Robtex

Up: 203.13.40.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 203.13.40.0/25
Down right: 203.13.40.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
203.13.40.6	A	ns11.hetch.in
203.13.40.6	A	ns12.zabby.in
203.13.40.6	A	ns12.hetch.in
203.13.40.10	A	in.mx1.mailhostbox.com
203.13.40.11	A	in.spf.outbound.mailhostbox.com
203.13.40.12	A+PTR	in.cp.mailhostbox.com
203.13.40.13	A	in.spf.outbound.mailhostbox.com
203.13.40.14	A+PTR	in.cp.mailhostbox.com
203.13.40.15	PTR	in.mx1.mailhostbox.com
203.13.40.16	A+PTR	in.mx2.mailhostbox.com
203.13.40.17	A+PTR	in.mx3.mailhostbox.com
203.13.40.18	A+PTR	in.mailforward.mailhostbox.com
203.13.40.19	A+PTR	in.mailforward.mailhostbox.com
203.13.40.20	A+PTR	in.mailforward.mailhostbox.com
203.13.40.21	A+PTR	in.mailforward.mailhostbox.com
203.13.40.22	A+PTR	in.mailforward.mailhostbox.com
203.13.40.23	A+PTR	in.mailforward.mailhostbox.com
203.13.40.25	A	mail.vsnl.in
203.13.40.25	A	giasbma.vsnl.net.in
203.13.40.25	A	in.pop.mailhostbox.com
203.13.40.27	A	mail.vsnl.in
203.13.40.27	A	giasbma.vsnl.net.in
203.13.40.27	A	in.pop.mailhostbox.com
203.13.40.28	A+PTR	in.outbound.mailhostbox.com
203.13.40.28	A	in.spf.outbound.mailhostbox.com
203.13.40.29	A+PTR	in-ob1-1.mailhostbox.com
203.13.40.29	A	in.spf.outbound.mailhostbox.com
203.13.40.30	A+PTR	in-ob1-2.mailhostbox.com
203.13.40.30	A	in.spf.outbound.mailhostbox.com
203.13.40.31	A+PTR	in-ob1-3.mailhostbox.com
203.13.40.31	A	in.spf.outbound.mailhostbox.com
203.13.40.32	A+PTR	in-ob1-4.mailhostbox.com
203.13.40.32	A	in.spf.outbound.mailhostbox.com
203.13.40.33	A+PTR	in.smtp.mailhostbox.com
203.13.40.33	A	smtp.vsnl.com
203.13.40.34	A+PTR	in.outbound.mailhostbox.com
203.13.40.34	A	in.spf.outbound.mailhostbox.com
203.13.40.35	A+PTR	in-ob2-1.mailhostbox.com
203.13.40.35	A	in.spf.outbound.mailhostbox.com
203.13.40.36	A+PTR	in-ob2-2.mailhostbox.com
203.13.40.36	A	in.spf.outbound.mailhostbox.com
203.13.40.37	A+PTR	in-ob2-3.mailhostbox.com
203.13.40.37	A	in.spf.outbound.mailhostbox.com
203.13.40.38	A+PTR	in-ob2-4.mailhostbox.com
203.13.40.38	A	in.spf.outbound.mailhostbox.com
203.13.40.39	A+PTR	in.smtp.mailhostbox.com
203.13.40.39	A	smtp.vsnl.com
203.13.40.41	A+PTR	in.webmail.mailhostbox.com
203.13.40.41	A	login.vsnl.com
203.13.40.43	A+PTR	in.webmail.mailhostbox.com
203.13.40.43	A	login.vsnl.com
203.13.40.44	A+PTR	mailserver.myorderbox.com
203.13.40.45	A+PTR	mailserver.myorderbox.com
203.13.40.45	A	supportnation.com
203.13.40.46	A+PTR	mailserver.myorderbox.com
203.13.40.47	A+PTR	mailserver.myorderbox.com
203.13.40.47	A	chat.resellerclub.com
203.13.40.48	A+PTR	mailserver.myorderbox.com
203.13.40.49	A+PTR	mailserver.myorderbox.com
203.13.40.49	A	anytimesupport.co
203.13.40.50	A+PTR	mailserver.myorderbox.com
203.13.40.51	A+PTR	mailserver.myorderbox.com
203.13.40.52	A+PTR	mailserver.myorderbox.com
203.13.40.53	A+PTR	mailserver.myorderbox.com
203.13.40.54	A	mailserver.myorderbox.com
203.13.40.56	A+PTR	1-bom-smtp-in.restful.email
203.13.40.57	A+PTR	1-bom-smtp-out.restful.email
203.13.40.58	A+PTR	2-bom-smtp-out.restful.email
203.13.40.59	A+PTR	3-bom-smtp-out.restful.email
203.13.40.60	A+PTR	4-bom-smtp-out.restful.email
203.13.40.61	A+PTR	5-bom-smtp-out.restful.email
203.13.40.62	A+PTR	6-bom-smtp-out.restful.email
203.13.40.63	A+PTR	7-bom-smtp-out.restful.email
203.13.40.101	A	ns15.zabby.in
203.13.40.101	A	ns16.hetch.in
203.13.40.101	A	ns15.hetch.in
203.13.40.151	A	wh2.zabby.in