Robtex

Up: 31.21.0.0/16
Can't show all results, try to descend to a more specific CIDR
Down left: 31.21.0.0/18
Down right: 31.21.64.0/18

IP	Type	Hostname
31.21.29.52	A+PTR	52-29-21-31.ftth.glasoperator.nl
31.21.29.244	A+PTR	244-29-21-31.ftth.glasoperator.nl
31.21.41.165	A+PTR	165-41-21-31.ftth.glasoperator.nl
31.21.41.165	A	kindermerkkledingonline.nl
31.21.46.49	A+PTR	49-46-21-31.ftth.glasoperator.nl
31.21.46.49	A	atio.nl
31.21.46.49	A	atio.mooo.com
31.21.61.226	A+PTR	226-61-21-31.ftth.glasoperator.nl
31.21.61.226	A	bearpowenerji.com
31.21.64.89	A	webdiensten.nu
31.21.67.37	A+PTR	37-67-21-31.ftth.glasoperator.nl
31.21.77.204	A+PTR	204-77-21-31.ftth.glasoperator.nl
31.21.77.204	A	stream4you.nl
31.21.77.239	A+PTR	239-77-21-31.ftth.glasoperator.nl
31.21.77.239	A	js103.nl
31.21.90.67	A+PTR	67-90-21-31.ftth.glasoperator.nl
31.21.97.16	A+PTR	16-97-21-31.ftth.glasoperator.nl
31.21.108.163	A+PTR	163-108-21-31.ftth.glasoperator.nl
31.21.110.71	A+PTR	71-110-21-31.ftth.glasoperator.nl
31.21.116.230	A	vps.keescommijs.com