Robtex

Up: 66.163.160.0/20
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Down left: 66.163.168.0/22
Down right: 66.163.172.0/22
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
66.163.168.0	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.8	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.9	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.10	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.11	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.14	A	o2.ycpi.ne1.yahoo.com
66.163.168.14	A	r-t-ccx8bgq0yhreport.wc.yahoodns.net
66.163.168.15	A	o1.ycpi.ne1.yahoo.com
66.163.168.35	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.41	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.42	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.48	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.49	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.50	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.51	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.56	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.57	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.58	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.59	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.82	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.83	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.88	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.89	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.92	A	x1.ycpi.ne1.yahoo.net
66.163.168.99	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.100	A	cms1.buzz.vip.sp1.yahoo.com
66.163.168.112	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.113	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.114	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.177	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.178	A+PTR	n44c.bullet.mail.sp1.yahoo.com
66.163.168.194	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.195	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.209	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.210	A+PTR	fe1.rd.aunz.vip.sp1.yahoo.com
66.163.168.225	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.225	A	fe1.bff.search.vip.sp1.yahoo.com
66.163.168.227	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.240	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.241	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.242	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.243	PTR	unknown-66-163-168-x.yahoo.com
66.163.168.249	PTR	unknown-66-163-168-x.yahoo.com
66.163.169.1	A	nfs80101-a.mail.yahoo.com
66.163.169.29	A	nfs20401-b.mail.yahoo.com
66.163.169.42	A+PTR	ns2-new.yahoo.com
66.163.169.43	A+PTR	report.be.travel.vip.sp1.yahoo.com
66.163.169.51	A	web21512.mail.yahoo.com
66.163.169.89	A	web20401.mail.yahoo.com
66.163.169.90	A+PTR	web20402.mail.yahoo.com
66.163.169.91	A	web20403.mail.yahoo.com
66.163.169.93	A	web20405.mail.yahoo.com
66.163.169.96	A	web20408.mail.yahoo.com
66.163.169.100	A	hjdb02.stage.hj.sp1.yahoo.com
66.163.169.102	A	nfs20401-c.mail.yahoo.com
66.163.169.105	A	buzz.vip.sp1.yahoo.com
66.163.169.142	A	mlogin01.stage.hj.sp1.yahoo.com
66.163.169.156	A	n42d.bullet.mail.sp1.yahoo.com
66.163.169.157	A	n43d.bullet.mail.sp1.yahoo.com
66.163.169.169	A+PTR	ups-free10.npn.sp1.yahoo.com
66.163.169.170	A+PTR	ns20.yahoo.com
66.163.169.170	A	ns2.san.yahoo.com
66.163.169.170	A	ns2.dca.yahoo.com
66.163.169.186	PTR	unknown-66-163-169-x.yahoo.com
66.163.169.186	A	tensuntek.com
66.163.169.186	A	yahoo.eddieonofre.com
66.163.169.240	PTR	yts1.bix.vip.sp1.yahoo.com
66.163.169.242	A	mx.ypsearch.yahoo.com
66.163.169.243	A	mx.ypsearch.yahoo.com
66.163.170.8	A+PTR	si-c3.vl127.sp1.yahoo.com
66.163.170.27	A	web20412.mail.yahoo.com
66.163.170.28	A	web20413.mail.yahoo.com
66.163.170.36	A	web80113.mail.yahoo.com
66.163.170.37	A	web80114.mail.yahoo.com
66.163.170.43	PTR	unknown-66-163-170-x.yahoo.com
66.163.170.56	PTR	unknown-66-163-170-x.yahoo.com
66.163.170.68	A	be.bff.search.vip.sp1.yahoo.com
66.163.170.70	A	nfs80701.mail.yahoo.com
66.163.170.72	PTR	unknown-66-163-170-x.yahoo.com
66.163.170.74	A+PTR	mdbfed.video.search.vip.sp1.yahoo.com
66.163.170.89	A	web80724.mail.yahoo.com
66.163.170.91	A	web80726.mail.yahoo.com
66.163.170.93	A	web80728.mail.yahoo.com
66.163.170.107	A	mix80802.mail.yahoo.com
66.163.170.110	A	web80731.mail.yahoo.com
66.163.170.115	A	web80824.mail.yahoo.com
66.163.170.118	A	web80827.mail.yahoo.com
66.163.170.139	PTR	unknown-66-163-170-x.yahoo.com
66.163.170.211	A	web21412.mail.yahoo.com
66.163.171.33	PTR	unknown-66-163-171-x.yahoo.com
66.163.171.98	PTR	unknown-66-163-171-x.yahoo.com
66.163.171.128	A	mail.enpsolutions.org
66.163.171.147	PTR	unknown-66-163-171-x.yahoo.com
66.163.171.162	A	qr.vas.vip.sp1.yahoo.com
66.163.171.168	PTR	pclick1.data.vip.sp1.yahoo.com
66.163.171.202	PTR	unknown-66-163-171-x.yahoo.com
66.163.171.210	PTR	unknown-66-163-171-x.yahoo.com
66.163.171.224	A	qr.buzz.news.search.vip.sp1.yahoo.com
66.163.171.226	PTR	nws1.maps.vip.sp1.yahoo.com
66.163.171.226	A	gws2.maps.yahoo.com
66.163.171.252	A	ispbeta-vm1.member.sp1.yahoo.com
66.163.172.2	A	ha2.vl-232.bas-b.sp1.yahoo.com
66.163.172.33	A	si-b2.vl232.sp1.yahoo.com
66.163.172.67	PTR	unknown-66-163-172-x.yahoo.com
66.163.172.67	A	static.vap.yahoo.net
66.163.172.234	PTR	unknown-66-163-172-x.yahoo.com
66.163.173.250	PTR	unknown-66-163-173-x.yahoo.com
66.163.174.18	PTR	unknown-66-163-174-x.yahoo.com
66.163.174.33	PTR	unknown-66-163-174-x.yahoo.com
66.163.174.40	PTR	unknown-66-163-174-x.yahoo.com
66.163.174.41	PTR	unknown-66-163-174-x.yahoo.com
66.163.174.227	PTR	unknown-66-163-174-x.yahoo.com
66.163.175.38	A	nfs7-a.cal.yahoo.com