Where are crash logs after a system freeze?

Question

When your entire macOS freezes up and restarts, are there crash logs or core dumps to diagnose the problem? I would in particular like to know which kernel module was active at the time of the crash.

Symptoms: The display "froze", the mouse cursor stopped moving, and the Force Touch trackpad stopped doing clicks. After maybe 10-20 seconds, the system restarted on its own. When it came back up I expected to see a Crash Reporter dialog, which usually has some useful details on the crash, but there was none. I also looked through logs in the Console and couldn't find anything, though maybe I missed something. Is there some place where I should expect to find crash logs?

Answer 1

Apple moves the logs from version to version, but I would start with sysdiagnose.

Open the terminal app and type sysdiagnose or press the keys to trigger the data collection process.

• How do you get system diagnostic files from OS X?

The good thing about this is it collects both the traditional log file based logs, snapshots like recent crashes, panics, hangs as well as a recent sample stored in a potable log archive format of the system log database files (since 10.9 more and more logs are stored in the apple system logs database as opposed to flat files and panic logs).

From there, you can open the file and search for the panics and crashes.