Robtex

Up: 104.255.48.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 104.255.52.0/23
Down right: 104.255.54.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
104.255.52.11	A+PTR	ns1.cyberannex.com
104.255.52.11	A+PTR	dns1.cyberannex.com
104.255.52.11	A	dns1.cyberannex.net
104.255.52.12	A+PTR	ns2.cyberannex.com
104.255.52.12	A	dns2.cyberannex.com
104.255.52.12	A	dns2.cyberannex.net
104.255.52.15	A	exchange.cyberannex.com
104.255.52.25	PTR	www5.cyberannex.com
104.255.52.25	A	cyber-backup.com
104.255.52.253	A+PTR	barracuda.cyberannex.com
104.255.53.10	PTR	www1.cyberannex.com
104.255.53.10	A	picksystem.com
104.255.53.20	A	hygienemobileunit.com
104.255.53.20	A	parspilot.com
104.255.53.20	A	socaldentalhygiene.com
104.255.53.25	A	parspilot.com
104.255.53.25	A	onlineteaching.com
104.255.53.25	A	*.insurancepowerhouse.com
104.255.53.30	PTR	www3.cyberannex.com
104.255.53.30	A	onlineteaching.com
104.255.53.30	A	*.insurancepowerhouse.com
104.255.53.100	A	cyberannex.com
104.255.53.110	A	www.ransomemfg.com
104.255.54.2	A	mailgw.cyberannex.com
104.255.54.10	A	mail.shadab.com
104.255.54.10	A	mail.favre4ever.com
104.255.54.10	A	mail.elegantlooks.com
104.255.54.20	A+PTR	mail2.cyberannex.com
104.255.54.20	A	mail.tricata.com
104.255.54.100	A	mail.cyberannex.com
104.255.54.100	A	mail.sysdesign.net
104.255.54.100	A	mail.2222.net
104.255.54.102	A	mail.594graffiti.com
104.255.54.104	A	mail.aminloo.com
104.255.54.106	A+PTR	mail.fireguardians.com
104.255.54.107	A	mail.goids.com
104.255.54.108	A+PTR	mail.insurancepowerhouse.com
104.255.54.109	A	mail.meeder.com
104.255.54.110	A	mail.ransomemfg.com
104.255.54.111	A	mail.necenvironmental.com
104.255.54.112	A	mail.cyberefax.com
104.255.54.114	PTR	mail.greenaireng.com
104.255.54.114	A	mail.onlineteaching.com
104.255.54.115	A+PTR	mail.parsmail.com
104.255.54.115	A	mail.parspilot.com
104.255.54.116	A+PTR	mail.phcsi.com
104.255.54.117	PTR	mail.socaldentalhyienegroup.com
104.255.54.117	A	mail.mobilehygieneunit.com
104.255.54.118	A	mail.talkmotion.com
104.255.55.123	A+PTR	xlineusa.com
104.255.55.123	A+PTR	webtrack.xlineusa.com
104.255.55.123	A+PTR	*.xlineusa.com