Robtex

Up: 203.89.30.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 203.89.31.0/25
Down right: 203.89.31.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
203.89.31.1	PTR	sby-ip-31-1.datautama.net.id
203.89.31.10	PTR	sby-ip-31-10.datautama.net.id
203.89.31.10	A	0.id.pool.ntp.org
203.89.31.11	A+PTR	saturnus.datautama.net.id
203.89.31.11	A	smtp.sby.datautama.net.id
203.89.31.12	A+PTR	uranus.datautama.net.id
203.89.31.12	A	smtp.sby.datautama.net.id
203.89.31.12	A	nospam.datautama.net.id
203.89.31.13	A+PTR	ns5.datautama.net.id
203.89.31.13	A	0.id.pool.ntp.org
203.89.31.13	A	asia.pool.ntp.org
203.89.31.14	A+PTR	outgoing1.datautama.net.id
203.89.31.14	A	nospam.datautama.net.id
203.89.31.14	A	venus.datautama.net.id
203.89.31.15	PTR	sby-ip-31-15.datautama.net.id
203.89.31.16	PTR	sby-ip-31-16.datautama.net.id
203.89.31.17	PTR	sby-ip-31-17.datautama.net.id
203.89.31.34	PTR	sby-ip-31-34.datautama.net.id
203.89.31.37	PTR	sby-ip-31-37.datautama.net.id
203.89.31.40	PTR	sby-ip-31-40.datautama.net.id
203.89.31.64	PTR	sby-ip-31-64.datautama.net.id
203.89.31.75	PTR	sby-ip-31-75.datautama.net.id
203.89.31.77	PTR	sby-ip-31-77.datautama.net.id
203.89.31.85	PTR	sby-ip-31-85.datautama.net.id
203.89.31.96	PTR	sby-ip-31-96.datautama.net.id
203.89.31.106	PTR	sby-ip-31-106.datautama.net.id
203.89.31.111	PTR	sby-ip-31-111.datautama.net.id
203.89.31.113	PTR	sby-ip-31-113.datautama.net.id
203.89.31.126	PTR	sby-ip-31-126.datautama.net.id
203.89.31.169	PTR	sby-ip-31-169.datautama.net.id
203.89.31.199	PTR	sby-ip-31-199.datautama.net.id
203.89.31.216	PTR	sby-ip-31-216.datautama.net.id
203.89.31.234	PTR	sby-ip-31-234.datautama.net.id