Robtex

Up: 8.20.240.0/23
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Down left: 8.20.241.0/25
Down right: 8.20.241.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
8.20.241.1	A+PTR	ns1.nudns.com
8.20.241.1	A	securedns1.webhosting4u.gr
8.20.241.1	A	anycast1.topdns.com
8.20.241.2	PTR	ns3.nudns.com
8.20.241.2	A	ns3.leftofthedot.com
8.20.241.2	A	anycast3.topdns.com
8.20.241.3	PTR	ns1.dnsbycomodo.net
8.20.241.5	A+PTR	ns1.elv8.net
8.20.241.6	A+PTR	ns3.elv8.net
8.20.241.12	PTR	dns5.registrar-servers.com
8.20.241.16	PTR	ns5.101domain.com
8.20.241.16	A	ns6.101domain.com
8.20.241.17	PTR	ns7.101domain.com
8.20.241.17	A	ns8.101domain.com
8.20.241.25	A	dns3.brandshelter.info
8.20.241.26	PTR	msns1.vilayer.com
8.20.241.27	A+PTR	ans4.brandshelter.net
8.20.241.30	PTR	ns1.leftofthedot.com
8.20.241.31	PTR	ns3.leftofthedot.com
8.20.241.35	PTR	ns1.dgtldns.com
8.20.241.50	PTR	ns1.ssl-processing.com
8.20.241.60	PTR	ns2.monroehosting.com
8.20.241.61	A+PTR	ns1.4thenet.net
8.20.241.62	A+PTR	ns3.4thenet.net
8.20.241.69	A+PTR	ns1.dns.com.sv
8.20.241.69	A	ns1.dns.gob.sv
8.20.241.69	A	dns1.wevdns.net
8.20.241.70	A+PTR	ns3.dns.com.sv
8.20.241.70	A	ns3.dns.gob.sv
8.20.241.70	A	dns3.wevdns.com
8.20.241.71	A	ns100.adwebtech.com
8.20.241.72	A	ns300.adwebtech.com
8.20.241.73	PTR	ns1.perfectaddress.com
8.20.241.74	PTR	ns3.perfectaddress.com
8.20.241.79	PTR	ns1.crain.com
8.20.241.81	PTR	ns1.dnsstation.com
8.20.241.83	PTR	ns1.domain.jobs
8.20.241.84	PTR	ns3.domain.jobs
8.20.241.85	PTR	ns1.retailup.com
8.20.241.86	PTR	ns3.retailup.com
8.20.241.91	PTR	ns1.flamingdns.co.uk
8.20.241.91	A	ns1.bankads.com
8.20.241.92	PTR	ns3.flamingdns.co.uk
8.20.241.92	A	ns3.bankads.com
8.20.241.95	A	ns1.edcogroup.net
8.20.241.99	A+PTR	ns1.subhostingdns.com
8.20.241.100	A+PTR	ns3.subhostingdns.com
8.20.241.105	A+PTR	premium-ns1.dnsowl.com
8.20.241.106	A+PTR	ns-a.eurodns.com
8.20.241.107	A+PTR	ns1.eurodns.com
8.20.241.108	A+PTR	ns3.eurodns.com
8.20.241.110	A	ns3.ebrandservices.com
8.20.241.113	A	ns1.prodns.net
8.20.241.114	A	ns3.prodns.net
8.20.241.150	A+PTR	premium-ns3.dnsowl.com