Robtex

Up: 123.49.12.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 123.49.12.0/25
Down right: 123.49.12.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
123.49.12.2	A+PTR	padma.bttb.net.bd
123.49.12.3	PTR	host3.btcl.net.bd
123.49.12.3	A+PTR	gorai.bttb.net.bd
123.49.12.4	PTR	host4.btcl.net.bd
123.49.12.4	A	www.rab.gov.bd
123.49.12.79	PTR	host79.btcl.net.bd
123.49.12.112	A+PTR	dns.bd
123.49.12.131	A	xn--94bcy3esc8fb.xn--54b7fta0cc
123.49.12.132	PTR	host132.btcl.net.bd
123.49.12.133	A	chuadangacollege.gov.bd
123.49.12.133	A	www.beautyshoppers.com.bd
123.49.12.133	A	www.chhar.com.bd
123.49.12.136	A	www.bttb.net.bd
123.49.12.136	A	www.btcl.net.bd
123.49.12.140	PTR	host140.btcl.net.bd
123.49.12.148	PTR	host148.btcl.net.bd
123.49.12.148	A	dns.btcl.net.bd
123.49.12.148	A	dns.bttb.net.bd
123.49.12.149	A	gorai.bttb.net.bd
123.49.12.149	A	slave.bttb.net.bd
123.49.12.149	A	slave.btcl.net.bd
123.49.12.151	PTR	host151.btcl.net.bd
123.49.12.155	PTR	host155.btcl.net.bd
123.49.12.155	A	www.btcl.gov.bd
123.49.12.155	A	btcl.gov.bd
123.49.12.161	PTR	host161.btcl.net.bd
123.49.12.162	PTR	host162.btcl.net.bd
123.49.12.182	PTR	host182.btcl.net.bd
123.49.12.182	A	dns2.bttb.net.bd
123.49.12.182	A	dns2.btcl.net.bd
123.49.12.185	PTR	host185.btcl.net.bd
123.49.12.195	PTR	host195.btcl.net.bd
123.49.12.231	PTR	host231.btcl.net.bd
123.49.12.237	PTR	host237.btcl.net.bd