Mac sometimes ejects external SSD during sleep

[gradi]

My 16" M2 Pro MBP 32gb/1tb (Ventura 13.6 now, but happened on 13.5.2 also) has an external 4tb SSD connected all the time. About every week or so when it wakes up from sleep I will see these 2 messages on the screen:

As I said, it only happens infrequently, but it has happened 4 times in the last month. I unplugged the SSD and plugged it back in to see if it would mount, but it does not.

System Settings > Battery > Options... > Put hard disks to sleep when possible is set to Never. Same result when set to Always.

I ran Disk Utility and First Aid and got this:

Fortunately, I also have a Windows laptop so each time I have this Mac problem I plug the SSD into the Windows laptop and run chkdsk to see if there is a problem. Each time chkdsk reports no problems. Then I plug the SSD back into the Mac and this time it is mounted and all is well. I suspect Mac is erroneously setting a flag or something that says the SSD has a problem and the Windows chkdsk after determining there is no problem unsets the flag.

The result of this Mac problem is that now I must keep a Windows PC nearby to fix the Mac problem. When I go on a trip with the Mac I must also carry my Windows laptop. Ridiculous.

Anyone have any ideas?

 

[Bigwaff]

What is the file system on the external SSD? I'm guessing ExFAT since you seem to be able to write files to it from the Mac and run "chkdsk" on it from the Windows PC. If the external SSD is used exclusively on the Mac, consider reformatting it APFS, Apple's preferred file system format for SSD storage. I would trust Disk Utility to certainly handle repairing APFS disks vs a non-Apple file system format like ExFAT.

 

[gradi]

Thank you for your reply.

Yes, exFAT because I need to use on both. It is one of the Apple supported and approved Mac file systems:

https://support.apple.com/guide/disk-utility/file-system-formats-dsku19ed921c/mac

Anyway, please let's try not to change the subject of this thread. I am wondering about the 2 problems I wrote about:

1. MacOS occasionally ejects my SSD for no apparent reason.
2. After MacOS does this it apparently erroneously indicates there is an error so it cannot mount it. But after Windows chkdsk verifies that there is no error MacOS then happily mounts it again.

So, if someone knows how to prevent MacOS from randomly ejecting the SSD occasionally (but most of the time does not) then that would be great.

And, if someone knows how to make MacOS and Disk Utility to work properly with an Apple supported and approved Mac file system on my external SSD then that would be great too!

 

[HDFan]

So, if someone knows how to prevent MacOS from randomly ejecting the SSD occasionally (but most of the time does not) then that would be great.

There are hundreds of posts about unexpected ejections. No general fix that I have seen. Some times it is fixed by changing the enclosure. The only workaround is to eject it before putting the system to sleep.

 

[askme]

Yeah, this has been happening to me since Ventura with both APFS and HFS+ formatted drives, haven't been able to work the reason unfortunately.

 

[HobeSoundDarryl]

This is known issue since Big Sur. I've pounded this problem to death to try to DIY fix it and arrived at the conclusion with pretty good confidence it is bugs in port management and/or power management software in macOS. There is no fix except to try different enclosures and basically get lucky with one. Some work. Some don't. It's not brand based (some of one brand work, some won't). It not age based (some ancient drives I pulled out of retirement remained connected vs. fairly new ones that would not). HDDs seem more affected than SSD, RAID setups more than single drive enclosures.

Apple fans are likely to drop in to blame it on all things not Apple: cable, enclosure, firmware, hub, powered hub and even the user. But there are plenty of threads about this already- including on Apples own support forums- with people working through all such suggestions (as I have myself) to no remedy.

If you really dig in you can find examples of people with Mac running macOS BEFORE Big Sur having a perfectly functional enclosure. They upgrade macOS and- all other variables remaining the same- they suddenly have this issue. SOME of them need the reliable storage more than the macOS upgrade so they downgrade... and all is fine again. To me, that SHOUTS where the issue lies.

Try different enclosures until you find one that can stay connected. If that 4TB is m.2, I landed on OWC Ministack STX. It's not a speed demon at all but gives me both a 8TB m.2 and 22TB HDD connected with no ejections for over a year now. Buy, put your 4TB m.2 in there and you'll probably cease the unexpected ejections.

Many think it is tied to sleep but I've had drives unexpectedly eject while reading & writing from/to them, so neither end is asleep. Some apply an app called amphetamine which basically keeps the drive awake 24/7 (conceptually wearing it out sooner than it should) and that has worked. I have not tried that as I just opted to (hopefully) temporarily retire my RAID HDD enclosure and re-test it with macOS updates.

If you take the "won't stay connected" drive and hook it to an older Mac running pre-Big Sur or any PC, odds are very high that all will be fine again with the drive. Bring it back to the new Mac running macOS Big Sur or newer and it will resume the ejections. I miss "just works" Apple.

 

[eRondeau]

The Realtek firmware on your external USB drive needs to be updated. Please see this thread:

https://forums.macrumors.com/threads/usb-c-connection-dropping-external-nvme-ssd.2272502/?post=31359517#post-31359517

 

[gradi]

Thank you to everyone for the replies. It looks like there is no solution. This is just the latest Mac problem I have had after owning 4 Apple Silicon Macs -- various MacOS bugs that never get fixed. I am missing the old days when I used computers that just worked: my various Windows laptops.

I cannot change enclosures because I did not build my own SSD. It is an external SSD I bought. Lots of companies sell them already built: Sandisk, Crucial, Samsung, etc.

 

[gradi]

The only workaround is to eject it before putting the system to sleep.

If I eject it before the Mac sleeps is there a way to remount it without having to physically unplug it and plug it back in?

This seems like a difficult workaround since, of course, the MBP will sleep at other times than just when I select sleep. For example, it is normal for it to sleep after a period of inactivity. Probably that can be disabled, but I don't want to disable that.

 

[HobeSoundDarryl]

Switch to something else that will stay connected and retry that one from time to time after macOS updates. I'm hopeful Apple will eventually deal with this issue but its been years now (since it started in Big Sur) so my own hope is dwindling... and I'm shopping for alt enclosures myself.