Robtex

Up: 8.21.152.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 8.21.152.0/23
Down right: 8.21.154.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
8.21.152.32	A	mx-nono.blueone.net
8.21.152.34	A+PTR	ns1.blueone.net
8.21.152.34	A	ns3.blueone.net
8.21.152.34	A	main.ure.net
8.21.152.35	PTR	modusmail.blueone.net
8.21.152.36	A+PTR	mail.blueone.net
8.21.152.36	A	mail.bell-whitley.org
8.21.152.36	A	mail.dupreecatering.com
8.21.152.37	PTR	mail.ure.net
8.21.152.39	PTR	www.blueone.net
8.21.152.40	A	secure.blueone.net
8.21.152.40	A	webmail.blueone.net
8.21.152.41	A+PTR	support.blueone.net
8.21.152.43	A+PTR	ns2.blueone.net
8.21.152.44	PTR	webserver.blueone.net
8.21.152.44	A	businessprintingamerica.com
8.21.152.44	A	sideshowart.com
8.21.152.45	PTR	norstarsource.com
8.21.152.47	PTR	ure.net
8.21.152.49	PTR	frontpage.blueone.net
8.21.152.49	A	newcastle.blueone.net
8.21.152.49	A	blueone.biz
8.21.152.55	A	voipparty.com
8.21.152.55	A	voiplounge.com
8.21.152.55	A	www.voiplounge.com
8.21.152.57	A+PTR	mx.blueone.net
8.21.152.57	A	mx-no.blueone.net
8.21.152.61	A	guinness.blueone.net
8.21.152.98	A	pbx.blueone.net
8.21.153.18	A	riseconsulting.com
8.21.153.18	A	risesystems.com
8.21.153.18	A	eardleyfactor.com
8.21.153.26	A+PTR	baconhouse.sackheads.org
8.21.153.26	A	phl.nameserver.net
8.21.153.26	A	mx.sackheads.org
8.21.153.38	A	mail.jenkinsbailey.com
8.21.153.38	A	mail.mediatelex.com
8.21.153.38	A	mail.jprlex.com
8.21.153.50	PTR	mail.lexcomsys.com
8.21.153.50	A	mail.bennett-energy.com
8.21.153.50	A	mail.taylordental.net
8.21.153.129	A+PTR	vpn.blueone.net
8.21.153.131	A	rose.csplan.com
8.21.153.133	A	pbx1.kykids.org
8.21.155.34	A	ns4.blueone.net
8.21.155.43	A	a-seizure.com
8.21.155.46	A	institute193.com