/etc/resolv.conf domain and search

在/etc/resolv.conf 配置文件：domain 和search作用是一样的

domain linpro.no
search linpro.no uio.no ifi.uio.no

domain function:

Had I typed telnet math.uio.no. with the trailing dot, the resolver would have known it was an FQDN and would have looked up math.uio.no at once, without trying to append the specified domain first. Not all applications are tolerant of the trailing dot, though, so it can't always be specified.

search function:

When ssh gram is executed, the resolver first looks for gram.linpro.no, which does not exist; then gram.uio.no, which does not exist, either; and finally gram.ifi.uio.no, which will succeed because it does exist