Robtex

Up: 210.0.248.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 210.0.252.0/23
Down right: 210.0.254.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
210.0.254.1	PTR	a210-0-254-1.deploy.akamaitechnologies.com
210.0.255.65	A+PTR	nms65.hgc.com.hk
210.0.255.76	PTR	mail.waibo.com.hk
210.0.255.117	PTR	spectrum.hgc.com.hk
210.0.255.122	PTR	nms-dia.hgc.com.hk
210.0.255.124	A+PTR	nms04.hgc.com.hk
210.0.255.130	PTR	efax.on-nets.com
210.0.255.130	A	efax01.hgc.com.hk
210.0.255.133	A	relayip.on-nets.com
210.0.255.134	A+PTR	smtpip01.on-nets.com
210.0.255.134	A	lbel.com.hk
210.0.255.137	A+PTR	smtp02.on-nets.com
210.0.255.137	A	lbel.com.hk
210.0.255.137	A	safetygodown.com.hk
210.0.255.141	A	smtpip01.hgcbroadband.com
210.0.255.141	A	smtpip01.net-yan.com
210.0.255.141	A	smtpip01.threebb.com.hk
210.0.255.146	A	my.threebb.com.hk
210.0.255.146	A	my.hgcbroadband.com
210.0.255.148	A+PTR	efax.hgcbroadband.com
210.0.255.150	A	relayip.on-nets.com
210.0.255.152	A	mail.3gmail.hk
210.0.255.152	A	smtpip02.hgcbroadband.com
210.0.255.152	A	smtpip02.threebb.com.hk
210.0.255.153	A	relay.on-nets.com
210.0.255.154	PTR	relay.on-nets.com
210.0.255.157	A+PTR	smtp02.hgcbroadband.com
210.0.255.157	A	mail.net-yan.com
210.0.255.157	A	smtp02.net-yan.com
210.0.255.160	A	skype.threebb.com.hk
210.0.255.160	A	hgcbroadband.com
210.0.255.160	A	www.hgcbroadband.com
210.0.255.161	PTR	smtpip02.on-nets.com
210.0.255.161	A	safetygodown.com.hk
210.0.255.161	A	fagps.edu.hk
210.0.255.164	PTR	smtp04.on-nets.com
210.0.255.164	A+PTR	smtp04b.on-nets.com
210.0.255.164	A	lbel.com.hk
210.0.255.165	PTR	hidcsvrdns.hgc.com.hk
210.0.255.167	A	relay.on-nets.com
210.0.255.170	A+PTR	relay.on-nets.com
210.0.255.170	A	hgcbackup.scmedia.com.hk
210.0.255.174	A	mgw.hutchcity.com
210.0.255.175	A	mail02.hgcbroadband.com
210.0.255.175	A	mail02.threebb.com.hk
210.0.255.176	A+PTR	smtp.3gmail.hk
210.0.255.180	A	pf01.hutchcity.com
210.0.255.181	A	smtpip01.hutchcity.com
210.0.255.184	A+PTR	ddns01.net-yan.com
210.0.255.185	A	ldap07.net-yan.com
210.0.255.190	A	mgw.net-yan.com
210.0.255.191	A	efaxinbound.on-nets.com
210.0.255.192	A	metronet.hgc.com.hk
210.0.255.195	A	ddns02.net-yan.com
210.0.255.208	A+PTR	ldap03.net-yan.com
210.0.255.209	A+PTR	news.hgc.com.hk
210.0.255.209	A	news.hgcbroadband.com
210.0.255.210	PTR	smtp01.net-yan.com
210.0.255.210	A	smtp01.hgcbroadband.com
210.0.255.211	PTR	web.on-nets.com
210.0.255.215	A	greetings.hgcbroadband.com
210.0.255.216	PTR	rbsdns35.net-yan.com
210.0.255.219	A+PTR	harelay.on-nets.com
210.0.255.220	A	smtpip02.hutchcity.com
210.0.255.223	A+PTR	hidcsvrdns.hgc.com.hk
210.0.255.224	A	relay.on-nets.com
210.0.255.224	A	hgcbackup.scmedia.com.hk
210.0.255.225	A	notify.blackberry.on-nets.com
210.0.255.225	A	mail.blackberry.on-nets.com
210.0.255.226	PTR	rbsdns33.net-yan.com
210.0.255.228	A+PTR	bbdns3.on-nets.com
210.0.255.229	A+PTR	harelay.on-nets.com
210.0.255.230	A	relayip.on-nets.com
210.0.255.231	A	relayip.on-nets.com
210.0.255.233	A	promo.hgc.com.hk
210.0.255.233	A	web.on-nets.com
210.0.255.233	A	on-nets.com
210.0.255.236	A	webmail01.on-nets.com
210.0.255.237	A	db01.net-yan.com
210.0.255.238	A	password.hgcbroadband.com
210.0.255.238	A	admin.hgcbroadband.com
210.0.255.241	A	tucows.hgcbroadband.com
210.0.255.241	A	hgc.tucows.com
210.0.255.242	A+PTR	inbound.on-nets.com
210.0.255.243	A+PTR	ldap02.net-yan.com
210.0.255.245	PTR	rbsdns34.net-yan.com
210.0.255.248	A	ldap01.net-yan.com
210.0.255.250	PTR	bbdns1.on-nets.com
210.0.255.250	A	www.cibc.com.hk
210.0.255.250	A	cibc.com.hk
210.0.255.251	PTR	bbdns2.on-nets.com