Robtex

Up: 72.11.0.0/20
Can't show all results, try to descend to a more specific CIDR
Down left: 72.11.8.0/22
Down right: 72.11.12.0/22
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
72.11.9.59	A	mail.dmcschool.net
72.11.9.82	A+PTR	mail.remlingermfg.com
72.11.9.98	PTR	holidaycity-dev1.wls.metalink.net
72.11.10.11	A	mail2.fcfhnwo.org
72.11.10.85	A	napphil-72-11-10-85.wls.metalink.net
72.11.12.223	A	aye-72-11-12-223.wls.metalink.net
72.11.13.2	A+PTR	zixgateway01.yourstatebank.com
72.11.13.2	A	zixvpm.dcminc.com
72.11.13.3	A	mail.yourstatebank.com
72.11.13.3	A	mx1.rurban.net
72.11.13.5	PTR	mx.yourstatebank.com
72.11.13.14	A	mic.rdsidata.com
72.11.13.21	A	secureonline.yourstatebank.com
72.11.13.126	A	mail.edonfarmerscoop.com
72.11.13.154	PTR	drbob.net
72.11.13.154	A	www.drbob.net
72.11.14.47	PTR	mail.rsnwo.org
72.11.14.105	A	mail.mvgcenter.org
72.11.14.130	A	exchange.nemcofoodequip.com
72.11.14.171	A	mail.insource-eng.com
72.11.14.173	A	insource-eng.com
72.11.15.76	PTR	mail.arsrefuse.com
72.11.15.76	PTR	mail.heartlanddisposal.com
72.11.15.76	PTR	mail.werlor.com
72.11.15.78	PTR	mail.werlor.com
72.11.15.86	A+PTR	mail.rsnwo.org
72.11.15.126	A+PTR	vet-72-11-15-126.wls.metalink.net
72.11.15.163	A+PTR	exchange.henrycountyhospital.org
72.11.15.163	A	mail.hchonline.org
72.11.15.228	A	mail.hubbardcompany.com