Rogue DNS Entry Causing Problems

Question

I'm running Mac OS X (wired connection) and on a really crappy ISP. Because of this I've set my DNS servers to use OpenDNS, which is generally much more responsive. However, for some reason 192.168.1.1 is at the top of my DNS search order (confirmed via /etc/resolv.conf and nslookup). The problem is that it's not listed anywhere in my network configuration. It might be coming from DHCP, but I've read that if it is it should be last in the list. How do I remove this altogether, or at the very least force Mac OS X to always try it last?

Additional Information:

Very strange. When I go into System Preferences, only the OpenDNS servers are listed. I've checked every adapter listed, whether they are enabled or not (including Bluetooth, Firewire, etc.). When I run networksetup -getdnsservers Ethernet it only returns the OpenDNS servers.

However if I cat /etc/resolv.conf I get

nameserver 192.168.1.1
nameserver 208.67.222.222
nameserver 208.67.220.220

And nslookup gives me:

> server
Default server: 192.168.1.1
Address: 192.168.1.1#53
Default server: 208.67.222.222
Address: 208.67.222.222#53
Default server: 208.67.220.220
Address: 208.67.220.220#53

When I look something up in nslookup it sometimes responds with 192.168.1.1 and sometimes with an OpenDNS server. And sometimes it times out completely due to my aforementioned crappy ISP.

Answer 1

How did you set your DNS to use OpenDNS?

In the Network preference pane in System Preferences, if you click Advanced... on your Airport and go to the DNS tab: What is the order that appears there? Is 192.168.1.1 in grey or black?

If the IP address is black it's been manually entered, if it's grey it came via DHCP. You can also drag and drop entries to change the order as necessary. /etc/resolv.conf is auto generated from these settings so changing /etc/resolv.conf won't stick. If you want to set the DNS servers and manage them from the command line, check out networksetup. (eg. networksetup -getalldnsservers AirPort)