I recently had a problem connecting via wi-fi at a local restaurant. This is how I solved it.
Apple’s OS/X 10.9 Maverics seems to have produces many networking problems for people, myself included.
This particular problem arose when I was at a local favourite restaurant that offered wi-fi connectivity. I haven’t encountered this elsewhere (yet), but I’m cataloging this so if others encounter the problem, this might be one way to fix it.
Networking could find the wi-fi and it would connect to the WAP, but it would not connect through to the Internet.
Initially, I thought it might be the WAP/Router/Modem in the restaurant, but when I tried to connect with my smartphone to the wi-fi, there was no problem getting through.
When I looked at the connection on my phone, I noticed it had an IPv4 number, while the mac was trying to connect using IPv6.
The symptoms were that the wi-fi would connect, get an IPv6 number, then in a little bit would fail-over to a non-connected IPv6 number. The IPv4 number coming was the default internal IPv4 number, showing no connection.
Turning off IPv6
It used to be easy to turn off IPv6 in future versions of OS/X. I’m not sure when it disappeared, but you cannot simply turn it off via the System Preferences Network Pane anymore.
A quick search of the web provided an answer:
The thing to do is to use command line to turn it off:
networksetup -setv6off wi-fi
Turning IPv6 back on
It is probably not a good idea to leave IPv6 off for any particular interface, so turning it back on is another command line:
networksetup -setv6on wi-fi