Does Monterey Have a Bug with Mounting External Drives & Images?

[HobeSoundDarryl]

Yes, 12.6 seems to have done it (so far) for my HDD RAID enclosure. It was perfectly stable on the Intel iMac running macOS before Big Sur for a couple of years. Then I got Mac Studio Ultra in April and expected "just works." However, it could not maintain a connection for longer than about 3 hours, whether the Mac went to sleep or was in active use the entire time. I even had it "unexpectedly eject" while actively transferring files to and from it.

Of course, most posts about it in any Apple forum led to endless redirection to anything and everything else it could be other than Silicon or Monterey as I suspected. I did test through EVERYTHING a user could do before reaching a conclusion that either Silicon or Monterey was at fault. If all variables like cable and enclosure work fine on several Intel Macs running an older version of macOS but "unexpectedly ejects" from a Silicon Mac running Monterey, so much of the redirection didn't seem to logically apply.

Apparently (so far anyway) that hypothesis was correct. I've been re-testing in every point upgrade of Monterey and with 12.6 it suddenly "just works" again (so far). It's great to have access to faster, much bigger storage again than the one-drive option I had subbed in while hoping this day would come.

So anyone suffering the same kind of funky USB (worked fine on Intel Macs but doesn't work with a Silicon Mac running Monterey or Big Sur) might want to freshly test anew. It appears (to me anyway) that Apple has done something in "Universal" serial bus management with this point upgrade. I suspect a LOT of "no longer works" USB stuff will now work again.

I also wonder if Apple debugging may have done something about speeds of Silicon USB not being as implied, ethernet connection seeming to regularly reboot several times each day (I've experienced this every day since Studio arrived myself) and the weird issue of insufficient power when more than 1 or 2 things are connected to Mac Studio in spite of it seeming to have a plentiful source of power in the power supply. Hopefully, Apple killed several birds with one stone while in there (hopefully) making the U in USB work again (so far).


Update: perhaps my enthusiasm for a solution at last jinxed it. Soon after posting...

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How aggravating!!! Here's hoping Apple fixes this in Ventura. ☹️

 

[Brian33]

Update: perhaps my enthusiasm for a solution at last jinxed it. Soon after posting...

Sigh. Feeling sad for you. :-(

I suppose I'm lucky that my ejections occur only once a month or so; still, I'm concerned about filesystem corruption.

 

[HobeSoundDarryl]

Yes, I’ve researched this topic to death. Some enclosures work fine, some have this problem only periodically (like yours), some are more like mine and some are worse.

But the general theme is that about all of those with issues work fine on Intel Macs running macOS BEFORE Big Sur… and in some reversions back to such OS versions, they work again. In my case, unhook mine from Silicon + Monterey to Intel + before Big Sur and it works fine again. Try Monterey again and it’s good for some amount of time- usually 3 hours or less- but will unexpectedly eject.

Nevertheless, this update makes me believe Apple did something this time, so hopefully they will finish whatever debugging/optimizing they may have started. Else, it was just a freak run, longer than any time before on Monterey…and I’m back to the more dependable single drive substitution (slower and smaller storage but doesn’t unexpectedly eject)… hoping Ventura brings “universal” back for all of us affected.

 

[Alvin777]

Yes, I’ve researched this topic to death. Some enclosures work fine, some have this problem only periodically (like yours), some are more like mine and some are worse.

But the general theme is that about all of those with issues work fine on Intel Macs running macOS BEFORE Big Sur… and in some reversions back to such OS versions, they work again. In my case, unhook mine from Silicon + Monterey to Intel + before Big Sur and it works fine again. Try Monterey again and it’s good for some amount of time- usually 3 hours or less- but will unexpectedly eject.

Nevertheless, this update makes me believe Apple did something this time, so hopefully they will finish whatever debugging/optimizing they may have started. Else, it was just a freak run, longer than any time before on Monterey…and I’m back to the more dependable single drive substitution (slower and smaller storage but doesn’t unexpectedly eject)… hoping Ventura brings “universal” back for all of us affected.

So true, I've noticed this too with Big Sur but Monterey has made it full blown. A user here says, Ventura did not fix this issue (at least on the Beta), we have to message Apple (I've sent this to Feedback app, I'll send it again but there's strength in numbers) to fix this very important problem, else backing up is impossible (as mentioned I've not backed up for a year now). Let's deeply hope & pray Apple is not deliberately crippling relatively old external storages- a forced obsolescence.

 

[HobeSoundDarryl]

I've sent this feedback to Apple too.

Apple support site had extensive threads on this issue, one with many pages of people sharing this problem and trying all kinds of user remedies (which I tried too). However, Apple seemed to have deleted those threads, which I do not take as encouraging.

I have tested so many times as Monterey has moved along and never had this enclosure go this long without "unexpectedly ejected" so I do think they are doing something about this... but apparently have more to go.

I recall seeing something in some story where Apple insiders were admitting that there was a LOT of optimizations of macOS for Silicon to be done. Unfortunately, I didn't recall where I saw it. Logically, that makes sense even 2+ years in now. So hopefully, they are working hard at optimizing and bug fixes for Silicon so that this kind of thing gets resolved soon. Existing in Big Sur (for some) and Monterey doesn't load me with confidence but hopefully... EVENTUALLY... they make this part of Silicon "universal" again.

 

[Alvin777]

I've sent this feedback to Apple too.

Apple support site had extensive threads on this issue, one with many pages of people sharing this problem and trying all kinds of user remedies (which I tried too). However, Apple seemed to have deleted those threads, which I do not take as encouraging.

I have tested so many times as Monterey has moved along and never had this enclosure go this long without "unexpectedly ejected" so I do think they are doing something about this... but apparently have more to go.

I recall seeing something in some story where Apple insiders were admitting that there was a LOT of optimizations of macOS for Silicon to be done. Unfortunately, I didn't recall where I saw it. Logically, that makes sense even 2+ years in now. So hopefully, they are working hard at optimizing and bug fixes for Silicon so that this kind of thing gets resolved soon. Existing in Big Sur (for some) and Monterey doesn't load me with confidence but hopefully... EVENTUALLY... they make this part of Silicon "universal" again.

Hi. I guess those without  Silicon Macs w/ USB-C and future USB/Thunderbolt external storage will be toast if Apple, like how the USB in the first iMac replaced the parallel and serial ports is making non-USB-C (and later) external storage obsolete or not work consistently but hopefully not, coz' that's a lot of electronic waste if it can't be used. I sometimes manage to make the external storage mount by chance (sometimes after a reboot from Boot Camp or from a shutdown). For good measure, it's time to start saving up for  Silicon Macs, hopefully next year there's the Mac Pro w/ 33" or OLED  monitor and 2nm  SOC w/ the SSD in the SOC as well (1TB is the sweet spot) so it's way faster then 7GB/s bandwidth and as fast as the fastest RAM but is non-volatile.

By the way does everyone who have this issue have Boot Camp installed (Windows 10 or 11 or any Windows)? If yes, there might be a connection coz' sometimes after booting from Boot Camp (which again all external drives mount without problems), the Bluetooth wouldn't work on macOS, I have to remove and pair the Magic Mouse again, as if macOS is getting confused and maybe it's locking the external drives (the external drives are "hijacked") to Windows Boot Camp (like it does when you use a Virtual Machine with macOS as the client OS). Thanks.

 

[HobeSoundDarryl]

At least in my case, I have not experienced those kinds of bootcamp issues.

Also in my case, the external is perfectly reliable (remains connected) to Intel Macs I have with and without bootcamp and flipping back & forth between using bootcamp.

The unexpected ejection is on Mac Studio Ultra (obviously) with no bootcamp. What I've seen in all of the research is a general theme of enclosures working just fine on Intel Macs until they upgraded to Big Sur or Monterey. Then some- but not all- start doing this "unexpected ejection" thing. In a few posts, I've seen people choose to blame Big Sur or Monterey and then downgrade or boot back into macOS BEFORE Big Sur and the same enclosure linked by the same cable returns to remaining consistently connected.

Since my own Intel Macs are running macOS before Big Sur, this enclosure has no issue if I hook it to them. However, my "latest & greatest" Studio Ultra cannot maintain the connection. To me that puts the issue with either Silicon or Monterey. I wish I could try a pre-Big Sur macOS on this device to pin it down to where I think the bug(s) really lies- Monterey- but no way to do that.

The idea that Apple is purposely choosing to obsolete some USB hardware is plausible, but it's so random. Basically some stuff works and some doesn't with no obvious clue of what is likely to work or not work. For example, the enclosure that doesn't remain connected to Studio Ultra and one that does BOTH come from OWC. There are reports of this in many posts where one thing from a brand works and something else from the same brand doesn't. In my case of trying to figure this out, I dug out some ancient, retired drives for testing- stuff from as far back as the early 2000s. Generally much of that connects and remains connected while the much newer enclosure won't. I would think that if Apple is doing this by some kind of plan, that older stuff would definitely be on the deprecation list too.

Through the narrow band of my own testing with various enclosures old and new and much research about this topic, the problem:

• seems to be much more weighted to HDD enclosures than SSD,
• isn't resolved for all by inserting a powered or unpowered middleman (hub) device,
• occurs regardless of which port is used on Silicon and
• seems most likely to show itself in RAID enclosure setups.

Personally, I suspect that the ports crash & reboot regularly and that many devices can handle the temporary disconnection while others are more sensitive. I notice that the ethernet port seems to "hang" for up to a minute or two several times each day. If I quickly switch to wifi, there is definitely internet. Switch back and ethernet may still be hung. Give it up to a minute or two and it works again. I suspect that it too is "rebooting" and wonder if there is a relationship between ALL ports along this line of thinking- some kind of all port "manager" occasionally crashing/rebooting all ports.

Many people think this probably is related to sleep, but I've had it disconnect while in active use (transferring files to or from it). I do think sleep functionality probably has some relationship here too but I don't think it is entirely about sleep. Instead, I suspect power-sipping optimizations for iDevices live on in Silicon Mac and that power levels are worked down below levels certain enclosures can tolerate... great for iDevices on battery without having such devices connected... not great for battery-less Macs plugged in that should not need so much power-pinching on the ports. However, that's just a hypothesis. I have no way of proving it.

Until this 12.6 upgrade, the best I was getting almost every time with this enclosure was up to about 3 hours. This version has given it about 14-18 hours TWICE now (concluded by 2 "unexpected ejections"). So I suspect there is some work (finally) being done with the port management software of macOS but they don't quite have all bugs squashed. Now that it's been 2 times, I no longer think the first run was a freak event... that Apple has actually done something new about this issue. I hope they keep at it to eradicate and/or optimize whatever else is still driving ejections. It would be nice for the U in USB to apply again.

 

[Alvin777]

At least in my case, I have not experienced those kinds of bootcamp issues.

Also in my case, the external is perfectly reliable (remains connected) to Intel Macs I have with and without bootcamp and flipping back & forth between using bootcamp.

The unexpected ejection is on Mac Studio Ultra (obviously) with no bootcamp. What I've seen in all of the research is a general theme of enclosures generally working just fine on Intel Macs until they upgraded to Big Sur or Monterey. Then some- but not all- start doing this "unexpected ejection" thing. In a few posts, I've seen people choose to blame Big Sur or Monterey and then downgrade or boot back into macOS BEFORE Big Sur and the same enclosure linked by the same cable returns to remaining consistently connected.

Since my on Intel Macs are running macOS before Big Sur, this enclosure has no issue if I hook it to them. However, my "latest & greatest" Studio Ultra cannot maintain the connection. To me that puts the issue with either Silicon or Monterey. I wish I could try a pre-Big Sur macOS on this device to pin it down to where I think the bug(s) really lie- Monterey- but no way to do that.

The idea that Apple is purposely choosing to obsolete some USB hardware is plausible, but it's so random. Basically some stuff works and some doesn't with no obvious clue of what is likely to work or not work. For example, both the enclosure that doesn't remain connected to Studio Ultra and one that does BOTH come from OWC. There are reports of this in many posts where one thing from a brand works and something else from the same brand doesn't. In my case of trying to figure this out, I dug out some ancient, retired drives for testing- stuff from as far back as the early 2000s. Generally much of that connects and remains connected while the much newer enclosure won't. I would think that if Apple is doing this by some kind of plan, that older stuff would definitely be on the deprecation list too.

Through the narrow band of my own testing with various enclosures old and new and much research about this topic, the problem seems to be much more weighted to HDD enclosure than SSD, isn't resolved for all by inserted a powered or unpowered middleman (hub) device, occurs regardless of which port is used on Silicon and seems most likely in RAID enclosure setups.

I suspect the the ports crash & reboot regularly and that many devices can handle the temporary disconnection while others are more sensitive. I notice that the ethernet port seems to "hang" for up to a minute or two several times each day. If I quickly switch to wifi, there is definitely internet. Switch back and ethernet may still be hung. Give it up to a minute or two and it works again. I suspect that it too is "rebooting" and wonder if there is a relationship between ALL ports along this line of thinking.

Many people think this probably is related to sleep, but I've had it disconnect while in active use (transferring files to or from it). I do think sleep functionality probably has some relationship here too but I don't think it is entirely about sleep. Instead, I suspect power-sipping optimizations for iDevices live on in Silicon Mac and that power levels are worked down below levels certain enclosures can tolerate... great for iDevices on battery without having such devices connected... not great for battery-less Macs plugged in who may not need so much power-pinching on the ports. However, that's just a hypothesis. I have no way of proving it.

Until this 12.6 upgrade, the best I was getting almost every time with this enclosure was up to about 3 hours. This version has given it about 14-18 hours TWICE now (concluded by 2 "unexpected ejections"). So I suspect there is some work (finally) being done with the port management software of macOS but they don't quite have all bugs squashed. Now that it's been 2 times, I no longer think the first run was a freak event... that Apple has actually done something new about this issue. I hope they keep at it to eradicate and/or optimize whatever else is still driving ejections. It would be nice for the U in USB to apply again.

Hi, I could conclude 95+% this is something they did in Big Sur and then it got worse in Monterey because all the external drives work flawlessly & mounts on Windows, also in High Sierra (could be installed in a small partition to test things out) & for sure before Big Sur. My .dmg and images don't mount too, it's been a year of no backup, no images mounting. I hope Apple fixes this this month.

I wonder what they changed in USB & Thunderbolt in Big Sur where it started that transferred to Monterey?

 

[HobeSoundDarryl]

Only Apple knows. We all can only guess.

One guess: Silicon is basically A-Series technology evolved for laptops and desktops. A-Series has generally not needed the ability to link to anything like external RAID enclosures, etc until fairly recently... and especially for days or weeks at a time. A-Series tech is also heavily focused on battery life, so optimizations generally revolve around maximizing battery.

I have seen posts that M-Series OS stuff is borrowing heavily from prior silicon code from earlier generation stuff. For example, in the lengthy thread in which Studio owners like me can't hook more than about 2 things that draw power from the jacks even though the power supply should be able to deliver that power, there is speculation that jacks management code for Studio simply came from MBpro code. If so, MBpro is also very concerned with battery life and thus may try to minimize power draw on ports. Some of these external enclosures may need a bit more than some optimized level selected by Apple (for MBpro)... and/or some kind of AI-driven power "trimming" works it down to a "too far" level and that yields the ejection.

My own guess: I'm highly suspicious that the ports "reboot" regularly, making this not a "only USB" issue. Again, first hand, I experience ethernet internet stalls for up to 2 minutes several times each day. Other devices using the same Internet connection are not stalled. If I wait for as much as the 2 minutes, the stall will cease and load. OR if I quickly switch to wifi, the stalled page will load. If I notice this early enough, I can switch to wifi to verify it is not my router/broadband connection, then switch back to ethernet to see the stall is still in play. It always comes back again, much like a rebooted computer will eventually be a usable device again.

So I think the ports in general reboot several times each day. When they do, "unexpected ejection" can occur on some devices that need ports to not be rebooting. If this guess is true, other enclosures apparently tolerate temporary disconnects better... such that this is not affecting ALL enclosures.

More simply, I think power-per-watt focus may be too much in place for Macs that don't need to be overly concerned with that (because they have no battery). I suspect code designed to maximize battery life is working against dependable connections over days/weeks of some third party enclosures.

However, that's one big guess that may or may not have anything to do with it. It still could be something wrong with Silicon itself, planned (but curiously selective) obsolescence, firmware conflicts (needing updates), etc.

I suspect there is PLENTY of room for macOS to fully adapt to Silicon... and that things like this are not yet "tuned" for Silicon in a complete way. Maybe Ventura will address this part of things? From a consumer/user perspective, it is not fun playing USB roulette, where some USB things may work and some won't, with no way to tell which will except try. That's missing the entire point of "UNIVERSAL" serial bus.

 

[Alvin777]

I just bought a SATA SSD (though I installed High Sierra in another volume, so it 100% mounts all the time, High Sierra is my back up macOS), it seems to mount if I first power the USB dock (with the SSD already plugged in the dock else it'll get damaged, it's not hot swappable) wait 40 seconds to be sure and then plug in the USB, wait a 1 minute to give it a change to mount on its own, if not I plug in a Flashdrive to help macOS Monterey mount it- will try a few more times for consistency.

 

[EssentialGadget]

There are huge problems with Monterey and external SSDs - especially 4TB.

I had to revert back to big sur which cleared up all problems. I have a 2019 iMac i9 booting from a 4tb Samsung EVO 860 in oyen enclosure.

Monterey 12.1 hangs formatting these external USB drives and installing to them. Also it cannot mount many external drives. A lot of issues with G drives. Some have had some success using a USB 2.0 cable - that is too slow and there is no guarantee that your data integrity is good. USB3C and USB3A don't make a difference.

Western Digital has announced there is a compatibility issue

This is a big problem - not sure why it has not been broadly recognized. Search web and you will find lots of people have this issue. Unstable mass storage is the death of a computer system. It is clearly the OS.

Monterey cannot erase external SSD

I am on Monterey 12.01 with my new 14" Macbook Pro M1 Max. I tried to use disk utility to erase 2 of my external SSD from exFAT into APFS. I tried the GUI Disk Utility and Terminal command, basically tried everything that I could search on Google but was not successful. Every time MacOS just...

forums.macrumors.com

Monterey struggling with External SSD - Apple Community

discussions.apple.com

Trying to decide if i need to revert my MBP2019. It runs on Apple internal 2TB SSD and appears to be working fine.
It couldn't format the EVO either or install to it.

Strongly suggest you do not upgrade.

UPDATE

I posted earlier about issues where Monterey would not read or format my Samsung 4TB EVO 860 SSD. Big Sur worked perfectly with it but multiple Monterey machines would not. I used it as a boot drive on a 2019 iMac.

I upgraded to a MacStudio with 4TB SSD and it would not read this drive either. Had to migrate from a 5TB HDD.

I finally had some time to experiment some more. I connected the drive to a Monterey 12.4 2019 Intel i9 MBP.
I formatted it to EXFAT GUID Partition. It took at least 30 minutes to an hour. Just let it crank.

It finally completed. Worked fine. I then formatted it APFS GUID Partition. Formatted quickly as expected. Works fine - 500+MB read/write on Blackmagic.

Currently using as a backup drive with MacStudio - no issues.

I will probably rotate all my SSDs and HDDs through this process to make sure they are Monterey compatible. Some of my HDDs seem a little too slow/quirky on Monterey.

Just remember the EXFAT format can take a long time.

NOTE: I used a USB 3.x cable for this.

 

[Alvin777]

UPDATE

I posted earlier about issues where Monterey would not read or format my Samsung 4TB EVO 860 SSD. Big Sur worked perfectly with it but multiple Monterey machines would not. I used it as a boot drive on a 2019 iMac.

I upgraded to a MacStudio with 4TB SSD and it would not read this drive either. Had to migrate from a 5TB HDD.

I finally had some time to experiment some more. I connected the drive to a Monterey 12.4 2019 Intel i9 MBP.
I formatted it to EXFAT GUID Partition. It took at least 30 minutes to an hour. Just let it crank.

It finally completed. Worked fine. I then formatted it APFS GUID Partition. Formatted quickly as expected. Works fine - 500+MB read/write on Blackmagic.

Currently using as a backup drive with MacStudio - no issues.

I will probably rotate all my SSDs and HDDs through this process to make sure they are Monterey compatible. Some of my HDDs seem a little too slow/quirky on Monterey.

Just remember the EXFAT format can take a long time.

NOTE: I used a USB 3.x cable for this.

Thanks. They say, at least the Ventura beta tester/s (I read somewhere), this wasn't fixed in Ventura. This external drive issue started with Big Sur if I can remember (wasn't that bad) but let's deeply pray, fast & deeply hope the final Ventura version will have these massive bug fixed (I can backup my system now but it took a year an an SSD for the external and some ritual/steps to get Monterey to mount external drives, finally (it still won't mount images like .dmg, it's a good thing there FastDMG app- I'll donate to that guy someday soon).

 

[Alvin777]

Update: it seems it's fixed now, I got to finally back up my system on the new Crucial SSD and the .dmgs now mount as well, after 13 months (huge risk of not backing up). I don't have to do things in sequence anymore, I just plug in or turn ON the USB dock with the SSD and flashdrive plugged in. It would mount flawlessly. Maybe there's a new Apple USB/USB-C/Thunderbolt/ driver somewhere that was on standby and it activated with the combination of the the external SSD and flashdrive when it saw that I had a fast external storage now and kind of rewarded things with the hardisk as well; even my hardisk is mounting when plugged in this USB dock. But still it took more than 1 year to backup and fix and the cost of the SSD which is 50% not cool, by Apple, though it's a blessing in disguise, a lot of time will be saved on SSD's efficiency which is worth it. The SSD prices have fallen I feel (at least for the 2nd tier brand that are still good but not that popular yet like Team Group) by 33% after a year. Though it's still under observation (I got my trusty High Sierra ready to boot in the Container on the same disk as backup OS and on another external drive- good thing Apple made the "macOS To Go" flawless with major upgrades, unlike Windows to Go, that why I only install Boot Camp internally).

Thanks. I hope it'll work for you (one can borrow and SSD maybe and a flashdrive)

 

[SweetumsTweet]

Just wondering if I'm just screwed until Apple fixes Monterey 12.6 or I can afford to replace my Macbbok Pro 2015 3.1 GHz Dual-Core Intel Core i7 . I just bought a new Seagate 5TB external drive, formatted for Mac HFS, did a timemachine full backup, tested it a few times with more time machine backups and all looked good before I made the jump from Big Sur to Monterey. I felt blessed that the install to Monterey went flawless and no weird freezes. Seems to work fine except it won't mount the new Seagate drive. Disk Util List in terminal doesn't even show it. I don't have any other Mac to test the external drive on to check that it's working. But based on the threads here, others have had similar issues although some had success with the Monterey 12.6.

So in addition to venting about a nice 5TB external I can't use unless I decide to reformat and lose my important backup, does anyone have any suggestions about how to get the drive to boot.

Thanks is advance for the free advice, wisdom and condolences. Cheers!

 

[Grumpus]

Just wondering if I'm just screwed until Apple fixes Monterey 12.6 or I can afford to replace my Macbbok Pro 2015 3.1 GHz Dual-Core Intel Core i7 . I just bought a new Seagate 5TB external drive, formatted for Mac HFS, did a timemachine full backup, tested it a few times with more time machine backups and all looked good before I made the jump from Big Sur to Monterey. I felt blessed that the install to Monterey went flawless and no weird freezes. Seems to work fine except it won't mount the new Seagate drive. Disk Util List in terminal doesn't even show it. I don't have any other Mac to test the external drive on to check that it's working. But based on the threads here, others have had similar issues although some had success with the Monterey 12.6.

When you boot to recovery (command-R) does the drive show up in disk utility there?

 

[Alvin777]

When you boot to recovery (command-R) does the drive show up in disk utility there?

Hi, mine doesn't, only the actual recovery drive is shown. Apple may have changed how Recovery works. I just installed another macOS Monterey on another storage to fix my system macOS if it needs it (I also have my trusty back up OS, the most stable macOS ever- High Sierra but eventually it won't support all the new hardware's benefits and it must be used to Disk Utility repair an OS higher than itself).

 

[Grumpus]

Hi, mine doesn't, only the actual recovery drive is shown. ...

In recovery, plug in the problematic drive, then run disk utility. Click View, then select Show All Devices. Does the drive (actual hardware) show up then?

 

[Alvin777]

Hi. They don't show up sadly even with Show All Devices. I wonder what Apple's up to.

Big Sur & Monterey seem to be guinea pigs/experimental OSes for something big and it's got a lot of "birthing pains"- I hope the file system they're up to is like Window's ReFS but bootable and only requires one drive.

If Apple is up to something, they should have an equivalent of Crucial's amazing 'Momentum Cache' (a 250MB/s became 2.4TB/s 16x faster on read & 1.2TB/s or 5x on write- it uses some RAM, some kind of RAM disk technique for SSDs. It'll scale faster on faster RAM for sure and faster M.2s, maybe a WD Black at 7TB/s with 'Momentum Cache' will become 35TB/s on write & 112TB/s maybe more w/ a next gen RAM). Samsung SSDs have an equivalent software.

 

[Grumpus]

Hi. They don't show up sadly even with Show All Devices. ...

A popular workaround in this Apple discussion thread is to connect drives using the usb-c to usb-c charging cable that came with the Mac - workaround and not solution since it limits data transfer to usb 2 speeds. Others reported success by unplugging Wacom tablets and other usb-connected devices, some by reformatting the drives to exfat.

 

[iDento]

Ok folks, I hope this may be of some help.

I'm running a 2019 iMAC and came in at OSX 12.2 with a SSD on board and Sandisk Extreme SSD drives for backups, as well as some WD HDD for backups. first thing I did when upgrading was to make a SuperDuper backup of my OS drive. It failed half way through the copying stage. I'll not bore you with the steps I took in my frustration but nothing worked. I got an error message saying the disk could not be found half way through the copy. It had disappeared from my desktop and had greyed out when viewed in disk utility. It was simply there and then it was not. Tried several times after rebooting and downloading a new copy of SuperDuper. I was using the latest release in any event, which said it worked with Monterey. Reaching out to SuperDuper I had a reply within a few hours and was asked if I was plugging the external drive into a hub? I was. One of those Satachi 'fit under the bottom of the iMAC hobbies. Have used it for years without any problems, so much so I don't so much consider it a hub but an integral part of my iMac. On the advice from SuperDuper I connected directly into the iMac's USB-C port by way of a rear entry. Ran SuperDuper and sat and watched every byte being copied over. It was faultless and worked like a charm. I discovered later that Monterey is not recognising many USB hubs on the market. Apple have apparently known about this since Beta and here we are at 12.2 and still a patch has not been released. For those of you who are finding your external drives not working either connect directly into your main connections or look out for a hub that is known to work. Chances are it is not the drive being rejected, but the hub.

I have the same issue, using a Satechi Slim Hub and WD NVMe disk. Unfortunately, I can not connect the disk Directly to the iMac because the hub itself is the enclosure.

 

[Alvin777]

I have the same issue, using a Satechi Slim Hub and WD NVMe disk. Unfortunately, I can not connect the disk Directly to the iMac because the hub itself is the enclosure.

Hi, if the NVME enclosure has a USB port, try plugging a USB flashdrive (if it doesn't try using the Mac's USB port), that seems to "shove" Monterey to mount the external drives (such a Huge bug, Monterey is the buggiest Apple OS ever made), try w/ cable unplugged, switch ON first, wait maybe 40 seconds then plug, or that and then the flashdrive is last to be plugged to hopefully "shove" things into mounting.

 

[iDento]

Hi, if the NVME enclosure has a USB port, try plugging a USB flashdrive (if it doesn't try using the Mac's USB port), that seems to "shove" Monterey to mount the external drives (such a Huge bug, Monterey is the buggiest Apple OS ever made), try w/ cable unplugged, switch ON first, wait maybe 40 seconds then plug, or that and then the flashdrive is last to be plugged to hopefully "shove" things into mounting.

Thanks for trying to help but, the disk disconnects when I copy data. Reading works fine, but writing anything more than 1 GB disconnects the drive. I hope it's a software bug and will be patched in Ventura. Both the hub and the disk are brand new.

 

[DJ Rob]

Figured I'd share my experience, since I'm having the same issues reported in this thread.

I'm using a 2020 MBP 13" Intel i7, so it's not exclusively an Apple Silicon problem. As @HobeSoundDarryl has stated several times, exact same drives with exact same cables works flawlessly on other systems running pre-Big Sur and never had the issue on this machine (originally on Catalina) until upgrading to Big Sur. And the problem remains unfixed.

I've tried all the *fixes* suggested here and elsewhere with no success. Does not matter who makes the drive, whether it's a hard drive or SSD, or which cable I use. Some drives I have are USB-C others mostly USB 3.0 Micro-B. I've tried TB cables, USB-C cables, USB-C to USB-A adapters, etc.- all connected directly to one of the TB3 ports on the MBP. All will disconnect within an hour or so (though I think disconnects are more prevalent during data transfers).

Only one thing seems to work for me: connecting through a hub. Not sure if it's *any* hub or I just got lucky, but the same combination of cable/drive that would disconnect when directly attached works fine if connected through the hub. The hubs I've had success with:

1. Monoprice 33508 Consul Series (I see it's now discontinued, so no idea if current models of the Consul series have same internals) Oh, and not using PD, so hub is powered off the MBP USB port.
2. LG 38WK95C monitor (one wire solution with USB-C from monitor doing PD to the Mac).

I'm at a loss as to why USB traffic through these hubs would be more robust than directly connected to the MBP, since the MBP still needs to handle the traffic from the hub, but maybe the hubs are converting the signals to something Big Sur/Monterrey prefers.

 

[Alvin777]

Figured I'd share my experience, since I'm having the same issues reported in this thread.

I'm using a 2020 MBP 13" Intel i7, so it's not exclusively an Apple Silicon problem. As @HobeSoundDarryl has stated several times, exact same drives with exact same cables works flawlessly on other systems running pre-Big Sur and never had the issue on this machine (originally on Catalina) until upgrading to Big Sur. And the problem remains unfixed.

I've tried all the *fixes* suggested here and elsewhere with no success. Does not matter who makes the drive, whether it's a hard drive or SSD, or which cable I use. Some drives I have are USB-C others mostly USB 3.0 Micro-B. I've tried TB cables, USB-C cables, USB-C to USB-A adapters, etc.- all connected directly to one of the TB3 ports on the MBP. All will disconnect within an hour or so (though I think disconnects are more prevalent during data transfers).

Only one thing seems to work for me: connecting through a hub. Not sure if it's *any* hub or I just got lucky, but the same combination of cable/drive that would disconnect when directly attached works fine if connected through the hub. The hubs I've had success with:

1. Monoprice 33508 Consul Series (I see it's now discontinued, so no idea if current models of the Consul series have same internals) Oh, and not using PD, so hub is powered off the MBP USB port.
2. LG 38WK95C monitor (one wire solution with USB-C from monitor doing PD to the Mac).

I'm at a loss as to why USB traffic through these hubs would be more robust than directly connected to the MBP, since the MBP still needs to handle the traffic from the hub, but maybe the hubs are converting the signals to something Big Sur/Monterrey prefers.

Thanks (I have a feeling Apple is preparing everyone to not use any USB tech in their next  Silicon M3 next year and could be going propriety which would be faster than the next USB 4 and won't use anything related to USB, like the USB-C port, perhaps to cut costs from USB licensing fees (and logo). I feel they'll use a faster than USB 4 propriety Thunderbolt 5 w/ lightning connector coz' that seems smaller, flatter & cheaper to make, completing the all designed by Apple transition. All Apple from the CPU, GPU, RAM and I feel even the SSD all in SOC but w/ RAM support so it doesn't wear out like Crucial's 'Momentum Cache' which makes the storage bandwidth x8 to x16 or more faster X-D. This'll beat any GTX 4090 ITX equipped PC which'll prompt the death of the PC or diminish its market share, once Boot Camp Windows ARM God willing is on the Mac Silicons). The external drives that has USB tech (be it Thunderbolt 2/Display miniPort to USB 3 w/ USB-C, like a slot machine, mounting or not mounting (same with the image like .dmg), I think Apple dropped improving the drivers for anything USB which makes it picky w/ brands and/or models of external drives. Apple will mostly sell dongles for it so the USB external stuff can still be used or may not (just like the first iMac which was USB only but that made the world move on from parallel and serial which were slower and used more raw materials to manufacture. Apple's 'what's good for the world, sometimes customers don't know what they want' mantra is a double edged sword in the short term).

Though my guess is after testing it w/ their portable and their new wireless charger tech for the iPhone 14 (uses magnets to align things) they would even go cableless (will save them manufacturing money again) so there's no more problems w/ charger waste on landfills and EU problems and will most likely use 6G Wifi which'll be faster than any next gen USB 5 nor next gen Thunderbolt (version 5) or even Wifi 7 which is only 46Gb/s. 6G Wifi does 8000Gb/s or 1Terabytes/s data transfer- huge raw material savings for Apple and again will lessen pollution (we have a lot of broken cables and obsolete chargers at home if we've observed). Most likely receivers for it will be offered for USB & Thunderbolt but will need to be powered hubs. I wouldn't be surprised if they partner w/ Elon and SpaceX so it's all Wifi 6G but w/ satellites to simplify seamless integration w/ the  Watch Ultra (and  Car maybe

This is why I think Apple has not updated it's Thunderbolt/USB external storage drivers (and image mounting, maybe they'll change the image mounting system as well, wherein there's no need for compression as an image, the file is already at it's most compressed all the time; if it's an app we just launch it without mounting or uncompressing and the system just prompts you if you want to put the whole app of file in the proper folder) for Monterey (or very little changes).

By the way, how about external drives that are on Thunderbolt 1 of 2/Display miniPort (doesn't use USB tech yet), do they always mount (but then images, be it .dmg, iso and the like also don't mount if external storage don't mount, it seems to not be just an external storage driver issue but a mounting problem in general. A key maybe found on FastDMG which I used to mount images like .dmg as mentioned before, so I can install things. How's that working to force mount images? I hope the FastDMG dev makes a force mounter for external storages at least until Apple fixes this major bug, if it's a major bug for them that is and is not another USB like transition like in the iMac)?

Thanks have very blessed sunday.

 

[daveg999]

I doubt I can add anything that has not been mentioned before - except this problem only stated for me with Monterey. I have both Intel and Apple Silicon machine. I have maybe 15 external SSD's - mostly but not all Sandisk. I typically use Carbon Copy cloner for backups. What happens is that CCC will one day really slow down when backing up files. Now I have noticed that my external Sandisk 1GB Extreme drives are way way more likely to experience this issue than my Sandisk 2GB Extreme Pros. Lets say my 1GB drive normally backs up a 500mbs. When this problem occurs it will drop to 30mbs and no amount or rebooting / disconnecting and reconnecting will fix it.

So this is what I have found will restore performance for a while.

Basically I re-format the drive - but that in itself can be problematic. Often I reformat as MS-DOS, then reformat a APFS. Frequently the process will hang on first format and I will have to disconnect the drive and start again. I suspect some other process is holding the drive open which causes it to freeze up.

Anyway - once I have formatted back to APFS the drive will once again fly along at full speed - but it never lasts. I will eventually have to repeat the process.

I spent many long hours exchanging emails with Sandisk which basically blamed Apple - once admitted it was a known problem - but then denied that. I got so frustrated with them I gave up.

I did purchase some newer non Sandisk drives which so far have been more likely to behave.

Now most of my drives are SSD's but I do have 2 regular HD's and these are used for time machine. It's harder to tell with time machine what the speed is as it's not very informative - but generally I don't have to mess with those drives very often.

It's most frustrating and I suspect its a combination os MacOS and some drive firmware which makes this issue more likely to occur. Thats why some people claim it's not a bug - because they are using a lucky combination.

Ventura seems to suffer as I'm formatting a drive again as I type this.