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mj62mj62 Author

Level 1

8 points

Booting from external SSD fails when 2 SSDs connected

Hello,

My iMac boots from an external SSD. However when an additional external SSD is plugged in, the boot fails (around the 90% point of the apple progress bar).

I suspect that the iMac cannot power 2 SSD's because the lights on the SSDs go out (one of them has an always-on light to show it is connected and the other blinks when accessed. Both show no activity after the 90% point in the boot cycle)

My workaround is to boot from the main SSD, then plugin the second SSD. But this an awkward setup for a family computer.

Is there any way to fix this issue?

Thanks

iMac Line (2012 and Later)

Posted on Nov 26, 2021 2:57 AM

Top-ranking reply

Old Toad

Level 10

210,189 points

Posted on Nov 26, 2021 3:29 PM

You can get a self powered dock and plug the two external SSDs into it. I have 5 SSDs connected to my iMac, 4 in self powered caddy and one connected directly to the iMac. I have no problem on booting, even when booting into one of the external SSDs.

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Booting from external SSD fails when 2 SSDs connected

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