Robtex

Up: 220.231.88.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 220.231.88.0/23
Down right: 220.231.90.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
220.231.88.21	PTR	localhost
220.231.88.21	A	mail.premierenglish.net
220.231.88.31	PTR	localhost
220.231.88.32	PTR	localhost
220.231.88.70	PTR	localhost
220.231.88.100	A+PTR	mail.generali-life.com.vn
220.231.88.107	PTR	localhost
220.231.88.107	A	genvita.vn
220.231.88.107	A	www.genvita.vn
220.231.88.109	A	vita-song-nhu-y.genvita.vn
220.231.88.110	A	mail.generalivietnam.com
220.231.88.115	PTR	localhost
220.231.88.115	A	genext.vn
220.231.88.115	A	www.genext.vn
220.231.88.116	PTR	localhost
220.231.88.117	PTR	localhost
220.231.88.117	A	genlink.generali-life.com.vn
220.231.88.119	PTR	localhost
220.231.88.119	A	ginquiry.generali-life.com.vn
220.231.88.120	A	cas.generali-life.com.vn
220.231.88.185	PTR	mail1.ajinomoto.com.vn
220.231.88.194	PTR	localhost
220.231.88.196	PTR	localhost
220.231.88.196	A	mail.tinhyeumongmo.vn
220.231.88.196	A	mail.mamnonbambi.edu.vn
220.231.88.198	PTR	localhost
220.231.88.198	A	ttcgroup.vn
220.231.88.203	PTR	localhost
220.231.88.203	A	danghuynh.vn
220.231.88.203	A	tanisugar.vn
220.231.88.205	PTR	mail.ttcland.vn
220.231.88.205	A+PTR	mail.yersin.edu.vn
220.231.88.205	PTR	mail.duongnuoctrong.vn
220.231.88.206	PTR	mail.attapeusugar.la
220.231.88.206	PTR	mail.toanhaivan.com.vn
220.231.88.206	PTR	mail.ttcplastic.vn
220.231.88.242	PTR	localhost
220.231.88.242	A	mail.thunglungtinhyeu.vn
220.231.89.35	A+PTR	mail2.theodorealexander.com
220.231.89.35	A	mx2.theodorealexander.com
220.231.89.50	PTR	mail.shingmark.com.vn
220.231.89.72	PTR	localhost
220.231.89.77	PTR	localhost
220.231.89.77	A	mail.pvd.vn
220.231.89.83	A	mail1.globaldyeing.com
220.231.89.105	PTR	mail.fashiongarments.com
220.231.89.105	A	mx3.fashiongarments.com
220.231.89.106	A	fashiongarments.com
220.231.89.109	A+PTR	mail.fashiongarments.com
220.231.89.109	A	mx1.fashiongarments.com
220.231.89.185	PTR	localhost
220.231.89.185	A	ns1.suckhoevang.vn
220.231.89.185	A	ns1.gpdd.vn
220.231.89.186	PTR	mail.tma.com.vn
220.231.89.186	A	mail.tmasolutions.com
220.231.89.186	A	mail.ttc.edu.vn
220.231.89.245	PTR	localhost
220.231.90.59	PTR	mx2.dai-ichi-life.com.vn
220.231.90.61	A	ns2.dai-ichi-life.net
220.231.90.99	PTR	mail.tecs.com.vn
220.231.90.107	PTR	smtp.pvgas.com.vn
220.231.90.150	A+PTR	smtp.cathay-ins.com.vn
220.231.90.150	A	ns1.cathay-ins.com.vn
220.231.90.154	A	ns2.cathay-ins.com.vn
220.231.90.155	A	www.cathay-ins.com.vn
220.231.90.155	A	cathay-ins.com.vn
220.231.91.58	A	ns3.pvgas.com.vn
220.231.91.114	PTR	localhost
220.231.91.114	A	mail.tinnghia.com.vn
220.231.91.169	PTR	localhost
220.231.91.195	PTR	localhost
220.231.91.237	PTR	localhost
220.231.91.238	PTR	localhost
220.231.91.242	PTR	mail.hoianindochine.com
220.231.91.242	PTR	mail.sacomreal.com
220.231.91.242	PTR	mail.thanhbinhhotelsgroup.com