How to boot from USB 3.0 disk through Thunderbolt dock?

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Level 1

8 points

How to boot from USB 3.0 disk through Thunderbolt dock?

Hello,

Hope someone can help with the following problem:

I recently bought the CalDigit Thunderbolt Station that I have hooked up to my mid-2011 iMac 21,5". I have also bought an Icybox external USB 3.0 enclosure with a Samsung SSD 840 drive installed.

My hope/goal was to use the SSD drive as a boot disk for my iMac, using USB 3.0 from the Thunderbolt Station. However, when the USB disk is connected to the Thunderbolt station it is not recognized at boot, and it does not show up in the startup manager. It does mount up normally in Finder as an external USB 3.0 drive. When connected directly to the iMac, using its USB 2.0 ports, it works fine as a startup disk.

Any clues to how to get the drive to work as a status disk using the USB 3.0 interface? Is this related to the firmware of the iMac, or could it be something do do with the external drive and incompatible USB controller?

Any help is greatly appreciated, thanks!

iMac, OS X Mavericks (10.9)

Posted on Nov 23, 2013 1:11 AM

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Answer 1

LowLuster

Level 6

12,105 points

Nov 23, 2013 2:00 AM in response to erlendbraten

Well if it doesn't show up at startup attached to that docks USB 3 port then you can't boot from it.

You could try selecting it in Startup Disk in System Preferences but I doubt the system will boot from it because it isn't showing from the Option key boot selection screen so at startup the Mac has no way to access it.

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Answer 2

erlendbraten Author

Level 1

8 points

Nov 23, 2013 2:14 AM in response to LowLuster

So it can't be fixed by a different enclousure? I've seen people recommending enclosures with the asMedia 1053e chipset, as it supports UASP. As far as I have been able to investigate, the Icybox does not have that chipset.

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Answer 3

LowLuster

Level 6

12,105 points

Nov 23, 2013 2:19 AM in response to erlendbraten

It seems not even the newest Mac computers that have built in USB 3 ports can boot the system from a USB 3 drive connected to them. Something to do with the USB 3 ports and connected USB 3 drives aren't seens and accessible at power on. Only after the OS starts can they be accessed. But those same ports do work with USB 2.0 drives.

You could try a real TB enclosure but that might have to be connected directly to the TB post on your Mac, not sure as I've never tried it.

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Answer 4

erlendbraten Author

Level 1

8 points

Nov 24, 2013 2:20 AM in response to LowLuster

Thunderbolt enclousure would probably work, but that was not the point here.

Seems from this discussion: https://discussions.apple.com/thread/5128258 that some are able to boot from external USB 3.0 drives. In that string it is also suggested that the type of enclosure (and then the different types of USB chipsets) determines if you'll get it to work or not.

Or is this something Apple can fix in future OS or firmware updates?

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Answer 5

LowLuster

Level 6

12,105 points

Nov 24, 2013 5:37 AM in response to erlendbraten

I doubt they will fix it. Apple has invested heavily in Thunderbolt and only added USB 3 after they realized they couldn't continue supplying computers without it. The cost difference between a USB 3 external and that same size drive in a TB enclosure is several hundreds of dollars.

So only time will tell if they fix it on older Mac computers or it is fixed with newer systems.

erlendbraten wrote:

Or is this something Apple can fix in future OS or firmware updates?

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Answer 6

kibosh

Level 1

15 points

Aug 15, 2014 2:41 PM in response to erlendbraten

Just follow my walkthrough here (http://www.michaeljjensen.com/tech/) to make a natively bootable Windows USB 3.0 drive. It is pretty simple and then you don't have to worry about all the people above who told you your dream wouldn't happen. I got tired of that so I just figured it out myself.

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Answer 7

Old Toad

Level 10

207,367 points

Aug 15, 2014 3:17 PM in response to kibosh

How does that help erlendbraten boot his Icybox external USB 3.0 enclosure with a Samsung SSD 840 drive installed via the USB 3 port?

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Answer 8

Aug 16, 2014 2:22 AM in response to LowLuster

LowLuster wrote:

It seems not even the newest Mac computers that have built in USB 3 ports can boot the system from a USB 3 drive connected to them.

Not true. I do this nearly every other day with a Seagate external USB3

directly connected to my recently purchased 27" iMac. Also do this with

a Startech USB3 portable enclosure.

Going through a dock, however, is likely the source of the issue, since

it may require initialization by the OS for use thus the external drive

is not seen at the right time in the boot sequence.

It is a fact however, that some USB enclosures chipsets do not support booting.

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