Robtex

Up: 64.56.90.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 64.56.91.0/25
Down right: 64.56.91.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
64.56.91.2	A+PTR	ircc.net
64.56.91.2	A+PTR	mimir.irsc.edu
64.56.91.2	A	mimir.ircc.net
64.56.91.3	A+PTR	mercury.irsc.edu
64.56.91.3	A+PTR	mercury.ircc.net
64.56.91.3	A	irsc.edu
64.56.91.5	A+PTR	barracuda.ircc.net
64.56.91.11	A	ircc.cc.fl.us
64.56.91.11	A	cisco.irsc.edu
64.56.91.15	A+PTR	ex4.irsc.edu
64.56.91.39	A+PTR	portal.irsc.edu
64.56.91.39	A	portal.ircc.cc.fl.us
64.56.91.39	A	www.ircc.cc.fl.us
64.56.91.45	A+PTR	asa1.irsc.edu
64.56.91.47	A+PTR	asa-noc-dr.irsc.edu
64.56.91.150	A+PTR	view-security.irsc.edu
64.56.91.201	A+PTR	smtp1.ircc.net
64.56.91.211	A+PTR	spol.irsc.edu