Dec 1, 2015 4:37 PM in response to John Lockwood

John, according to the OP he's already doing that.

Mac pro 2013 with a Lacie 4tb thunderbolt drive connected, then from another thunderbolt port the iMac is connected

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Answer 4

Dec 1, 2015 7:55 PM in response to Camelot

Camelot wrote:

John, according to the OP he's already doing that.

Mac pro 2013 with a Lacie 4tb thunderbolt drive connected, then from another thunderbolt port the iMac is connected

There are 6 Thunderbolt ports but only 3 busses on the new Mac Pro. It is quite possible he has picked another port on the same bus. It is therefore worth checking against the diagram via the link I provided.

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Answer 5

MattJayC Author

Level 1

14 points

Dec 2, 2015 3:03 AM in response to John Lockwood

0 - 0

X - X

The above was the set up, however I have now changed it to this

0 - 0

X - 0

0 - X

and so far this appears to help, should have tried this sooner, but after having a few issue with El Capitan I just assumed it was another bug,

Its been about 2 hours in and no issues.

I'll keep you posted, thanks for the help.

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Answer 6

MattJayC Author

Level 1

14 points

Dec 2, 2015 6:17 AM in response to MattJayC

Ok I Still have the problem,

I have now tried this combination and it is the same.

X - 0

0 - 0

0 - X

I checked the iMac to see if they had been mounted, and they hadn't.

I thought i'd check the 'about mac' and get a system report. when I clicked on thunderbolt it made the system crash!

On reboot once the drive was connected it did show that its on a different bus.

Hope there is a solution for this.

Matt

EDIT> just ejected while in the middle of writing a file! Annoyingly back to USB 3! Could have a bought a much cheaper drive if just USB 3.0

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Answer 7

MattJayC Author

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14 points

Dec 17, 2015 6:45 AM in response to MattJayC

So I have tried various setups including trying an identical laCie model on the macPro and no issues, so it actually looks like my drive is at fault but only in this setup. Lacie/Seagate are arranging for the drive to be replaced, so will let you know how it goes once I receive it.

Matt

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Answer 8

Dec 17, 2015 8:12 AM in response to MattJayC

Do you really need Target Display Mode?

You could connect via Screen Sharing, and still be able to compute on both computers. The only downside is the connection is not really fast enough for Video editing, but it works for almost everything else with an Ethernet connection. I use mine with Gigabit Ethernet switch and it saves me running to the basement to fiddle with my Mac Pro Server.

On the Mac Pro:

System Preferences > Sharing > Screen Sharing

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Answer 9

MattJayC Author

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14 points

Dec 17, 2015 8:52 AM in response to Grant Bennet-Alder

I definitely need to use Target display mode else I have no screen for the MacPro, it would be too slow too, using it for photoeditting, I've tried something similar before and turn the macPro into a headless system means you also get a smaller resolution than what a 27" screen can do.

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Answer 10

Dec 17, 2015 9:04 AM in response to MattJayC

Most Photo and Video editors are using one (or two, or three) smaller displays directly attached to their Mac Pro to do that work. You can put all the controls and menus on a screen by itself and use another for the final output. Two smaller screens can be used to good advantage that way for far less money.

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Answer 11

MattJayC Author

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14 points

Dec 17, 2015 11:51 AM in response to Grant Bennet-Alder

screens aren't the problem. It's that the thunderbolt drive that keeps ejecting

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Answer 12

Dec 17, 2015 11:58 AM in response to MattJayC

If screens are not the problem, you should get two different ones and get off this "emergency" method of connection and use some real screens.

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