Robtex

Up: 165.212.0.0/17
Can't show all results, try to descend to a more specific CIDR
Down left: 165.212.0.0/19
Down right: 165.212.32.0/19
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
165.212.1.173	A+PTR	smtp.mbox.net
165.212.1.174	A	pop.mbox.net
165.212.1.177	PTR	attachments.mbox.net
165.212.1.179	PTR	imta.mbox.net
165.212.1.179	A	mbox.net
165.212.2.1	PTR	web1p.mbox.net
165.212.2.2	PTR	web2p.mbox.net
165.212.2.181	PTR	relay1p.mbox.net
165.212.3.6	PTR	spare1p.mbox.net
165.212.3.8	PTR	spare3p.mbox.net
165.212.3.11	PTR	omnip.mbox.net
165.212.3.146	PTR	ops1p.mbox.net
165.212.3.176	PTR	itop.mbox.net
165.212.4.1	PTR	web1s.mbox.net
165.212.4.161	PTR	mta1s.mbox.net
165.212.5.7	PTR	hcdvg772.mbox.net
165.212.8.1	A+PTR	cmsweb15.cms.usa.net
165.212.8.2	A	cmsweb02.cms.usa.net
165.212.8.7	A	cmsweb04.cms.usa.net
165.212.8.8	A	cmsweb08.cms.usa.net
165.212.8.100	A+PTR	cpdvg100.mx.net
165.212.8.110	A	provisioning.usa.net
165.212.8.110	A	upsprod2.eservices.usa.net
165.212.8.201	PTR	web01.cms.usa.net
165.212.8.220	A	reports.usa.net
165.212.8.221	A	www.mbox.net
165.212.8.221	A	postmaster.usa.net
165.212.8.240	A	mail.icbnd.com
165.212.9.2	PTR	twdvg002.cms.usa.net
165.212.9.3	A	uzdvg003.cms.usa.net
165.212.9.4	PTR	twdvg004.cms.usa.net
165.212.9.252	PTR	twdvg252.cms.usa.net
165.212.9.252	A	kandk.ipmail.att.net
165.212.9.252	A	imagenetix.ipmail.att.net
165.212.10.1	A+PTR	cmsmail01.cms.usa.net
165.212.10.11	A	netmail11.cms.usa.net
165.212.10.12	A	netmail12.cms.usa.net
165.212.10.13	A	cmsmail13.cms.usa.net
165.212.10.249	A+PTR	mxpooltest.postoffice.net
165.212.10.250	A	cmsbackend.postoffice.net
165.212.10.252	PTR	intlmail.postoffice.net
165.212.10.253	A+PTR	palmmx.postoffice.net
165.212.10.254	A	mxbackend.postoffice.net
165.212.11.2	A+PTR	ca22.cms.usa.net
165.212.11.120	A	pop.netaddress.com
165.212.11.125	A+PTR	smtp.postoffice.net
165.212.11.125	A	smtp.coldwellbanker.com
165.212.11.125	A	imap.commandsecurity.com
165.212.11.150	A+PTR	snd1.mx.net
165.212.11.151	A+PTR	snd2.mx.net
165.212.11.151	A	cmssender02.mx.net
165.212.12.1	PTR	cndvg001.usa.net
165.212.12.1	A	dnspri01.usa.net
165.212.12.3	PTR	bcdvg003.cms.usa.net
165.212.12.3	A	se.usa.net
165.212.12.7	A	dnspri01-old.usa.net
165.212.12.12	A	uzdvg002.cms.usa.net
165.212.12.120	PTR	solaris01.cms.usa.net
165.212.12.127	A+PTR	ldap.postoffice.net
165.212.12.129	A+PTR	updvg002.cms.usa.net
165.212.12.131	A	uldvg131.cms.usa.net
165.212.12.132	A	updvg003.cms.usa.net
165.212.13.3	PTR	cbcst004.cms.usa.net
165.212.13.251	A+PTR	deliver.postoffice.net
165.212.13.251	A	mail.realtydatatrust.com
165.212.13.252	A+PTR	forward.mx.net
165.212.14.253	A+PTR	pop3.postoffice.net
165.212.14.253	A	pop.postoffice.net
165.212.15.52	A+PTR	e2k.usa.net
165.212.15.53	A	backe2k.usa.net
165.212.15.223	A	emcctl01.cms.usa.net
165.212.16.11	PTR	pwdvg001.phone.com
165.212.19.242	PTR	zrdvg242-v15.usa.net
165.212.20.159	PTR	mtdvt159.msl.usa.net
165.212.20.211	PTR	newhawk.usa.net
165.212.20.215	PTR	amast-sun.usa.net
165.212.21.1	PTR	sel.usa.net
165.212.21.1	A	mailadmin.net
165.212.22.5	PTR	avsrv.corp.usa.net
165.212.22.31	A+PTR	onyx-prod.usa.net
165.212.22.32	A+PTR	onyx-web.usa.net
165.212.22.33	A+PTR	onyx-report.usa.net
165.212.22.34	A	onyx-print-list.usa.net
165.212.22.101	A	specialoffers.usa.net
165.212.22.102	A	gs.adminportal.com
165.212.22.107	A	adminportal.com
165.212.22.107	A	testdrive.usa.net
165.212.32.3	PTR	mail.gspsf.com
165.212.32.151	PTR	uadvg201.cms.usa.net
165.212.32.152	PTR	uadvg202.cms.usa.net
165.212.48.1	PTR	exch.usa.net
165.212.48.2	PTR	mailexch.usa.net
165.212.49.1	PTR	mail.messagesonline.net
165.212.49.1	A	exchprod.usa.net
165.212.49.1	A	messagesonline.net
165.212.49.49	A	nethawk.usa.net
165.212.49.119	PTR	per5-test-glpi1.test.usa.net
165.212.49.201	A	outbound-gw.messagesonline.net
165.212.49.212	A	vpn3060.messagesonline.net
165.212.49.214	A	vpnvip.messagesonline.net
165.212.49.249	A	tacacs.usa.net
165.212.54.6	A	ms02.mailsafe.usa.net
165.212.54.10	A	mailsafe.usa.net
165.212.54.10	A	perimeterusa.mailsafe.usa.net
165.212.54.26	A	atlancoast.mailsafe.usa.net
165.212.54.52	A	perimeterusa.mailsafe.usa.net
165.212.54.52	A	cbsecuremail.mailsafe.usa.net
165.212.54.202	A	cbsecuremail.mailsafe.usa.net
165.212.54.204	A	rpsbenefits.mailsafe.usa.net
165.212.55.17	A	mailsafe.barrongannon.com
165.212.55.23	A	pdnb.mailsafe.usa.net
165.212.55.54	A+PTR	dnsext01.usa.net
165.212.55.54	A	cndvg054.usa.net
165.212.55.79	A	guyleopold.mailsafe.usa.net
165.212.55.79	A	mailsafe.guyleopold.com
165.212.55.131	A	bankofmagnolia.mailsafe.usa.net
165.212.55.157	A	weberstatecu.mailsafe.usa.net
165.212.55.177	A	adjacent-tech.mailsafe.usa.net
165.212.55.192	PTR	bankatpsb.mailsafe.usa.net
165.212.55.203	A	manasquanbank.mailsafe.usa.net