This article is from the the Brief Linux FAQ (BLFAQ) Maintained by Neil Zanella nzanella@ganymede.cs.mun.ca
You should be able to get rid of this problem by adding an entry for a name server in the file /etc/resolv.conf . If you have more than one name server then you should put your primary dns first as nameserver entries get read from top to bottom. The 'search' or 'domain' line should have your isp's domain name. Your /etc/resolv.conf should look something like:
search virtual-impact.com domain virtual-impact.com nameserver 205.162.94.51 nameserver 205.162.88.33 nameserver 134.153.2.90
 
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