Robtex

Up: 217.30.88.0/21
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Down left: 217.30.88.0/23
Down right: 217.30.90.0/23

IP	Type	Hostname
217.30.88.4	A	tuvalu.verisign.com
217.30.89.48	PTR	epp.verisign-grs.com
217.30.89.79	A	ftp.rs.verisigndns.com
217.30.89.110	PTR	nsmanager.verisign-grs.com
217.30.89.152	PTR	epp.verisign-grs.com
217.30.90.100	A	domainscope.com