Robtex

Up: 81.90.252.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 81.90.252.0/25
Down right: 81.90.252.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
81.90.252.27	PTR	gs1.graphart.cz
81.90.252.27	A	gs2.graphart.cz
81.90.252.27	A	new.graphart.cz
81.90.252.29	PTR	unassigned-81-90-252-29.ujezd.net
81.90.252.36	PTR	unassigned-81-90-252-36.ujezd.net
81.90.252.36	A	nvt.cz
81.90.252.75	A	mail.eko-program.cz
81.90.252.75	A	remote.eko-program.cz
81.90.252.90	PTR	unassigned-81-90-252-90.ujezd.net
81.90.252.91	A	smtp.mintpowertools.cz
81.90.252.125	A	mail.aluteckk.cz
81.90.252.129	PTR	unassigned-81-90-252-129.ujezd.net
81.90.252.129	A	smtp.technocore.cz
81.90.252.129	A	czkc.cz
81.90.252.145	A	ekinovic.eu
81.90.252.145	A	jampracuje.cz
81.90.252.173	PTR	unassigned-81-90-252-173.ujezd.net
81.90.252.207	PTR	unassigned-81-90-252-207.ujezd.net
81.90.252.207	A	kilahoo.cz
81.90.252.207	A	mail.kilahoo.cz
81.90.252.211	PTR	pha.josak.cz