DNS issues: Finding a DNS server

As we've covered the widespread issue with Safari (and other browsers) not being able to connect on the first try due to DNS issues, we've noted that one of the most successful solutions has been to manually enter your ISP's DNS server address(es) in the DNS Servers field of the TCP/IP tab of your Internet connection port in Network preferences. Unfortunately, some ISPs don't seem to be as cooperative as they could be. In addition to the methods previously covered, several options exist for locating DNS server addresses:

As noted by Randy Smith, you can use the unix DIG command in the terminal with the appropriate virtual server name for your ISP. Comcast users would use:

• dig ns attbi.com

"Look for entries in the answer section with NS by them these are the DNS servers, The addresses of servers are in the additional section

Another reader adds:

"The easiest and most sure-fire method for determining DHCP-supplied DNS information is to use the Terminal:

• $ cat /etc/resolv.conf

"This will report the Search Domains (domain) and DNS Servers (nameserver). Any time that you click 'Apply Changes' in the Network Preferences it will recreate this file (so don't bother editing it by hand). If you manually enter one or more DNS Servers (via System Preferences: Network: TCP/IP) it will prepend those DNS Servers to the nameserver list (i.e., giving them priority over the DHCP-supplied nameservers).

"Note: if you have a wired/wireless router it may or may not pass the DNS servers through (i.e., if your nameserver address is also your gateway/router address, then it's not passing it through and you'll have to log into your router directly to see what nameservers it is using)."

Meanwhile, Alex Kac notes another solution for those using a Mac OS X box as a DNS server:

"I use OS X Server as my DNS server for our network and out of the box it runs BIND 9.22. I installed BIND 9.3 in /usr/local/bin and then added a config option to named.conf to better handle 512 byte UDP packets and changed the startup option to run bind as /usr/local/bin/named ?4 ?c .....with my config file. Restarted BIND and now everything works very well."

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