Mounting external T-Bolt drives as part of the boot

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Level 1

18 points

Mounting external T-Bolt drives as part of the boot

After upgrading the M4 Mac Mini from Sequoia to Tahoe, the auto mounting of the two external Promise Tech Pegasus stoped working.

The Mini runs "headless" normally - no display and no keyboard.

The four drive Pegasus unit is used as a destination for Time Machine backup from my other Macs.

The 6 drive, 20tb array, is used as network attached storage which enables the sharing of files among all users. The much space is needed as quite a bit of photo and video files are stored and shared there.

The following command from terminal enabled things to work under Sequoia but only partially fixes it under Tahoe:

sudo defaults write /Library/Preferences/SystemConfiguration/autodiskmount AutomountDisksWithoutUserLogin -bool true

I would like for this mounting of external drives to work without any manual intervention at boot time.

Any ideas?

Mac mini (M4)

Posted on Oct 16, 2025 3:04 PM

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Answer 1

Top-ranking reply

BigUglyMike Author

Level 1

18 points

Oct 17, 2025 6:32 AM in response to neuroanatomist

Saw the "FileVault" setting while checking Privacy & Security.

After disabling FileVault and re-booting, the two Promise Tech Pegasus RAID arrays mounted at boot up.

To further test things, the entry in the SystemConfiguration directory for "autodiskmount" was deleted and the system re-booted.

Without the auto disk plist, the external drives DID NOT mount.

It appears that both FileVault needs to be disabled AND

the "autodiskmount" plist has to be in place.

sudo defaults write /Library/Preferences/SystemConfiguration/autodiskmount AutomountDisksWithoutUserLogin -bool true

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Answer 2

Oct 16, 2025 3:20 PM in response to BigUglyMike

Tahoe enabled FileVault by default, requiring login to complete booting up and preventing external drives from mounting before that happens. You can disable FileVault in System Settings > Privacy & Security > FileVault.

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Answer 3

AlWeir

Level 5

4,989 points

Oct 16, 2025 3:14 PM in response to BigUglyMike

Try looking in Privacy & Security. At the Very bottom under Security look for Accessories. One once click on it it will give your four choices

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Answer 4

Oct 17, 2025 2:27 PM in response to AlWeir

FileVault incorporates the user’s login password into the decryption key, so that only the user can decrypt the drive. That’s an extra jot of security over the Secure Enclave hardware encryption. But it requires that the user enter their password, i.e., log in, to fully boot up the Mac. In other words, it’s functioning exactly as designed. The difference with Tahoe is that FileVault is enabled by default.

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Answer 5

Oct 16, 2025 3:23 PM in response to AlWeir

AlWeir wrote:

Try looking in Privacy & Security. At the Very bottom under Security look for Accessories.

The OP would look all day without finding, since the OP has a Mac Mini, not a laptop. The setting to which you are referring is only present on Mac laptops.

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Answer 6

Barney-15E

Level 10

122,138 points

Oct 17, 2025 2:15 PM in response to AlWeir

AlWeir wrote:

You would have thought Apples technicians would have corrected this while Tahoe was in beta.

It was tested. That is how FileVault works. As an aside, you can now ssh into a FileVaulted Mac, which is an improvement over previous versions.

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Answer 7

BigUglyMike Author

Level 1

18 points

Oct 17, 2025 2:57 PM in response to neuroanatomist

It probably is working to the new design.

Even after seeing the term FileVault, the full meaning of it was not clear to this end user.

The two different Apple support folks with whom I talked did not know.

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Answer 8

Oct 17, 2025 3:20 PM in response to BigUglyMike

BigUglyMike wrote:

The two different Apple support folks with whom I talked did not know.

Apple tech support staff are well trained and have access to the full database of kbase articles, but the breadth and depth of the collective knowledge base of the members here is truly impressive.

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