TerraMaster Official Forum

I just added a D4-300 (populated currently with 2 x 3TB HDD) to my 2018 Mac mini running BigSur. I have the two drives configured as an OSX mirrored RAID, and everything works fine... until I reboot the Mac. When the system comes up after a boot, the D4-300 doesn't show up. Even in disk utility it isn't visible as an unmounted set of drives. Power cycling the D4-300 doesn't help. The only "solution" I've found is to unplug the USB cable from the Mac, and then plug it back in. The devices appear immediately, and the file system mounts the drives within a few seconds after that.

I have 2 other external drives which do not suffer this problem, mounting immediately upon the system booting. This seems to be unique to the Terra-Master enclosure. Needless to say, having to re-plug the device on every boot (which I do frequently for other reasons) is seriously inconvenient. I'm tried resetting the OSX usb daemon, but this doesn't appear to have any effect.

Please advise whether you are using the original USB cable, and connect to the Mac directly without any adapter.
One of our users reported the same issue before, and was fixed by resetting the Mac.

I am using the USB cable that came with the enclosure, and have it plugged directly into one of the two USB 3.1 ports on the back of the Mac mini. I have done an option-command-P-R reboot to reset the PRAM, however this did not correct the issue.

Any suggestions? This issue is quite annoying since I switch to/from Bootcamp (on a different drive) daily, and thus have to unplug/replug every time I boot back into OSX.

Hello?

Sorry to reply you late.
We have no idea what happened to your device, as D4-300 is a very common JBOD enclosure. Not sure if it is related to system configuration. Please try it on another computer, or try to change settings in your computer configuration.

I tried to find out possibly solutions, please check it if these help

https://iboysoft.com/mac-data-recovery/ ... g-mac.html
https://www.techjeny.org/external-drive ... s-big-sur/

Unfortunately these articles (and all the others I've found) presume that the device doesn't mount at all. In this case the D4-300 just doesn't mount when I reboot into OSX. If I unplug/replug the device, it is recognized immediately and everything is fine. I've even tried resetting the USB bus via a dev utility, and that doesn't work. Powering cycling the D4-300 also doesn't work. The USB connection, at least thus far, must be physically severed and then re-established. I have 3 USB storage devices, and this is the only one suffering from the issue.

D4-300 is an independent single-disk hard disk box, which does not support RAID itself.
It is recommended that you try the normal use method according to the installation guide to see if the same problem occurs.

Alright, I removed the OSX RAID functionality and am now using it as 2 independent drives. Problem still occurs.

And now one of my 2 drives isn't appearing.