Experts: Mac Mini having a hardware or software problem?

Factual Questions
1

I have a Mac Mini (late 2012 model). It has an internal SSD and 16 GB of RAM. The entire thing was built by Apple and has never been opened since I bought it. It is running the latest Mac OS.

A few months ago, I started having an issue where when it booted, the Apple logo would appear and the status indicator under it would only progress to the middle and stay that way. The Apple Trackpad would still work if I moved it around, but I even let it sit this way for 30 minutes and it never finished booted. It usually boots in about 30 seconds. When it would act this way, I would hold the power/boot button in the back until it would power off. Then I would boot it again and it would always come up without a problem, but it would have a message referring to that it wasn’t shutdown correctly.

I contacted AppleCare and they had me do the normal things like reset the PRAM (NVRAM) stuff, reset the SMC, run Disk Utility and run Hardware Test but it never showed there was a problem with the system.

I have a Linux background and knowing that the Mac OS is built on UNIX, I decided to look into this further. However, I don’t know the internals of the Mac platform that well, so I can’t be sure I am even looking in the right place.

So I logged into the Terminal application as ‘su’ and did a ‘cd’ to /var/log and found the ‘system.log’. I’m looking in here because I am wondering if there are error messages that would reveal something hardware wise or whatever might be causing the problem.

Nothing really jumped out at me. If it could be an intermittent SSD problem, then I would expect to see something about that device in the error logs as a problem. But I still don’t know if I’m looking in the right place for this or what it looks like to determine if it is an SSD problem.

The fact that when it finally gets to come up, it knows there was a problem that it wasn’t shut down properly indicates to me it got far enough in the boot to start running the OS at least on some level. Could it be software that is causing the problem? Or the SSD?

It could be the power supply, but would there be an error message about that? This system is connected to a UPS, so the voltage coming in is stable.

I am considering wipe the drive clean and doing a fresh install and see if that takes care of the problem.

My gut feeling is that the SSD is flaking out, but I’m not sure which log would contain a message about it and what it would say. I did a ‘grep’ for the words ‘error’ and ‘failed’ but they usually refer to things which appear even on a normal boot. The only thing that referred to a device failing said something about USB, which the only USB things connected are a keyboard and the Viewsonic monitor’s hub, and a Samson Go Mic.

I was having this problem before the major upgrade to Mac OS X El Capitan.

2

I’d start out by booting in verbose mode to see where in the boot sequence it is hanging. Instructions here:

https://support.apple.com/en-us/HT201573

3

Thanks, that’s a good idea! So each time I need to turn on the machine, I will give this a try. Hopefully, it will reveal something useful.

4

before you do anything else, download and run the latest combo installer update again. That often fixes things if you have a corrupted system file somewhere.

https://support.apple.com/kb/DL1850?locale=en_US

5

System software is up to date. That would have been downloaded as part of the normal software updates.

I’m surprised I can’t find articles about reading the Mac OS X logs to determine hardware errors or problems with the SSD. Perhaps I am overlooking something in my Google search for that or it is such a rare thing, people don’t troubleshoot this way on the Mac?

6

The logs are laid out in logical fashion. Just look at the System log (all messages) to see any errors. You will see the boot sequence in the log, and can follow that to note any serious errors.

If you think you have a drive problem, look in Disk Utility and check SMART status.

But, booting into Verbose mode is the way to go.

7

I’ve run Disk Utility and the hardware test including the long one, and it never complains about the hardware. The problem with an SSD, is that it has no moving parts so it doesn’t make a sound if it is having a problem like a hard drive.

I don’t see anything that appears to be device related for the SSD in the logs, but I don’t know what that message would look like for the Mac. I’m assuming it would have words like error or failed as part of it. I see something like this, but no idea if it is related:

Dec 25 00:33:19 localhost kernel[0]: init: error getting PHY_MODE; using MODE_UNKNOWN

8

Have you done the Verbose boot yet?

9

Yes, I sure did, thanks. The problem is intermittent, so it has not recurred yet. I found this article:

So I don’t have to hold down the keys each time, which makes it easier.

I’m wondering if when this done happen again with verbose boot on, if it will actually display a message when it gets stuck. The way it is now on normal boot, the messages fly by but once the Apple logo appears the verbose messages aren’t displayed.

I wish I knew when the status indicate bar is right in the middle under the Apple logo which the system is processing at that point. The Mac OS must be up on some kind of run level because it knows it isn’t been properly shutdown the next time I boot it.

I’m trying to recall at least with Linux systems, if an intermittent problem on booting was ever caused by something on the file system.

10

Typically a big hang on the boot progress bar is caused by fsck repairing directory corruption.

11

Yes I know you are up to date but in my experience downloading and re-installing the latest combo update again over the top has fixed similar issues on my own machines in the past. The combo installer will overwrite any corrupted files as well as doing a bunch of other tweaks. Try it.

12

Have you reset the NVRAM?

13

I let it sit/run for 35 minutes once when it hung. The SSD is 256GB. Since ext4 a fsck shouldn’t take that long to run. In the system.log file when it runs fsck it finished and only last a few minutes at most.

14

Yes, I’ve reset NVRAM. Also SMC.

15

Wouldn’t corrupted files show up in a Disk Utility First Aid? Has this cured intermittent problems for you?

16

The next thing I’d do would be to open the Mini and make sure the cooling isn’t blocked.

17

You might want to get a copy of the disk utility DiskWarrior. Even if that doesn’t fix the problem, it’s a handy tool to have around.

If you don’t want to spend money, I’d second the recommendation of applying the latest combo update which is here. Running the combo update is a traditional catchall fix for Macs. It’s part science, part voodoo. Maybe one day the combo update will go the way of rebuilding the desktop, but until that day…

After that, I would do the clean install. And then get DiskWarrior.

18

I didn’t even know they still were making and supporting DiskWarrior. I’ve not heard it mentioned in years so I assumed it wasn’t necessary anymore. Thanks, I will have to check it out.

19

After going through AppleCare who decided to replace the logic board, I am still having the intermittent problem on boot where it hangs at the Apple logo in the middle of the status indicator bar. AppleCare then wiped out the system and installed the latest Mac OS which is 10.11.3. Running it in verbose mode didn’t reveal anything. I guess verbose isn’t available during this part of the boot sequence.

The problem happened again today. I was working with it today, did a shutdown and when it tried to boot up, it stopped under the status bar for the Apple logo.

There is something about this that doesn’t make sense to me in the Console logs. I left the system at this point and called AppleCare. It stayed in this exact position for 42 minutes until I forced to power it off. I then booted it up which booted as normal at 4:25 PM. When the system was in this odd stage where it wouldn’t finish booting, it fully recognized the bluetooth trackpad magic mouse and I could move the cursor around. During that 42 minutes the screen energy saver thing kicked in and put the display to sleep. When I would move the mouse it woke it up, but it still was stuck at the same spot and didn’t finish booting.

Here is the part that doesn’t make sense in the Console logs, is the time line. If the system was indeed stuck, I’d think it shouldn’t be updating the logs at all or very much. But that doesn’t seem to be the case. It continued to update the logs during those 42 minutes while the thing was stuck on the screen. I guess since it knows about the mouse and allowed me to move the cursor around and the energy saver thing did put it to sleep and did wake it up, then it must be at some kind of run level, but not finished enough to bring up Finder.

The only software I have installed since I got this back after Apple wiped it clean with a fresh Mac OS, were things like Open Office, Veracrypt, Firefox, Google Chrome, iMovie. I re-installed Smulton which I had purchased previously from the Apps Store. For those that don’t know, it’s a text editor.

AppleCare over the phone guessed it might be a power supply problem or that the replacement logic board is faulty and needs to be replaced again.

This is a Mac Mini (late 2012) with 16 GB of RAM and a SSD, as shipped from Apple.

My big disappointed is that I can’t get anyone at Apple to look at the Console logs. They looked at the Crash Logs only, which don’t reveal anything. I know Linux logs, but Apple internals are a mystery.

I will be taking it into the Apple Store again and it is under warranty. What should I be asking them to do? I don’t want them to run hardware diagnostics which never reveal a problem on this system and then send me on my way. Should I ask them to replace the logic board and the power supply? Or something else?

I had this problem before upgrading to El Capitan. I was hoping that El Capitan would fix this problem, but it didn’t. I have been using this system every day since I bought it in 2012 and until the last part of 2015 never had a problem with it.

20

Odd to say the least.

Logs are nothing special - /var/log/* with older logs archived to .n.gz

/var/log/system.log should hold pretty much anything you want. Just look at the end. It is not a great deal changed since Unix of the 80’s. Crash logs contain stack dumps and possibly binary dumps. They would probably be looking for traces of known issues.

However you haven’t replaced the SSD?

The system is fully up before the finder is running. Finder is just a user level application that runs under the logged in user. The mouse and keyboard drivers are brought up very early in the boot, probably at about the same time as most of the other devices. You need the mouse or keyboard to select which image to boot the OS from, so they will be configured before the boot has even found a disk drive.

If you grab a limited set of console log, you could post it here. Someone may have an idea. Little more than 100 line from the start of the boot should find it.