What went wrong?
30 Oct 2018
Okay. So I had a problem with my Mac. Basically, about 10 minutes after a restart, the application switcher and the dock would stop working. Whichever application I had at the front (chrome, terminal, editor whatever) would be fine but I won’t be able to load or change to any other application. Alt-Ctrl-Esc would work, so I could kill applications, but that wasn’t particularly helpful.
The cause of the problem took FAR TOO LONG to track down. It was apache. More specifically, I had installed Homebrew’s Apache and the built-in version of apache hadn’t been disabled properly, so they both started up on a reboot. NO IDEA why this broke the dock.
(Note: I had setup apache using this guide macOS 10.14 Mojave Apache Setup: Multiple PHP Versions – and thank-you grav people, very helpful.)
If I killed all the httpd processes (sudo pkill httpd) immediately after the restart, and then restarted apache I was fine but that wasn’t exactly a longterm solution.
This command should stop the running instance of Apache, and record that it should not be restarted.
sudo launchctl unload -w /System/Library/LaunchDaemons/org.apache.httpd.plist
But it gave the error:
/System/Library/LaunchDaemons/org.apache.httpd.plist: Could not find specified service
Basically, the native OSX instance was still running, but it had become separated from launchctl, so launchctl couldn’t unload or stop it.
First of all, I took the brew apache out of the picture
brew unlink httpd
Then try
which httpd
This showed /usr/sbin/httpd Okay, we can now FINALLY see the OSX apache. Try restarting it.
sudo apachectl restart
It gave this error:
Address already in use: AH00072: make_sock: could not bind to address [::]:80
That’s my problem. Because of this error, the apachectl process would start up, but the launchctl couldn’t shut it down properly.
A little bit of headscratching, but fixed by editing the apache config file (for OSX, not brew apache) /private/etc/apache2/httpd.conf and setting:
ServerName 127.0.0.1
Now the command sudo apachectl restart works. And sudo launchctl unload ... also works.
Restart the mac, check the processes and (hurrah) no httpd processes found.
Link brew version back up.
brew link httpd brew services restart httpd
Normality restored. But it took me a long time to get there.
Pretty sure all this kicked off when I upgraded to Mojave 10.14.
TL;DR launchctl thought it had properly shut the apache process down, but the apachectl agent refused to stop because reasons, resulting in a decoupled process