Robtex

Up: 123.50.0.0/18
Can't show all results, try to descend to a more specific CIDR
Down left: 123.50.32.0/20
Down right: 123.50.48.0/20
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
123.50.33.254	A	123-50-33-254.3a.net.tw
123.50.36.29	PTR	5-top.net
123.50.36.221	PTR	illustrator-fly.com
123.50.36.240	PTR	inputoutput.com.tw
123.50.36.240	PTR	micon.com.tw
123.50.36.240	PTR	mail.inputoutput.com.tw
123.50.37.240	PTR	ns1.mishome.com.tw
123.50.38.240	PTR	myklim.net
123.50.41.116	PTR	mail.airlive.com
123.50.42.77	A	callsmq.com
123.50.42.236	PTR	xfiles.to
123.50.45.248	A+PTR	mail.nicebat.com.tw
123.50.45.248	A	luxurytravelleads.com
123.50.45.248	A	nicebat.com.tw
123.50.45.249	A+PTR	dns.nicebat.com.tw
123.50.47.182	A	789cycling.com
123.50.47.182	A	sunlightccfl.com
123.50.48.128	A	www.webkey.com.tw
123.50.48.129	A	copylock.net
123.50.49.87	PTR	mail.genepool.com.tw
123.50.49.171	A	appspot.com--vc.57883.net
123.50.49.171	A	www.m8ok.com
123.50.49.171	A	appspot.com--www.vv47.com
123.50.49.237	A	llinc.com.tw
123.50.49.251	PTR	mail.mariotoys.com.tw
123.50.51.210	PTR	dns.guild.com.tw
123.50.51.210	A	ns.chsweb.com.tw
123.50.51.210	A	mail.chsweb.com.tw
123.50.51.211	PTR	dns1.guild.com.tw
123.50.52.240	PTR	mail.omycar.com.tw
123.50.53.56	PTR	demoipcam.airlive.com
123.50.53.229	PTR	twweb7-clt.gocyberlink.com
123.50.53.231	PTR	twactivate-clt.gocyberlink.com
123.50.54.232	PTR	mail.omycar.com.tw
123.50.55.120	A	mail.hallmarkintl.com
123.50.55.249	A	www.amall.com.tw
123.50.56.41	PTR	officeog.com
123.50.56.205	A	angelcapital.cn
123.50.56.205	A	www.maohoo.com
123.50.56.205	A	maohoo.com
123.50.62.243	A	elvinyao.myqnapcloud.com
123.50.63.205	A	www.fatjohn.myds.me
123.50.63.205	A	fatjohn.myds.me