Okay I finally fixed this issue, and boy was it simple. Turns out Comcast didn't have my second modem registered and thus was not getting the proper configuration. So after some talking they added it, and viola the DNS problem is gone.
Ahh, nice work. I did have a hunch it was a problem at Comcast's end. Well done. Make sure to mark this thread as solved too.
Okay its happening again now, I tried power cycling but that didn't fix it, I checked my Xfinity Account and it shows the modem on my account so do I call them again or something?
Okay called again and they fixed it, but now they are saying I may still get this issues since my two modems the SB6141 are at "end of life" so does anyone know if this is true, cause I know Comcast likes to say things that aren't always true.
Sounds like they are partially right according to this article: The Best Cable Modem so it sounds like its successor (SB6183) is more compatible with a multi modem network, but in saying this the SB6141 is probably ideal for those who need just one modem. It sounds like it is defiantly a higher paid option but you can probably get a guarantee from Comcast if you upgrade...
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