Robtex

Up: 5.231.88.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 5.231.88.0/23
Down right: 5.231.90.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
5.231.89.36	A+PTR	ivry.eu
5.231.89.37	A+PTR	iris.ivry.eu
5.231.89.37	A	playstation4-linux.com
5.231.89.37	A	burg-honig.de
5.231.89.39	PTR	ns1.ivry.eu
5.231.89.40	A	digitalmedicalart.com
5.231.89.47	A+PTR	page-arts.de
5.231.89.47	A	page-arts.com
5.231.89.47	A	yogi-mathias.de
5.231.89.48	PTR	page-arts.com
5.231.89.48	A	gutmann-partner.com
5.231.89.48	A	mito-portal.com
5.231.89.51	A	ivry.cloud
5.231.89.53	A+PTR	ns1.ivry.cloud
5.231.89.53	A	mail.seelen-welt.de
5.231.89.53	A	seelen-welt.de
5.231.89.54	PTR	deutschewebdesign.de
5.231.90.10	A	www.xn--mazinga-umzge-6ob.com
5.231.90.10	A	web4clans.com
5.231.91.50	A+PTR	resemblesofbooks.com
5.231.91.194	A+PTR	amusedattraction.com
5.231.91.210	A+PTR	sableschool.com