Robtex

Up: 141.223.0.0/17
Can't show all results, try to descend to a more specific CIDR
Down left: 141.223.0.0/19
Down right: 141.223.32.0/19
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
141.223.1.0	A+PTR	messaging-service.postech.ac.kr
141.223.1.1	A	mx.postech.kr
141.223.1.1	A	mx.postech.edu
141.223.1.1	A	imap.postech.ac.kr
141.223.1.2	PTR	dns.postech.ac.kr
141.223.1.2	PTR	ns.postech.ac.kr
141.223.1.2	PTR	ns1.postech.ac.kr
141.223.1.3	PTR	old-webmail.postech.ac.kr
141.223.1.71	A	imap.postech.ac.kr
141.223.1.71	A	mail.postech.ac.kr
141.223.1.71	A	webmail.postech.ac.kr
141.223.1.151	A	hsm.postech.ac.kr
141.223.1.151	A	cee.postech.ac.kr
141.223.1.151	A	webhosting.postech.ac.kr
141.223.1.205	PTR	ipmp.postech.ac.kr
141.223.1.253	A	nstest.postech.ac.kr
141.223.2.2	A+PTR	shell.postech.ac.kr
141.223.2.2	A+PTR	shell1.postech.ac.kr
141.223.2.3	A+PTR	shell2.postech.ac.kr
141.223.3.0	A+PTR	library-1.postech.ac.kr
141.223.3.1	PTR	povis.postech.ac.kr
141.223.3.1	A+PTR	course.postech.ac.kr
141.223.3.2	A+PTR	gwap.postech.ac.kr
141.223.3.2	PTR	gw.postech.ac.kr
141.223.3.5	A	eccap.postech.ac.kr
141.223.3.83	A	sms.postech.ac.kr
141.223.3.113	A	lms.postech.ac.kr
141.223.4.0	A+PTR	library-1.postech.ac.kr
141.223.4.0	PTR	posis-service.postech.ac.kr
141.223.4.10	A	posiswasg.postech.ac.kr
141.223.4.12	A	lg-db.postech.ac.kr
141.223.5.0	A+PTR	library-1.postech.ac.kr
141.223.5.0	PTR	web-service.postech.ac.kr
141.223.5.10	A+PTR	www-old.postech.ac.kr
141.223.5.10	A	mml.postech.ac.kr
141.223.5.10	A	mpi-korea.org
141.223.5.12	PTR	www2.postech.ac.kr
141.223.5.70	A	csm.postech.ac.kr
141.223.5.75	A	csm.postech.ac.kr
141.223.5.75	A	paust.postech.ac.kr
141.223.5.75	A	edulab.postech.ac.kr
141.223.5.78	A	paust.postech.ac.kr
141.223.5.79	A	hss.postech.ac.kr
141.223.5.79	A	math.postech.ac.kr
141.223.5.156	PTR	mueunjae.postech.ac.kr
141.223.5.156	A	vision.postech.ac.kr
141.223.5.156	A	donation.postech.ac.kr
141.223.5.166	A	postech.biz
141.223.5.166	A	mail.postech.biz
141.223.5.210	A+PTR	admission.postech.ac.kr
141.223.7.0	A	ipstorage-service.postech.ac.kr
141.223.7.11	PTR	mx1-ip4700-int0-nouse.postech.ac.kr
141.223.7.15	A	mx2-ip4700-int0-nouse.postech.ac.kr
141.223.7.17	A	mx2-ip4700-int1.postech.ac.kr
141.223.7.18	A	mx2-ip4700-int1.postech.ac.kr
141.223.7.20	A	ip4700-int1.postech.ac.kr
141.223.7.96	A	drhub.postech.ac.kr
141.223.7.101	A	afsdb1.postech.ac.kr
141.223.7.102	A	afsdb2.postech.ac.kr
141.223.7.103	A	afsdb3.postech.ac.kr
141.223.7.151	A+PTR	wmail-ip4700.postech.ac.kr
141.223.8.0	A+PTR	not-reserved.postech.ac.kr
141.223.10.0	A+PTR	not-reserved.postech.ac.kr
141.223.11.0	A+PTR	not-reserved.postech.ac.kr
141.223.15.0	A+PTR	not-reserved.postech.ac.kr
141.223.15.96	A+PTR	dr-firewall.postech.ac.kr
141.223.16.0	A	not-reserved.postech.ac.kr
141.223.16.54	PTR	libanswers.postech.ac.kr
141.223.17.0	A+PTR	not-reserved.postech.ac.kr
141.223.18.0	A+PTR	not-reserved.postech.ac.kr
141.223.19.0	A+PTR	not-reserved.postech.ac.kr
141.223.20.0	A+PTR	not-reserved.postech.ac.kr
141.223.21.0	A+PTR	not-reserved.postech.ac.kr
141.223.22.8	A	cool.postech.ac.kr
141.223.23.11	A	csclab.postech.ac.kr
141.223.25.0	A+PTR	not-reserved.postech.ac.kr
141.223.26.0	A+PTR	not-reserved.postech.ac.kr
141.223.27.0	A+PTR	not-reserved.postech.ac.kr
141.223.29.40	A	susun.postech.ac.kr
141.223.30.0	A+PTR	not-reserved.postech.ac.kr
141.223.31.0	A+PTR	not-reserved.postech.ac.kr
141.223.35.0	A+PTR	not-reserved.postech.ac.kr
141.223.36.0	A+PTR	not-reserved.postech.ac.kr
141.223.37.0	A+PTR	not-reserved.postech.ac.kr
141.223.37.132	PTR	cgpweb.postech.ac.kr
141.223.37.132	A	tjchoice.or.kr
141.223.37.132	A	cgp.ibs.re.kr
141.223.38.1	A+PTR	math.postech.ac.kr
141.223.38.3	A+PTR	com2mac.postech.ac.kr
141.223.38.3	PTR	jhkwak.postech.ac.kr
141.223.39.0	A+PTR	not-reserved.postech.ac.kr
141.223.41.9	A	ph.postech.ac.kr
141.223.41.24	A	magnon2.postech.ac.kr
141.223.41.66	A+PTR	phypc26.postech.ac.kr
141.223.42.160	A	salkpcnt.postech.ac.kr
141.223.44.2	A+PTR	e-mfg.postech.ac.kr
141.223.44.2	A+PTR	ipse.postech.ac.kr
141.223.44.2	A+PTR	u-gpe.postech.ac.kr
141.223.45.160	A	moohyunpc2.postech.ac.kr
141.223.46.90	A	osskorea.com
141.223.50.0	A+PTR	not-reserved.postech.ac.kr
141.223.54.1	A+PTR	seobuk1f-1.postech.ac.kr
141.223.54.4	A+PTR	seobuk2f-1.postech.ac.kr
141.223.54.93	A	dongbuk1f-1.postech.ac.kr
141.223.54.96	A	dongbuk2f-1.postech.ac.kr
141.223.57.200	A	newbb8-1.postech.ac.kr
141.223.58.0	A	not-reserved.postech.ac.kr
141.223.61.228	A	atom.postech.ac.kr