Hello all,
We have an environment with many identical 27" Fusion-drive iMacs (Late 2014). We've had a reoccurring issue with these machines that I can't seem to figure out. When rebooting they more often than not stall out on the loading bar and just go to a black, unresponsive screen. We then need to force shutdown.
It will keep rebooting into that black screen until someone boots it into verbose or single-user mode. Usually you have to try about 3-4 verbose or single-user boots to kick it back into a regular login cycle where it actually reaches the login page.
The only somewhat helpful message in verbose boot is related to DYLD cache:
Oct 11 16:19:17 localhost kernel[0]: Sandbox: launchd(1) System Policy: deny(1) file-write-unlink /private/var/run/dyld_shared_cache_x86_64h
Oct 11 16:19:17 localhost com.apple.xpc.launchd[1]: Failed to remove file or directory: name = dyld_shared_cache_x86_64h, error = 1: Operation not permitted. Further logging suppressed.
When it stalls in verbose boot it tends to stall right after "SDXC: pause". System.log shows this coming up after that (not displayed in Verbose boot)
Oct 11 16:17:45 localhost kernel[0]: Sandbox: launchd(1) System Policy: deny(1) file-write-unlink /private/var/run/dyld_shared_cache_x86_64h.map
I have re-imaged all of the affected computers (using fusion drive utilities in DeployStudio, laying down a 10.11 image). After the image they all worked splendidly for ~1 month, and this week a few have cropped up with the boot to black screen issue once again. I'm worried it will start affecting all machines again.
Wondering if anyone else has experienced this issue. I have not noticed the problem on other machines in any of our other labs. I think this may be the most highly used batch, and probably only 1/2 labs with fusion drives. Other than that I can't think of any major differences.
Thanks all.
