How OpenDNS solved my really annoying DNS problem
About 3 weeks ago I started getting the "Page Cannot be Displayed" error message on my machine when using my home network. It would happen occasionally at first, maybe 1 in 20 sites. When the error occurred, I'd hit refresh - that would solve it in 1 in 5. If that didn't work, I'd try the site with Firefox where the error repeated in around 1 in 2. In an hour or so, a site that didn't work previously would and a site that did work previously wouldn't. Annoying.
I couldn't replicate this behaviour on my company network, so I was sure it was either my local machine or my router. I tried the usual things to try and clear up the problem (ipconfig /release, /renew, /flushdns), enable/disable network adapters, remove temp files in browser, reboot the router, reset the router, etcetera, etcetera. I had some hope as the ipconfig /flushdns would solve the problem in maybe 1 in 3, but then the site would get funky again in a few minutes. Annoying.
Then my wife complained that she was getting the same problem on her machine, for the past few days or so. So I boiled it down to either my router going weird on me or my ISPs dns server doing something funky. I called the ISP and they hadn't heard of any similar issue reported by other customers. I tried to replicate the problem while on the phone with the ISP (I did, eventually, after everything began working perfectly the instant I had a support engineer on the line...) but they didn't have an answer - as far as they were concerned everything was cool at their end. Annoying.
I contacted my router's manufacturer (D-LINQ). They suggested changing the dns settings on the adapters manually to 4.2.2.1 and 4.2.2.2. This worked a little better for an evening (e.g. 1 in 20 would fail instead of 1 in 10 by this point), but it didn't solve the issue, not even close. In fact, things started getting worse the next day. I was convinced it was a router issue so I popped to Fry's and bought another (DLINQ again - I'm loving their routers btw). I got home, set up the new router and yet the issue was still there. Annoying.
Believing it wasn't a problem with the machines, and believing it wasn't a problem with the ISP's dns server (well, that's what they told me), and believing it wasn't a problem with (either of) my router(s) or its settings, I believed I was at a loss and, yes, quite annoyed.
While going mad looking for other solutions online ('cause I wasn't connecting to the sites, at this time around 1 in 2...), I stumbled across OpenDNS.com. I read the FAQ (especially the privacy related stuff), read about the various other benefits and gave it a go. I followed the instructions to set my router to use the OpenDNS service and, magically, everything worked. I've been using the service (free) for a week now and I've not had the slightest problem on any machines on my network. Instantly un-annoyed.
So I did find a work-around...but I didn't find the root cause...and I'm curious. I should get back to the ISP and let them know how I fixed it - presumably the fact that the OpenDNS solution worked for me points to a problem with their dns server? We'll see.