We have a 128 TB Thunderbay 8 on SoftRAID 7.0.1. Ever since Big Sur, our 2017 iMac Pro has been crashing at shutdown and automatically rebooting. We then see the "Your Mac has been restarted due to a problem" message. We are currently on Monterey 12.5 and the issue still happens. We are aware of the known issue regarding the Mac kernel bug that causes the Mac to crash when there are a lot of large drives attached. I expect that this is what is happening. If you count all 8 drives in the Thunderbay enclosure, our Time Machine drive, and a few other drives, that comes to nearly 12 or so. I have tried ejecting (unmounting) ALL drives prior to shutdown (but not physically disconnecting them) but the Mac still crashes and reboots with all drives ejected. The only way we've found to get the Mac to shut down properly is by ejecting the Thunderbay 8 enclosure and then physically powering off the enclosure using the power switch on the back. As long as the Thunderbay 8 is physically connected and powered on (ejected or not), the Mac crashes and reboots. We really would rather not have to physically power off the enclosure every time we want to shut down the iMac Pro. This is especially a problem when we schedule the Mac to automatically shut down at a specific time and we are not around to eject and power off the Thunderbay 8.
I have included two panic logs (one from when all drives were mounted and then a second after attempting shutdown with all drives ejected) and our SoftRAID 7.0.1 support file for your review. We are hoping that there is a solution by now to avoid this shutdown crashing problem. Thank you very much.
This bug has been partially fixed in Ventura, if you can upgrade MacOS. Apple increased the Time out for how long it takes to flush the cache on every disk. So Ventura solves a lot of these issues. Since this is a MacOS shutdown bug, we cannot code around it.
I just upgraded to Ventura on the iMac Pro. Unfortunately, this did nothing to resolve the problem. The Mac still crashes and reboots with the Thunderbay 8 attached and powered on even though it and all other drives are ejected in Finder. The workaround that was previously provided in the SoftRAID Known Issues was to eject all of the drives prior to shutdown. Why does the Mac still crash and reboot after I have ejected all external drives?
@midihead7
whatch the computer drives when you shut down. You will see one drive at at time with its light on for a couple seconds, then the next, etc.
This is the cause of the problem, as if all drives flushed their onboard cache at the same time, no problem, unless there was a faulty disk.
however, with lots of drives, this flushing of the disk cache can crash the symptom if it takes too long, which is the watchdog timer. Apple's "fix" was to increase this time, not to fix the synchronous flush (one at at time.)
Look at the crash report. this will happen regardless of what disk format the disks have, Apple, SoftRAID, windows, or whatever, as it is a hardware trigger, not a SoftRAID or disk driver that triggers this.
We all know no one ever has more than a few external drives, right?
My last question was why my Mac still crashes even though I have ejected all drives first. This was supposed to be a workaround according to the SoftRAID Known Issues. Do you have a clear answer for this please?
Since the workaround doesn't work for me in Ventura, will powering off the Thunderbay 8 after ejecting the enclosure hurt anything while the Mac is still on? The 8 drives all make a loud click when I do this so I'd like to be sure this doesn't negatively affect the drives or the data. Thanks.
Because MacOS still knows the disks are there and sends a "flush cache" command to each one. it would not matter if they are unmounted.
the click is the heads unparking. If you wait 30 seconds or more before powering them off, no harm is done to either the disks, or your data.
(You may be able to get away with just powering off one of the enclosures)

