Robtex

Up: 216.136.168.0/21
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Down left: 216.136.172.0/23
Down right: 216.136.174.0/23

IP	Type	Hostname
216.136.172.0	PTR	unknown-216-136-172-x.yahoo.com
216.136.172.116	A+PTR	mx1m.mail.yahoo.com
216.136.172.117	A+PTR	mx1m.mail.yahoo.com
216.136.172.118	A+PTR	mx1m.mail.yahoo.com
216.136.172.119	A+PTR	mx1m.mail.yahoo.com
216.136.172.130	A	nfs14101-a.mail.yahoo.com
216.136.172.152	A+PTR	nfs101-a.bizmail.yahoo.com
216.136.172.209	A	web13403.mail.yahoo.com
216.136.173.0	A+PTR	nfs102-a.bizmail.yahoo.com
216.136.173.144	A	web13405.mail.yahoo.com
216.136.173.172	A	web13406.mail.yahoo.com
216.136.173.211	A	web21310.mail.yahoo.com
216.136.174.8	A	ysync.yahoo.com
216.136.174.24	PTR	relay.mail.yahoo.com
216.136.174.35	PTR	unknown-216-136-174-x.yahoo.com
216.136.174.43	A+PTR	web104.biz.mail.yahoo.com
216.136.174.44	A	web20513.mail.yahoo.com
216.136.174.62	PTR	unknown-216-136-174-x.yahoo.com
216.136.174.77	PTR	unknown-216-136-174-x.yahoo.com
216.136.174.116	PTR	nfslimbo1.mail.yahoo.com
216.136.174.118	A	nfs11301-a.mail.yahoo.com
216.136.174.128	A	web14401.mail.yahoo.com
216.136.174.136	PTR	unknown-216-136-174-x.yahoo.com
216.136.174.146	PTR	unknown-216-136-174-x.yahoo.com
216.136.174.190	PTR	unknown-216-136-174-x.yahoo.com
216.136.174.208	A+PTR	web106.biz.mail.yahoo.com
216.136.174.209	A+PTR	web107.biz.mail.yahoo.com
216.136.174.212	A+PTR	web21313.mail.yahoo.com
216.136.174.213	PTR	web21314.mail.yahoo.com
216.136.174.227	PTR	unknown-216-136-174-x.yahoo.com
216.136.174.255	PTR	unknown-216-136-174-x.yahoo.com
216.136.175.1	A	ysync.yahoo.com
216.136.175.2	A	ysync.yahoo.com
216.136.175.62	PTR	unknown-216-136-175-x.yahoo.com
216.136.175.72	A	mta623.mail.yahoo.com
216.136.175.97	PTR	unknown-216-136-175-x.yahoo.com
216.136.175.128	A+PTR	mta629.mail.yahoo.com
216.136.175.146	A+PTR	cache1.oa.yahoo.com
216.136.175.184	A	db4.jake.yahoo.com
216.136.175.186	A	e1a.travel.yahoo.com
216.136.175.199	A+PTR	images.yimg.com
216.136.175.200	A+PTR	images.yimg.com
216.136.175.201	A+PTR	nfs-mirror1-store.yahoo.com
216.136.175.255	PTR	unknown-216-136-175-x.yahoo.com