I noticed when trying to reach www.freebsd.org the last week on a mac that it took forever, just sitting there spinning on an empty page. But on the same network in loaded right away on a Windows XP system. I thought that was rather odd, but moved on and didn’t think about it again until last night. I tried it again and noticed the same problem, using any browser on the mac it never loaded, on Windows XP showed up right away.
That’s when a little inspiration showed up. I knew that www.freebsd.org was also available via IPv6, I wonder if Mac OS X was trying to reach it via IPv6 first. If it was then it would never succeed as my DSL provides IPv4 and I don’t have a IPv6 tunnel setup. First I confirmed that www.freebsd.org had an IPv6 address, host www.freebsd.org provided this:
[sourcecode highlight=”2″]
www.freebsd.org has address 69.147.83.33
www.freebsd.org has IPv6 address 2001:4f8:fff6::21
www.freebsd.org mail is handled by 0 .
[/sourcecode]
The second line there confirmed that there was indeed an IPv6 DNS address for www.freebsd.org.
Next was a quick trip to the network preferences on the mac. Click the ‘Advanced’ button for your network connection and under the TCP/IP section you’ll see an option labeled ‘Configure IPv6’. Mine was set to ‘Automatically’, which I then changed to ‘Off’. Click ‘OK’ then ‘Apply’. That turned off IPv6 support for my network connection on the mac.
And sure enough www.freebsd.org loaded up right away again after that.
If you aren’t using IPv6 on your network then it’s probably worth just turning it off. I’m rather surprised that I didn’t run into this sooner. I guess there aren’t that many websites out there advertising IPv6 addresses.
Update: I noticed that us2.php.net has an IPv6 address listed as well, which explains why I’d had problems loading that site too.
6 replies on “Slow Loading Websites in Mac OS X Web Browsers”
It worked for me with IPv6 set to “Automatically”. I guess my ISP supports IPv6 then?
Interesting. I wonder if there is another option some where in Mac OS X to tell it try IPv4 addresses first instead of IPv6.
All of the routing hardware from your computer to the web server need to support both IPv4 and IPv6. If any part of the chain cannot properly route IPv6 traffic, you’ll have problems.
One way to avoid those problems is to setup a tunnel, which I believe is essentially a way to go through IPv4 hardware to a specific IPv6 hardware device that then completes the IPv6 connection to the web server. The other way is to have all of the hardware be IPv6 compatible.
I am unaware of any services or sites yet that are IPv6 only but almost all network infrastructure hardware have supported both IPv4 and IPv6 for a number of years now. I wouldn’t be surprised if your DSL modem and beyond already supports IPv6.
I bet the problem is your router. To test, you could try connecting the MAC directly to your DSL modem with the setting in OSX back to ‘Automatic’. If the site loads right up, then you know the problem is your router. If that works, I’m going to be shopping for a new router for my network!
I don’t think there are many DSL providers out there supporting IPv6, and I’m quite sure that Qwest isn’t 🙂
Setting up an IPv4 IPv6 tunnel has probably gotten easier since the last time I did it seven or eight years ago. But at this point I don’t have much demand for that.
Just curious, but this tip (turning off ipv6) seems to have (so far) fixed an issue that I’ve had for a long time. The sites would sometimes open very slowly, unless I nudged mail to check for new mail. THEN the site would open right away. How is that related?
Not sure, they don’t seem related.