Robtex

Up: 192.126.42.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 192.126.42.0/25
Down right: 192.126.42.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
192.126.42.3	A+PTR	ns2.atk.tpo.fi
192.126.42.3	PTR	tpo3.atk.tpo.fi
192.126.42.5	PTR	nalsw28-i.atk.tpo.fi
192.126.42.7	A+PTR	ns.atk.tpo.fi
192.126.42.7	A+PTR	ns1.atk.tpo.fi
192.126.42.7	A+PTR	tpo7.atk.tpo.fi