Flush DNS OS X Yosemite 10.10.4 – discoveryutil command not found

With the recent update of OS X Yosemite to 10.10.4, the usual way of flushing the DNS using discoveryutil no longer works.

$ sudo discoveryutil mdnsflushcache; sudo discoveryutil udnsflushcaches
sudo: discoveryutil: command not found
sudo: discoveryutil: command not found

discoveryutil has been replaced by mDNSResponder in 10.10.4.
The following command should clear the DNS cache.

sudo killall -HUP mDNSResponder