How do I refresh the hosts file on OS X?

I'm trying to develop using subdomains on OSX but don't want to reboot the computer to refresh the hosts file. Normally on linux I'd do /etc/init.d/networking restart but I can't figure out how to do this on OSX.

Solution 1:

You don't need to. Simply sudo vim /etc/hosts, change what you need to change and go on. Your changes will be applied instantly.

If ping yourdomain.com still gives you the wrong IP, try clearing your DNS cache:

OSX 10.4 and below: lookupd -flushcache
OSX 10.5 + 10.6: dscacheutil -flushcache
OSX 10.7 + 10.8: sudo killall -HUP mDNSResponder
OSX 10.9 and above: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
OSX 10.12 and above: sudo dscacheutil -flushcache

Solution 2:

For macOS El Capitan (10.11), go to the Terminal app and type:

sudo killall -HUP mDNSResponder

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