Robtex

Up: 213.87.100.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 213.87.100.0/25
Down right: 213.87.100.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
213.87.100.1	PTR	host.mrdv-5.mtsnet.ru
213.87.100.9	PTR	host.mrdv-5.mtsnet.ru
213.87.100.14	PTR	host.mrdv-5.mtsnet.ru
213.87.100.28	PTR	host.mrdv-5.mtsnet.ru
213.87.100.42	PTR	host.mrdv-5.mtsnet.ru
213.87.100.42	A	ns2.redroll.ru
213.87.100.42	A	ns2.vlhosting.ru
213.87.100.46	PTR	host.mrdv-5.mtsnet.ru
213.87.100.46	A	teckel.space
213.87.100.50	A	mail.bayanay.net
213.87.100.50	A	mail.ns1992.ru
213.87.100.52	A	ussuri-art.ru
213.87.100.52	A	valeolog-tm.ru
213.87.100.52	A	mail.blagodatsp.ru
213.87.100.60	PTR	mx.gdg.ru
213.87.100.60	A	mx1.g-george.com
213.87.100.142	PTR	host.mrdv-5.mtsnet.ru
213.87.100.150	A+PTR	mail.vyp.vedtransservis.com
213.87.100.156	A	mail.zevsparts.ru
213.87.100.170	A	adm.mxgroup.ru
213.87.100.174	PTR	host.mrdv-5.mtsnet.ru
213.87.100.174	A	mxgroup.ru
213.87.100.197	PTR	host.mrdv-5.mtsnet.ru
213.87.100.197	A	wan2.vladcosmetic.com
213.87.100.210	PTR	host.mrdv-5.mtsnet.ru
213.87.100.210	A	ankora-v.ru
213.87.100.212	A+PTR	mail.vostokstr.ru
213.87.100.212	A	emiko.mooo.com
213.87.100.219	A+PTR	viagra.kamlines.ru
213.87.100.219	A	kamlines.ru
213.87.100.219	A	psco.su
213.87.100.250	A	mx2.sollers-fe.com