I'm stumped. We have a solaris network that uses both DNS and NIS. For the moment they both have the same domain name (aaa.bbb.com). I need to change the default DNS domain name. I edited resolv.conf and changed it to ccc.ddd.com. I then tested resolution of a host in the original domain. My test : nslookup host1.aaa.bbb.com. As I expected nslookup failed to resolve the name. I then tried ping host1 and expected name resolution failure but was surprised to see that host1 was resolved and the ip address was pinged. Got the same result with telnet host1. Success when I expected failure. I see that these 2 DNS client applications do not use the domain name in resolv.conf as their default. I cleared nscd cache and stopped nscd. The info isn't / wasn't cached. I checked /etc/hosts. Host1 isn't defined there. I now suspect /etc/defaultdomain which still has aaa.bbb.com in it. I understand that NIS is using this file for its default domain information. How can I force the DNS client applications to look elsewhere for their default domain name?