Robtex

Up: 109.126.12.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 109.126.12.0/25
Down right: 109.126.12.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
109.126.12.3	PTR	109-126-12-3.eth.vladlink.net
109.126.12.3	A	mx.alfa-rekom.ru
109.126.12.3	A	mx2.alfa-rekom.ru
109.126.12.162	PTR	109-126-12-162.eth.vladlink.net
109.126.12.188	A+PTR	mail.domochag.ru