Robtex

Up: 208.87.136.0/21
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Down left: 208.87.136.0/23
Down right: 208.87.138.0/23

IP	Type	Hostname
208.87.136.138	A	backupmailrr.dbsintl.com
208.87.136.139	PTR	sv4-mta-55a-rx.emailfiltering.com
208.87.136.142	PTR	sv4-mta-58a-rx.us.emailfiltering.com
208.87.136.143	A	strategicinfusion.com.w2.mx-route.com
208.87.136.145	PTR	sv4-mta-61a-rx.us.emailfiltering.com
208.87.136.157	A	ns2.fdbdns.com
208.87.136.232	PTR	sv4-mta-51a.emailfiltering.com
208.87.136.235	PTR	sv4-mta-54a.emailfiltering.com
208.87.136.238	PTR	sv4-mta-56a.emailfiltering.com
208.87.136.239	PTR	sv4-mta-57a.emailfiltering.com
208.87.136.240	PTR	sv4-mta-58a.us.emailfiltering.com
208.87.136.242	PTR	sv4-mta-60a.us.emailfiltering.com
208.87.136.243	PTR	sv4-mta-61a.us.emailfiltering.com
208.87.136.248	A	outbound6.webroot.com
208.87.137.59	PTR	outbound5.webroot.com
208.87.137.60	PTR	products.webroot.com
208.87.137.68	PTR	enterprise.webroot.com
208.87.137.68	A	enterprise.webroot.akadns.net
208.87.137.139	PTR	sv4-mta-55b-rx.emailfiltering.com
208.87.137.140	PTR	sv4-mta-56b-rx.emailfiltering.com
208.87.137.142	PTR	sv4-mta-58b-rx.us.emailfiltering.com
208.87.137.143	A	desirestreet.org.w1.mx-route.com
208.87.137.143	A	primeresource.w1.mx-route.com
208.87.137.145	PTR	sv4-mta-61b-rx.us.emailfiltering.com
208.87.137.156	A+PTR	weblogin-us.webroot.com
208.87.137.157	A	ns4.fdbdns.com
208.87.137.168	A+PTR	crawler.webroot.com
208.87.137.170	PTR	test.us.wrproxy.com
208.87.137.170	A	proxy.flower-mound.com
208.87.137.170	A	wwss.wrproxy.webrootdns.net
208.87.137.230	PTR	sv4-mds-01.us.emailfiltering.com
208.87.137.233	PTR	sv4-mta-52b.emailfiltering.com
208.87.137.234	PTR	sv4-mta-53b.emailfiltering.com
208.87.137.235	PTR	sv4-mta-54b.emailfiltering.com
208.87.137.236	A+PTR	smtp-ca.webroot.com
208.87.137.237	PTR	sv4-mta-55b.emailfiltering.com
208.87.137.238	PTR	sv4-mta-56b.emailfiltering.com
208.87.137.239	PTR	sv4-mta-57b.emailfiltering.com
208.87.137.240	PTR	sv4-mta-58b.us.emailfiltering.com
208.87.137.241	PTR	sv4-mta-59b.us.emailfiltering.com
208.87.137.242	PTR	sv4-mta-60b.us.emailfiltering.com
208.87.137.243	PTR	sv4-mta-61b.us.emailfiltering.com
208.87.139.131	A+PTR	ns3.webroot.com
208.87.139.131	A	ns3.wrdns.net
208.87.139.132	A	mobile.webroot.webrootdns.net
208.87.139.132	A	mobile.webroot.com
208.87.139.137	A	enterprise.webroot.com
208.87.139.141	A	products.webroot.webrootdns.net
208.87.139.142	A	sales.webroot.com
208.87.139.144	A	updates.webroot.com
208.87.139.144	A	defs.webroot.com
208.87.139.144	A	updates.webroot.webrootdns.net
208.87.139.148	A	vector.brightcloud.com
208.87.139.156	PTR	outbound3.webroot.com
208.87.139.156	A	smtp-ca.webroot.com