Thanks and Happy New Year.

Impressive comment!

In response to your questions:
1. It appears that adding the DNS server in network preferences under one account applies to all accounts. Is this correct? (Note that if you change the IPv6 setting in Firefox that must still be done for each user account).

Yes, I believe DNS settings are a system wide setting that are set in place even without anyone logged in.

2. If I wanted to I could still use the DNS provided by my ISP by specifying that server instead of or in addition to the OpenDNS servers, correct?

Yes you can still use the DNS provided by your ISP as a backup. Multiple DNS entries will be used in reverse order, i.e. last DNS server entered will be the first tried when performing name to IP lookups.

Ben

I now have much faster internet again! Thank you so much for this help. Many other sites explained the problem well enough, but only this site gave a working solution! Thank you for explaining how to solve Leopard slow internet / slow DNS issue by bypassing the router for DNS queries using network preferences!

A couple of questions on bypassing the router’s DNS.
1. It appears that adding the DNS server in network preferences under one account applies to all accounts. Is this correct? (Note that if you change the IPv6 setting in Firefox that must still be done for each user account).
2. If I wanted to I could still use the DNS provided by my ISP by specifying that server instead of or in addition to the OpenDNS servers, correct?

BTW, I promoted this search result in Google because it was such a helpful support article. I will also promote it at the other sites that I used when trying to solve this problem. Thanks Ben!
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Below is a description of my problem and how I solved it so that it might help others fix their slow internet / DNS issues / cannot connect to server in OS X Leopard.
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I had been having trouble connecting to websites periodically ever since I got an aluminum MacBook. The problem was occurring in Firefox, Safari, and even non-browser programs. I had the hardest time figuring out the cause. I noticed Firefox would display “looking up …” or “waiting for server …” in the status bar for several seconds. Once the site was found content loaded very quickly. But some sites would refuse to load. Clicking refresh would not get the site to load no matter how many times I tried. Only waiting a long time and trying again would work.

On Apple’s support site I saw many people complaining about poor internet speeds and they believed it was due to a bug with the wireless card on the late 2008 aluminum macbooks. Well I thought this might be the problem too, but there seemed to be no solution. Then I tested with a mid 2008 white macbook and found there was still the same problem. So I figured the problem was elsewhere.

Well I eventually found some information describing the cause of the problem on the JungleDisk blog http://blog.jungledisk.com/2007/10/31/leopard-dns-issues-and-work-around/ . The solution I got from that site and others was to flush the DNS cache of OS X. However, this does not prevent the problem from occurring. It only made the computer actually retry to contact the server. I was still having slow connections and still getting “failed to connect to server” or “server not found”.

Then I tried to use a different DNS server. I changed my router settings to use OpenDNS instead of my ISP’s DNS servers. This still did not resolve the problem. I also tried updating my router’s firmware. However, there is no newer firmware and no IPv6 support. It looks like my router will never be compatible with IPv6. I was planning to get a new router anyways. Now when I upgrade I will look for IPv6 support!

Having found the wonderful article here, I learned that it was possible to bypass the DNS server/forwarder inside my router. Then I could choose a DNS server that supports the SRV requests that Leopard uses. This way the broken link in the chain is eliminated.

So I followed your instructions to add the OpenDNS servers to OS X network configuration (not my router’s config). This bypasses the DNS in the router and uses the DNS server directly. This solved the problem!

For good measure, I also turned off IPv6 support in Firefox.

I now have much faster internet again! Thank you so much for this help. Many other sites explained the problem well enough, but only this site gave a working solution! Thank you for explaining how to solve Leopard slow internet / slow DNS issue by bypassing the router for DNS queries using network preferences!

Jamaica

I followed along and got to the terminal part but for some reason it wouldn’t accept my password, tried a few times with no luck. So I went ahead and hit Apply and it seemed to work but then I lost the connection. So I went back to Automatic and it was connected and I noticed I had a new IP address. So far it seems to be faster than it was.

What I don’t understand is how did I get a new IP address. My understanding was that it can’t be changed.

As long as it works I’m happy.

Thanks again.

The reason OpenDNS servers (simply added to your current Network location’s DNS servers) break your Mac’s ability to talk to local services, is because OpenDNS will always return a location record for any request. This is how they make their money: by returning search results for non-existent domains. Even ISPs have started this practice, so it’s becoming ever more rare to avoid this problem.

I’m wondering if you followed a good set of “google instructions” or a bad set.

Have you tried these instructions on using specific dns servers for specific domains?

I did add the domain to /etc/resolver like I saw how to do somewhere else on google. This fixed the ‘not being able to locally connect to stuff’ problem, but the internet on these Mac’s are still terribly slow. Those DNS entries I put in for opendns, do work on my own MacBook pro, so it’s not them. And, they are on the bottom of the dns reverse lookup (meaning they should be used first).

Anyone have any suggestions?

I recently ran into some Apple AirPort wireless Internet problems myself with Leopard 10.5.2. In particular the wireless connection strength would momentarily drop, Leopard would search for another stronger base station without success, but in the meantime, my current connection to my original base station is lost, never to return.

The fix was rather simple: delete the com.apple.airport.preferences.plist file and let Leopard create a new one. Get the full instructions here.