Robtex

Up: 203.113.144.0/21
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Down left: 203.113.144.0/23
Down right: 203.113.146.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
203.113.144.84	A	mail.spartronics.com
203.113.144.214	A	mail.stickleyinternational.com
203.113.144.220	A	mail.estecphutho.com
203.113.144.221	A	mail.estecvina.com
203.113.145.120	PTR	mail.clovervn.com
203.113.145.149	PTR	mail.acbs.com.vn
203.113.145.204	PTR	mail.acb.com.vn
203.113.145.223	PTR	mail.aict.com.vn
203.113.145.225	A	mailserver.cpvina.com
203.113.146.20	PTR	mail.hmm.com.vn
203.113.146.35	PTR	mail.diltd.com.vn
203.113.146.90	PTR	webmail.lacviet.com.vn
203.113.146.146	PTR	mail.joonsaigon.com
203.113.146.146	PTR	mail.pk-saigontwo.com
203.113.146.146	PTR	mail.pungkookvn.com
203.113.146.182	PTR	mail1.globaldyeing.com
203.113.146.182	A	mail.globalhantex.com
203.113.146.182	A	mail.globaldyeing.com
203.113.146.186	PTR	mail.travinh.gov.vn
203.113.146.194	PTR	mail.scavi.com.vn
203.113.146.213	PTR	mail.tvs.vn
203.113.146.235	PTR	mail.hsvina.com
203.113.146.235	A	hsvina.com
203.113.146.235	A	mx3.hsvina.com
203.113.146.238	A+PTR	mail.hsvina.com
203.113.146.238	A	hsvina.com
203.113.146.238	A	mx3.hsvina.com
203.113.147.11	A+PTR	mail.esprintavn.com
203.113.147.47	A	lqmgarenashop.com
203.113.147.171	PTR	smtp.cathaylife.com.vn
203.113.147.177	A	fit.hcmute.edu.vn
203.113.147.177	A	aao.hcmute.edu.vn
203.113.147.177	A	feee.hcmute.edu.vn
203.113.147.179	PTR	mail1.hcmute.edu.vn
203.113.147.179	A	dkmh.hcmute.edu.vn
203.113.147.183	A	vinacel.hcmute.edu.vn
203.113.147.184	A	baigiai.vn
203.113.147.184	A	anhduc-co.com
203.113.147.186	A	10110clc.com
203.113.147.186	A	dkmh.hcmute.edu.vn