Robtex

Up: 72.30.64.0/19
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Down left: 72.30.64.0/21
Down right: 72.30.72.0/21

IP	Type	Hostname
72.30.64.0	PTR	ge-0-1-0.msr1.ac2.yahoo.com
72.30.64.17	A+PTR	ge-0-0-2.clr1.ac2.yahoo.com
72.30.64.33	PTR	ge-0-0-2.clr2.ac2.yahoo.com
72.30.64.176	PTR	lo1.bas-d.ac2.yahoo.com
72.30.64.176	A	bas-d.ac2.yahoo.com
72.30.64.177	A	bas-c.ac2.yahoo.com
72.30.64.180	A	lo0.bas-c1.ac2.yahoo.com
72.30.64.186	A	bas-a1.ac2.yahoo.com
72.30.64.232	A	yw1.ops.ac2.yahoo.com
72.30.67.145	PTR	unknown-72-30-67-x.yahoo.com
72.30.70.227	PTR	unknown-72-30-70-x.yahoo.com
72.30.72.35	PTR	unknown-72-30-72-x.yahoo.com
72.30.75.98	PTR	unknown-72-30-75-x.yahoo.com