Robtex

Up: 72.30.224.0/21
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Down left: 72.30.224.0/23
Down right: 72.30.226.0/23

IP	Type	Hostname
72.30.224.71	PTR	ha7.ge-11-18.bas-1-con.ac2.yahoo.com
72.30.224.136	PTR	ha8.ge-11-19.bas-1-con.ac2.yahoo.com
72.30.224.164	PTR	unknown-72-30-224-x.yahoo.com
72.30.225.3	A	ha3.ge-12-5.bas-1-con.ac2.yahoo.com
72.30.226.8	A	ha8.ge-12-1.bas-1-con.ac2.yahoo.com
72.30.226.9	A	ge-12-1.bas1-1-con.ac2.yahoo.com
72.30.226.16	PTR	ge-12-1.bas8-1-con.ac2.yahoo.com
72.30.226.63	PTR	unknown-72-30-226-x.yahoo.com
72.30.226.74	A+PTR	ge-13-0.bas2-1-con.ac2.yahoo.com
72.30.227.4	A+PTR	ha4.ge-13-34.bas-1-con.ac2.yahoo.com