Robtex

Up: 91.217.20.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 91.217.20.0/25
Down right: 91.217.20.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
91.217.20.0	PTR	nic-network
91.217.20.1	PTR	ns4-l2.nic.ru
91.217.20.1	A	ns4.ska.su
91.217.20.1	A	ns2.7svet.ru
91.217.20.5	PTR	ns4-l3.nic.ru
91.217.20.5	A	ns2.fiscal.com.ar
91.217.20.5	A	ns34-cloud.nic.ru
91.217.20.9	A+PTR	ns4-l4.nic.ru
91.217.20.9	A	ns44-cloud.nic.ru
91.217.20.13	A+PTR	ns4-l5.nic.ru
91.217.20.13	A	tvsz.org
91.217.20.13	A	ns54-cloud.nic.ru
91.217.20.65	A+PTR	ns4-fwl2.nic.ru
91.217.20.69	A+PTR	ns4-fwl3.nic.ru
91.217.20.73	A+PTR	ns4-fwl4.nic.ru
91.217.20.77	A+PTR	ns4-fwl5.nic.ru
91.217.20.150	A+PTR	ns4-geo.nic.ru
91.217.20.170	A+PTR	ns4-com.nic.ru