Robtex

Up: 5.42.232.0/22
Can't show all results, try to descend to a more specific CIDR
Down left: 5.42.234.0/24
Down right: 5.42.235.0/24
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
5.42.234.15	A+PTR	mail2.isdb.org
5.42.235.14	A	traveler.isdb.org
5.42.235.15	A+PTR	mail.isdb.org
5.42.235.15	A	email.icd-idb.org
5.42.235.15	A	email.itfc-idb.org
5.42.235.16	A	reg.isdb.org
5.42.235.17	A	webmail.isdb.org
5.42.235.20	A	icd-idb.com
5.42.235.20	A	icd-idb.org
5.42.235.20	A	www.icd-idb.com
5.42.235.36	A+PTR	mail3.isdb.org
5.42.235.74	A	pushmail.isdb.org
5.42.235.129	A	vpn.isdb.org