Robtex

Up: 72.30.48.0/20
Can't show all results, try to descend to a more specific CIDR
Down left: 72.30.56.0/22
Down right: 72.30.60.0/22

IP	Type	Hostname
72.30.57.16	PTR	unknown-72-30-57-x.yahoo.com
72.30.57.208	PTR	unknown-72-30-57-x.yahoo.com
72.30.57.209	PTR	unknown-72-30-57-x.yahoo.com
72.30.60.2	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.2	A	ha2.po-18.bas-d.sk1.yahoo.com
72.30.60.3	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.9	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.10	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.11	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.16	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.24	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.26	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.35	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.42	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.48	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.56	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.65	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.66	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.73	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.77	A	ui-26.roles.bf1.yahoo.com
72.30.60.83	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.88	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.91	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.96	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.97	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.107	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.112	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.122	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.139	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.144	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.146	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.160	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.162	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.177	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.179	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.185	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.192	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.194	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.201	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.202	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.210	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.216	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.216	A	ui-05.roles.bf1.yahoo.com
72.30.60.217	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.225	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.227	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.232	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.234	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.240	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.241	PTR	unknown-72-30-60-x.yahoo.com
72.30.60.249	PTR	unknown-72-30-60-x.yahoo.com
72.30.62.85	A	pud5058.udb.bf1.yahoo.com
72.30.63.129	PTR	ha1.po-32.bas-d.sk1.yahoo.com
72.30.63.206	A	idx20.splunk.udb.bf1.yahoo.com