Robtex

Up: 211.41.64.0/18
Can't show all results, try to descend to a more specific CIDR
Down left: 211.41.64.0/20
Down right: 211.41.80.0/20
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
211.41.69.11	PTR	nis2.paran.com
211.41.69.46	A+PTR	smartdns7.paran.com
211.41.69.47	A	smartdns8.paran.com
211.41.69.48	PTR	nis1.paran.com
211.41.78.10	A+PTR	smail2.magicn.com
211.41.78.10	A+PTR	smail2.show.co.kr
211.41.78.15	A+PTR	smail1.magicn.com
211.41.78.15	A+PTR	smail1.show.co.kr
211.41.78.20	PTR	rmail1.magicn.com
211.41.78.20	PTR	rmail1.show.co.kr
211.41.78.21	PTR	rmail2.magicn.com
211.41.78.21	PTR	rmail2.show.co.kr
211.41.80.63	A	inditv.hitel.net
211.41.80.74	PTR	sfac.or.kr
211.41.80.152	A	search3.hanmir.com
211.41.81.131	A	japan.hanmir.com
211.41.81.171	A	lottetown.hanmir.com
211.41.82.32	A	home.hanmir.co.kr
211.41.82.35	A	mail.hanmir.com
211.41.82.35	A	mail.hanmir.co.kr
211.41.82.35	A	mail.hanmir.net
211.41.82.62	PTR	mail1.openmail.paran.com
211.41.82.64	A	mail.newspim.com
211.41.82.64	A	mail.seilsa.com
211.41.82.64	A	mx.nhchemicals.com
211.41.82.65	A	mail.newspim.com
211.41.82.65	A	mail.seilsa.com
211.41.82.65	A	my.openmail.paran.com
211.41.82.66	PTR	mailex01.paran.com
211.41.82.66	PTR	mail4.openmail.paran.com
211.41.82.66	A	mail.newspim.com
211.41.82.67	PTR	mailex02.paran.com
211.41.82.98	A+PTR	mail39.hanmir.com
211.41.82.98	PTR	mail39.kttown.com
211.41.82.98	A+PTR	mail39.paran.com
211.41.82.99	PTR	smtpmail01.hanmir.com
211.41.82.99	PTR	smtpmail01.kttwon.com
211.41.82.99	PTR	smtpmail01.paran.com
211.41.82.128	A+PTR	smtpmail02.hanmir.com
211.41.82.128	PTR	smtpmail02.kttwon.com
211.41.82.128	A+PTR	smtpmail02.paran.com
211.41.82.129	PTR	mail0.hanmir.com
211.41.82.129	PTR	mail0.kttown.com
211.41.82.129	PTR	mail0.paran.com
211.41.82.167	A	mail77.paran.com
211.41.82.169	A	smail3.paran.com
211.41.82.170	A	smail2.paran.com
211.41.82.171	A	dm1.hanmir.com
211.41.82.192	A	mail16.hitel.net
211.41.82.192	A	mail16.paran.com
211.41.82.192	A	mail16.hanmir.com
211.41.82.193	PTR	mail17.hanmir.com
211.41.82.193	PTR	mail17.kttown.com
211.41.82.193	PTR	mail17.paran.com
211.41.82.194	PTR	mail18.hanmir.com
211.41.82.194	PTR	mail18.kttown.com
211.41.82.194	PTR	mail18.paran.com
211.41.82.195	PTR	mail19.hanmir.com
211.41.82.195	PTR	mail19.kttown.com
211.41.82.195	PTR	mail19.paran.com
211.41.82.224	A	mail2.magicn.com
211.41.82.224	A	mail2.show.co.kr
211.41.82.225	A+PTR	mail3.magicn.com
211.41.82.225	A+PTR	mail3.show.co.kr
211.41.83.136	A	dailynews.hitel.net
211.41.83.228	A	comic.hanmir.com
211.41.84.12	A	cdns2.hitel.net
211.41.84.13	A	cdns3.hitel.net
211.41.84.182	A	rmail7.paran.com
211.41.84.183	A	rmail8.paran.com
211.41.84.184	A	rmail9.paran.com
211.41.84.193	PTR	mailex01.paran.com
211.41.85.29	PTR	sni07.paran.com
211.41.85.29	PTR	sni07.hitel.net
211.41.85.197	PTR	smtp.paran.com
211.41.85.197	PTR	smtp.hitel.net
211.41.87.99	A	home.hitel.net
211.41.87.136	A	biz.hitel.net
211.41.87.136	A	alzip.hitel.net