Last week, I was trying to access a web page on my daughter’s school web site, www.austinisd.org, and the page would not come up. At first, I thought it might be a server load issue, since everyone is gearing up to go back to school.

To investigate, I opened a shell window and tried to ping the site with command, ping www.austinisd.org. Usually, when you ping a site, such as ping google.com the command will return with the web site’s IP address.

$ ping www.google.com
PING www.google.com (74.125.227.145): 56 data bytes
64 bytes from 74.125.227.145: icmp_seq=0 ttl=59 time=9.359 ms
64 bytes from 74.125.227.145: icmp_seq=1 ttl=59 time=9.313 ms
64 bytes from 74.125.227.145: icmp_seq=2 ttl=59 time=9.307 ms
64 bytes from 74.125.227.145: icmp_seq=3 ttl=59 time=9.090 ms

With those results I knew a few things. The domain www.google.com would resolve to the IP address 74.125.227.145 and this server was responding back to my ping requests.

When I tried to ping the school’s web server, I never did get an IP address from the DNS server. Instead I received the following error message.

$ ping www.austinisd.org
ping: cannot resolve www.austinisd.org: Unknown host

My solution was to change my DNS resolver setting on my Mac to point to a different DNS server. Google runs a DNS resolver at 8.8.8.8 and I added this to my settings and Bam! I can now connect to www.austinisd.org.

Mac DNS Settings Screenshot

$ ping www.austinisd.org
PING austinisd.org (206.77.0.250): 56 data bytes
64 bytes from 206.77.0.250: icmp_seq=0 ttl=54 time=37.234 ms
64 bytes from 206.77.0.250: icmp_seq=1 ttl=54 time=35.116 ms
64 bytes from 206.77.0.250: icmp_seq=2 ttl=54 time=35.513 ms

– Chris