Do I need to unmount the internal HDD to prevent conflict?

Do I need to unmount the internal HDD to prevent conflict with the external SSD I use as start up disc? The iMac shuts down occasionally and this is the only thing I can think of which may cause this.

iMac 21.5″, macOS 14.5

Posted on Jul 24, 2024 2:53 PM

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3 replies

MartinR

Level 7

26,490 points

Jul 24, 2024 5:52 PM in response to K Walder

There is no conflict. The shutdowns are being caused by something else, not the fact that the internal HDD is mounted. When booted from an external drive, the internal drive would just be seen as an available data drive.

What external SSD are you using, what enclosure is it in, how is it connected to your iMac and is a USB hub in the chain?

It would also help to know the exact model iMac you have.

Jul 24, 2024 4:08 PM in response to K Walder

I don't believe that the internal drive should cause a conflict once the system has properly booted from an external source. The things that you might want to check is the connection to your external source (the communication cable and power source) and any logs in the console app that might display why these random errors are happening. You can use the disk utility to run a file system check by selecting the drive and using the first aid button to scan the drives internal and external and make any necessary basic repairs to the file system. The logs in the console should guide you in the right direction to find out what is happening. I hope that this helps you to resolve the problem.

rkaufmann87

Level 10

149,402 points

Jul 24, 2024 3:47 PM in response to K Walder

There is no context to questions so please look over Writing an effective Apple Support Communities Question and then re-write.

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Do I need to unmount the internal HDD to prevent conflict?