This works for me on Centos 5.6. It may assist newcomers to the Linux world of Centos.
whois 51.51.51.51
produces a normal and conventional display of data.
However since ARIN, the North American registrar of IP addresses, "modernised" its WHOIS processing, a query to
whois 64.64.64.64
will produce a one line summary of possible matches, which always includes ARIN, but omits the details we used to receive before ARIN implemented its much criticised "improved" service.
A one line script solves it for me (but only for ARIN network entries).
#!/bin/bash whois -h whois.arin.net n + $1
I call my script .arin
.arin 64.64.64.64
produces a normal output.
Paul.