Robtex

Up: 66.196.80.0/21
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Down left: 66.196.84.0/23
Down right: 66.196.86.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
66.196.84.0	PTR	unknown-66-196-84-x.yahoo.com
66.196.84.25	PTR	unknown-66-196-84-x.yahoo.com
66.196.84.168	PTR	unknown-66-196-84-x.yahoo.com
66.196.84.168	A	www.recoverguide.com
66.196.84.168	A	paradisegoods.com
66.196.85.1	PTR	unknown-66-196-85-x.yahoo.com
66.196.85.29	PTR	unknown-66-196-85-x.yahoo.com
66.196.85.29	A	bix.ie
66.196.85.48	PTR	unknown-66-196-85-x.yahoo.com
66.196.85.51	PTR	unknown-66-196-85-x.yahoo.com
66.196.85.57	PTR	unknown-66-196-85-x.yahoo.com
66.196.85.71	PTR	su646.usne1r.dht.bf1.yahoo.com
66.196.85.99	PTR	su031.usne2.dht.bf1.yahoo.com
66.196.85.127	PTR	unknown-66-196-85-x.yahoo.com
66.196.85.254	PTR	unknown-66-196-85-x.yahoo.com
66.196.86.24	PTR	unknown-66-196-86-x.yahoo.com
66.196.86.34	A+PTR	fe06.yhs.search.bf1.yahoo.com
66.196.86.37	A	fe09.yhs.search.bf1.yahoo.com
66.196.86.40	A+PTR	fe12.yhs.search.bf1.yahoo.com
66.196.86.46	PTR	fe18.yhs.search.bf1.yahoo.com
66.196.86.47	PTR	unknown.yahoo.com
66.196.86.47	A	fe19.yhs.search.bf1.yahoo.com
66.196.86.53	A+PTR	fe25.yhs.search.bf1.yahoo.com
66.196.86.70	PTR	ymsthr-13.ops.bf1.yahoo.com
66.196.86.81	PTR	rtr1.l7.search.vip.bf1.yahoo.com
66.196.86.81	A	dk.altavista.com
66.196.86.81	A	prod7.l7.search.ysta1.b.yahoo.com
66.196.86.84	PTR	unknown-66-196-86-x.yahoo.com
66.196.86.91	A+PTR	ssol.qa3.uni.vip.bf1.yahoo.com
66.196.86.92	A	pprd3-node100-lh1.manhattan.bf1.yahoo.com
66.196.86.105	A	pprd3-node107-lh2.manhattan.bf1.yahoo.com
66.196.86.106	A	pprd3-node107-lh3.manhattan.bf1.yahoo.com
66.196.86.116	A	ymsuibot-01.ops.vip.bf1.yahoo.com
66.196.86.131	A+PTR	beacon1.bkln.bf1.yahoo.com
66.196.86.133	PTR	unknown.yahoo.com
66.196.86.133	A	lib.store.yahoodns.net
66.196.86.139	A	splunk-spare9.cocktails.bf1.yahoo.com
66.196.86.143	A	ygnfs-02.grp.bf1.yahoo.com
66.196.86.156	PTR	unknown.yahoo.com
66.196.86.156	A	engine22.v2.yql.bf1.yahoo.com
66.196.86.208	A	supervisor51.mqengine.media.bf1.yahoo.com
66.196.86.209	A	supervisor52.mqengine.media.bf1.yahoo.com
66.196.86.211	A	supervisor54.mqengine.media.bf1.yahoo.com
66.196.86.214	A	supervisor57.mqengine.media.bf1.yahoo.com
66.196.86.246	A	fe57.yhs.search.bf1.yahoo.com
66.196.86.247	A	fe58.yhs.search.bf1.yahoo.com
66.196.86.252	A	fe62.yhs.search.bf1.yahoo.com
66.196.87.11	PTR	fe004.syc.search.bf1.yahoo.com
66.196.87.111	PTR	unknown-66-196-87-x.yahoo.com
66.196.87.111	A	syndicate1.nads.g04.yahoodns.net
66.196.87.111	A	syndication.streamads.yahoo.com
66.196.87.126	PTR	gw03.llog.search.bf1.yahoo.com
66.196.87.127	A+PTR	gw04.llog.search.bf1.yahoo.com
66.196.87.129	PTR	unknown-66-196-87-x.yahoo.com
66.196.87.129	A	gw06.llog.search.bf1.yahoo.com
66.196.87.131	PTR	unknown-66-196-87-x.yahoo.com
66.196.87.131	A	gw08.llog.search.bf1.yahoo.com