Robtex

Up: 101.0.0.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 101.0.4.0/23
Down right: 101.0.6.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
101.0.4.15	PTR	host-4-15.universal.net.id
101.0.4.22	PTR	host-4-22.universal.net.id
101.0.4.26	PTR	host-4-26.universal.net.id
101.0.4.26	A	www.lasona.com
101.0.4.26	A	lasona.com
101.0.4.62	PTR	host-4-62.universal.net.id
101.0.4.67	A+PTR	mail.e-online.co.id
101.0.4.67	A	mail.bisnisbebek.com
101.0.4.67	A	mail.emt-consulting.com
101.0.4.68	PTR	host-4-68.universal.net.id
101.0.4.68	A	semangatkerja.com
101.0.4.69	A+PTR	mail.amicollection.com
101.0.4.69	A	amicollection.com
101.0.4.71	PTR	mail.tiscometals.com
101.0.4.71	A	tokobesi.net
101.0.4.76	A+PTR	mail.grouppuncak.com
101.0.4.76	A	grouppuncak.com
101.0.4.76	A	www.grouppuncak.com
101.0.4.77	A+PTR	mail.asmarines.com
101.0.4.98	PTR	host-4-98.universal.net.id
101.0.4.130	A+PTR	mail.omuindustry.com
101.0.4.130	A	omuindustry.com
101.0.5.1	PTR	host-5-1.universal.net.id
101.0.5.6	PTR	host-5-6.universal.net.id
101.0.5.6	A	mail.agripertiwi.com
101.0.5.87	PTR	host-5-87.universal.net.id
101.0.5.87	A	z-mail.sentosagroup.net
101.0.5.90	PTR	host-5-90.universal.net.id
101.0.6.6	PTR	host-6-6.universal.net.id
101.0.6.6	A	dns1.radiantekno.com
101.0.6.23	PTR	host-6-23.universal.net.id
101.0.6.23	A	yushengtv.com
101.0.6.28	PTR	host-6-28.universal.net.id
101.0.6.28	A	kerjasukses.com
101.0.6.58	PTR	host-6-58.universal.net.id
101.0.6.69	PTR	host-6-69.universal.net.id
101.0.6.69	A	maminexpress.com
101.0.6.69	A	mciken.com
101.0.6.70	PTR	host-6-70.universal.net.id
101.0.6.82	A+PTR	mrtg.universal.net.id
101.0.6.87	A+PTR	ns1.universal.net.id
101.0.6.88	A+PTR	ns2.universal.net.id
101.0.7.1	PTR	host-7-1.universal.net.id
101.0.7.2	PTR	host-7-2.universal.net.id
101.0.7.9	PTR	host-7-9.universal.net.id
101.0.7.33	PTR	host-7-33.universal.net.id
101.0.7.88	PTR	host-7-88.universal.net.id
101.0.7.89	PTR	host-7-89.universal.net.id