I am Unable to Resolve Anything?

There are a number of problems that can cause your computer to be unable to resolve anything:

The DNS settings in your computer could be configured
The network settings in your computer could be configured
Your DNS servers could all be broken
The network between your computer and your DNS servers could be down
A firewall could be blocking your DNS requests, or the DNS replies

Troubleshooting Being Unable to Resolve Anything

The first thing to do when troubleshooting the problem of being unable to resolve anything is to determine if IP networking, other than DNS, is working properly.

To test networking, ping an IP address across the Internet that you recognize and that you are certain works normally.


C:\>ping 199.196.144.95



Pinging 199.196.144.95 with 32 bytes of data:



Reply from 199.196.144.95: bytes=32 time=41ms TTL=243

Reply from 199.196.144.95: bytes=32 time=42ms TTL=243

Reply from 199.196.144.95: bytes=32 time=36ms TTL=243

Reply from 199.196.144.95: bytes=32 time=41ms TTL=243



Ping statistics for 199.196.144.95:

    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

Approximate round trip times in milli-seconds:

    Minimum = 36ms, Maximum = 42ms, Average = 40ms

If this works, then at least some networking is working for you and you have a DNS problem. If this fails, then your network is not working.

Let's try to do a DNS name resolution and see if it works: C:\>nslookup Default Server: ns2.attbi.com Address: 216.148.227.68 > www.tech-faq.com Server: ns2.attbi.com Address: 216.148.227.68 Non-authoritative answer: Name: www.tech-faq.com Address: 66.37.153.76

If this works, then you can at least resolve some things.

If this fails, then you might try to use a different DNS server. In this example, we borrow DNS service from GTE Internet:


C:\>nslookup

Default Server:  ns2.attbi.com

Address:  216.148.227.68



> server 4.2.2.2

Default Server:  vnsc-bak.sys.gtei.net

Address: 4.2.2.2



> www.tech-faq.com

Server:  vnsc-bak.sys.gtei.net

Address: 4.2.2.2



Non-authoritative answer:

Name:    www.tech-faq.com

Address:  66.37.153.76

If this works, then your network is working and it is also likely that no firewall is blocking DNS traffic.

Your DNS servers could be broken, the network to your DNS servers could be broken, or your computer could be configured for the wrong DNS servers.

The next step is to manually check the DNS server settings on your computer:

Checking DNS Server Settings under Microsoft Windows

Click the <Start> button
Click <Control Panel>
If you are not already in Category View, click <Switch to Category View>
Doubleclick <Network Connections>
Doubleclick the network connection which connects your computer to the Internet
Click <Properties>
Doubleclick Internet Protocol (TCP/IP)
Compare the values set for Obtain DNS server address automatically, Preferred DNS server and Alternate DNS server with the correct values for your network
Click <OK>
Click <OK>

Checking DNS Server Settings under Unix

Under Unix, you configure you DNS servers by editing the file /etc/resolve.conf:
# cat /etc/resolv.conf domain tech-faq.com nameserver 208.25.104.7 nameserver 205.161.148.7