Again, not singling you out (so my apologies if it felt like that)- just talking in general, trying to be helpful to others who might read this thread looking for solutions. Many people hit many of the threads about "this issue" and redirect it to anything & everything other than Apple. For example, your first post in response to me seemed to be trying to single out docks as a culprit. Others pitch cable, firmware, enclosure, brand, drive, age, settings and user error in spite of certainly seeing over and over in all of these threads that this is not some isolated incident where it could be just one thing like any of that.
And "this issue" is about MACs unexpectedly ejecting external drives. You're the one who brought Windows and linux into the conversation... perhaps out of confusion that my own posts were very specifically about Macs... as Macs are the only thing running macOS.
"this" is defined as spontaneous unexpected ejections, often in enclosures that were perfectly stable in < BigSur versions of macOS. All of the variables that often get blame tend to be the same variables that used to maintain a stable connection to a Mac. Then one upgrades to Big Sur or newer and that's not the case anymore. No variables changed except the macOS upgrade. In SOME of those cases, the Mac user needed the drive more than they needed the macOS upgrade, so they went to the trouble to downgrade again... after which EVERY SINGLE report I've seen led to a stable drive again.
None of that says that there won't be dock disconnect stories for any platform if one does that kind of search. Try a search for "iPhone spontaneous combustion" and you'll find those stories. Try "iPhone is possessed" and you'll find stories about that too. The first one is in an Apple Support Community.
My replies to your posts were not denying that docks can unexpectedly eject drives... just that THAT is not the narrow cause of this problem specifically with Macs running Big Sur and newer with select- but not all- attached drives. Many of these cases are direct connect- no docks involved and/or when docks were playing middleman, Mac people trying to solve this themselves have experimented with direct connect to rule out a defective dock. Generally, there's little success there, because that doesn't seem to be much of a contributor to this problem for Mac people.
I pounded through some docks & hubs myself trying to solve this problem. My best guess is that this problem is grounded in power management and/or port management... and the working hypothesis that I can't directly test is that since Silicon Macs lean on iDevice code and iDevices by nature don't tend to have HDD enclosures attached to them for any length of time, iOS code supporting attached devices tries to work power down to maximize battery life... dropping below some threshold that keeps select enclosures attached. Even though this code is in select Macs with no batteries at all- like my own Studio Ultra- I suspect the algorithms are still in play. So, an idea was that perhaps a powered hub or dock would maintain the power sipping relationship to the Mac and then manage the power connection to the drive itself, NOT fall below the threshold and thus never unexpectedly eject the drive. Result: No noticeable change... unexpected ejections as before.
Hypothesis #2: do Silicon ports "crash"/"reboot"? I can very tangibly see that an ethernet port seems to crash/reboot from time to time. If other ports do the same, select enclosures may not be able to recover from the temporary virtual disconnect and thus "unexpectedly eject" while others can handle it. To me this would be bugs in port management software and yield the same seemingly random experiences. No way I know to test this myself but Apple could.
However, all that offered, if you want to do web searches, try "macOS unexpected ejection" and "Mac unexpected ejection." You'll find pages and pages of matches all over the web about this particular problem with Macs and drives, including a number of them on latest & greatest Mac releases on Apple's own support forums. You'll also find many very hopeful headlines & videos that offer "the solution to Mac unexpected ejections" until you dig into the solution and typically find the person thought they had it, it seemed to work and then the unexpected ejections resume again.
I've been there. I've worked through ALL of the apparent solutions that users can try. I've dug out every USB hard drive I've owned in the last 20+ years to try to test a wide variety of hardware, firmware, drives, cables, brands, etc. I've attacked the most blamed issue- SLEEP- by not letting my problematic drive or Mac sleep at all only to watch it unexpectedly eject while actively transferring files to/from it (so obviously nothing is asleep). I've tried the deep stuff like tweaking a terminal setting that one can find if they really dig into this topic. Etc.
It's this great effort and chasing every rabbit down every hole that led me to conclude that the problem is macOS. I'll grant that I could be wrong about that as the one thing I can't do is install pre BigSur on my Silicon Mac. So I've basically landed at macOS as best guess.
Leave this thread and come back in a week or two and there will be 5 or 10 new posts blaming cable, user, firmware, etc... which- if true- great... but then we would have already resolved this problem years ago and all of these many threads would name the bad cable or specific enclosure or specific firmware. However, all that really works is enclosure roulette: try different ones until you find one that can stay connected. Retire the one that won't or use it with old Macs or any PC where it will be perfectly stable.
I'm towards 99% convinced that there will eventually be some modest or even minor macOS update where this problem will be resolved for just about all. Why? Because that will be the one where programmers finally worked over the specific macOS code that is at the root of this problem. Nobody will have to change cables, change firmware, change drive, etc... it will just resume working again as- for many of us- the drives worked before we went BigSur or newer. As new versions come out, people test what was "old reliable" hoping that this one will be the one... only to be disappointed that once again, another episode of NOT "just works" persists. Yet we hope and hope and hope that our newest Macs will be able to do a "Universal" thing that our older Macs were able to do... and can still do.
