DNS Issues after Updating to Mountain Lion I've updated to Mountain Lion, and I'm having some DNS problems. I always PPTP/L2TP VPN connections on my macbook. Recently after a while of working with Mountain Lion, VPN stops sending and receiving data and I have to disconnect/connect again to make it work again. I'm not having the same problem with iPad, iPhone and PC.

and without the VPN, when I try pinging 4.2.2.4 , 8.8.8.8 and other DNSs and all I get is timeouts! But the ping works fine on my other devices. I also tried setting the DNS to Google and OpenDNS DNSs (8.8.4.4, 4.2.2.4, 8.8.8.8, ...) but it still didn't help. I also tried emptying DNS cache and other solutions. but nothing.

I'm guessing that these two problems are tied together.
Any solutions?

Thanks.
change the primary DNS to your local gateway address, like 192.168.1.1 or 192.168.0.10...
I have the same problem in PC, try it, It may be useful ;)