Robtex

Up: 216.39.54.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 216.39.55.0/25
Down right: 216.39.55.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
216.39.55.1	PTR	ha1.et-18-17.bas-1-cld.gq1.yahoo.com
216.39.55.3	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.4	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.11	PTR	nu1.rtu.vip.gq1.yahoo.com
216.39.55.12	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.12	A	ad.marschannels.com
216.39.55.12	A	fd-world.ngd.ysm.yahoodns.net
216.39.55.13	A+PTR	mpr2.ngd.vip.gq1.yahoo.com
216.39.55.13	A	ad.marschannels.com
216.39.55.13	A	fd-world.ngd.ysm.yahoodns.net
216.39.55.14	PTR	bap1.ngd.vip.gq1.yahoo.com
216.39.55.15	PTR	bap2.ngd.vip.gq1.yahoo.com
216.39.55.18	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.19	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.20	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.26	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.29	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.33	PTR	entity01.cal.vip.gq1.yahoo.com
216.39.55.35	PTR	range.rm.vip.gq1.yahoo.com
216.39.55.36	PTR	holiday.cal.vip.gq1.yahoo.com
216.39.55.37	PTR	uiad1.rm.vip.gq1.yahoo.com
216.39.55.37	A	uiad-world.ngd.ysm.yahoodns.net
216.39.55.38	PTR	uiad2.rm.vip.gq1.yahoo.com
216.39.55.38	A	uiad-world.ngd.ysm.yahoodns.net
216.39.55.40	PTR	kafka-prod.ysm.vip.gq1.yahoo.com
216.39.55.41	PTR	repl-proxy-prod.ysm.vip.gq1.yahoo.com
216.39.55.43	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.44	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.46	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.48	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.55	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.59	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.60	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.61	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.62	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.63	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.66	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.68	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.70	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.71	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.76	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.80	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.81	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.83	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.88	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.90	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.91	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.92	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.93	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.96	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.97	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.102	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.107	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.111	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.114	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.115	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.119	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.122	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.126	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.129	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.130	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.132	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.136	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.145	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.149	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.150	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.153	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.161	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.165	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.167	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.169	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.172	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.175	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.176	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.178	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.179	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.183	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.184	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.192	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.193	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.197	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.202	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.204	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.209	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.210	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.215	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.217	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.218	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.223	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.226	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.228	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.229	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.235	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.239	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.240	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.241	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.243	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.245	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.250	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.251	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.252	PTR	unknown-216-39-55-x.yahoo.com
216.39.55.253	PTR	unknown-216-39-55-x.yahoo.com