Robtex

Up: 121.243.32.0/20
Can't show all results, try to descend to a more specific CIDR
Down left: 121.243.32.0/22
Down right: 121.243.36.0/22
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
121.243.32.2	PTR	121.243.32.2.static-chennai.vsnl.net.in
121.243.32.70	PTR	121.243.32.70.static-chennai.vsnl.net.in
121.243.32.110	PTR	121.243.32.110.static-chennai.vsnl.net.in
121.243.33.212	PTR	121.243.33.212.static-chennai.vsnl.net.in
121.243.35.6	A	mail.sivabulk.com
121.243.35.6	A	mail.rudhraenergy.com
121.243.35.9	PTR	121.243.35.9.static-chennai.vsnl.net.in
121.243.35.9	A	alexandredeparis-accessories.co.in
121.243.35.12	A	crossbridgeprojects.com
121.243.35.24	PTR	121.243.35.24.static-chennai.vsnl.net.in
121.243.35.195	PTR	qhost.qatalystechnologies.com
121.243.35.195	A	mail.qatalystechnologies.com
121.243.35.204	A	qsmail.qsourceglobal.com
121.243.35.204	A	mail.qsourceglobal.com
121.243.35.209	PTR	121.243.35.209.static-chennai.vsnl.net.in
121.243.35.209	A	dynamicsq.com
121.243.35.209	A	qatalystechnologies.com
121.243.36.146	PTR	121.243.36.146.static-chennai.vsnl.net.in
121.243.36.154	PTR	121.243.36.154.static-chennai.vsnl.net.in
121.243.36.216	PTR	121.243.36.216.static-chennai.vsnl.net.in
121.243.37.117	PTR	121.243.37.117.static-chennai.vsnl.net.in
121.243.37.117	A	login.craftsmanautomation.com
121.243.39.6	A	landmark-tata.com
121.243.39.131	PTR	121.243.39.131.static-chennai.vsnl.net.in
121.243.39.226	PTR	121.243.39.226.static-chennai.vsnl.net.in