Robtex

Up: 217.23.128.0/24
Can't show all results, try to descend to a more specific CIDR
Down left: 217.23.128.0/26
Down right: 217.23.128.64/26
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
217.23.128.0	PTR	unused.caravan.ru
217.23.128.1	PTR	ns.caravan.ru
217.23.128.15	PTR	ppp-15.max6k.caravan.ru
217.23.128.16	PTR	ppp-16.max6k.caravan.ru
217.23.128.22	PTR	unused.caravan.ru
217.23.128.31	PTR	ppp-31.max6k.caravan.ru
217.23.128.32	PTR	ppp-32.max6k.caravan.ru
217.23.128.34	PTR	unused.caravan.ru
217.23.128.42	PTR	unused.caravan.ru
217.23.128.42	A	ppp-42.max6k.caravan.ru
217.23.128.44	PTR	unused.caravan.ru
217.23.128.44	A	ppp-44.max6k.caravan.ru
217.23.128.45	PTR	unused.caravan.ru
217.23.128.50	PTR	ppp-50.max6k.caravan.ru
217.23.128.58	A+PTR	ppp-58.max6k.caravan.ru
217.23.128.63	PTR	ppp-63.max6k.caravan.ru
217.23.128.64	PTR	ppp-64.max6k.caravan.ru
217.23.128.68	A+PTR	ws3.smsc.ru
217.23.128.68	A	www2.smsc.ru
217.23.128.68	A	send2.smsc.ru
217.23.128.69	PTR	unused.caravan.ru
217.23.128.69	A	ppp-69.max6k.caravan.ru
217.23.128.73	A	ppp-73.max6k.caravan.ru
217.23.128.74	A+PTR	mail3.smscentre.com
217.23.128.75	A+PTR	ws4.smsc.ru
217.23.128.85	PTR	ppp-85.max6k.caravan.ru
217.23.128.90	A+PTR	ppp-90.max6k.caravan.ru
217.23.128.120	PTR	unused.caravan.ru
217.23.128.127	PTR	ppp-127.max6k1.caravan.ru