Robtex

Up: 220.231.120.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 220.231.124.0/23
Down right: 220.231.126.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
220.231.124.5	PTR	mail.mod.gov.vn
220.231.124.6	PTR	localhost
220.231.124.17	PTR	mailfilter-in.th35.com.vn
220.231.124.35	PTR	localhost
220.231.124.39	PTR	localhost
220.231.124.52	PTR	localhost
220.231.124.62	PTR	localhost
220.231.124.153	PTR	localhost
220.231.124.189	PTR	localhost
220.231.124.205	PTR	localhost
220.231.124.211	PTR	localhost
220.231.124.213	PTR	localhost
220.231.124.222	PTR	localhost
220.231.125.126	PTR	localhost
220.231.125.138	PTR	localhost
220.231.125.182	PTR	localhost
220.231.126.103	PTR	localhost
220.231.126.113	PTR	localhost
220.231.126.117	PTR	localhost
220.231.126.117	A	baohiemthatnghiep.vn
220.231.126.117	A	vieclamhanoi.net
220.231.126.120	PTR	localhost
220.231.126.120	A	ldnn.trinam.com.vn
220.231.126.120	A	18001567.vn
220.231.126.121	PTR	localhost
220.231.126.121	A	vtick.com
220.231.126.123	PTR	localhost
220.231.126.123	A	vieclamhanoi.net
220.231.126.124	A	viecmienphi.com
220.231.126.125	A	daotao.vieclamvietnam.gov.vn
220.231.126.125	A	hongheovinhphuc.com
220.231.126.126	PTR	localhost
220.231.126.126	A	web.vieclamvietnam.gov.vn
220.231.126.129	PTR	localhost
220.231.126.132	A	sodepvtc.com
220.231.126.133	PTR	localhost
220.231.126.133	A	*.vieclamvietnam.gov.vn
220.231.126.145	A+PTR	mail.chinhphu.vn
220.231.126.146	PTR	localhost
220.231.126.147	A+PTR	mx1.chinhphu.vn
220.231.126.218	PTR	localhost
220.231.126.218	A	www.svic.vn
220.231.126.218	A	svic.vn
220.231.127.1	PTR	localhost
220.231.127.3	PTR	localhost
220.231.127.4	PTR	localhost
220.231.127.6	PTR	localhost
220.231.127.9	PTR	localhost
220.231.127.10	PTR	localhost
220.231.127.11	PTR	localhost
220.231.127.12	PTR	localhost
220.231.127.255	PTR	localhost