This morning, Apple released new OS X, Yosemite, to developers. I’m so excited that I’m now using it. :D

I’ve met some problems after the upgrade.

Stuck in the installation when 4 mins left

For me, it lasted around half an hour for the last “4 mins”. Checking the logs by ⌘-L showed it actually was doing something, which comforted me.


It asked you to reboot the computer to make it work, which couldn’t. According to PCKeyboardHack issues 31 and I’ve tried, this command actually works.

sudo kextload /Applications/

Before official support released, I’ll live with this trick.


I installed dnsmasq by homebrew and it was daemonized by launchd. In Yosemite, launched was updated, and a new concept added (if not added before), which is domain. Also, new subcommands are replacing the old ones.

Whatsoever, somehow, dnsmasq didn’t get started at load, and the usual command to start it doesn’t work: launchctl load /path/to/homebrew.mxcl.dnsmasq.plist. The workround is to use subcommand kickstart. To reload,

sudo launchctl kickstart system/homebrew.mxcl.dnsmasq

system is the domain, which is needed for processes to be run as root.

update: Thanks to Chuong Dang, there is a way to run it at boot. It’s to add RunAtLoad to the plist.

The plist will be

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "">
<plist version="1.0">


Some weird issue after fixing the ruby version and installing command line tool, saying things are missing.

Actually the path is not complete, without pathes with brew. I don’t know how it works before, but adding argument --env=std fixed the problem.

DNS cache

Previously, I used sudo killall -HUP mDNSResponder to flush dns caches, but somehow mDNSResponder doesn’t get started, so I found the new tool discoveryutil, and to flush dns caches, use sudo discoveryutil mdnsflushcache.

Audio doesn’t work after sleep and wake

sudo killall coreaudiod to restart audio deamon, but iTunes has to be restarted to make sound.

Ctrl+number doesn’t work to switch desktops

killall Dock would do the trick.

note: minimized windows will appear.