Robtex

Up: 72.171.0.0/17
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Down left: 72.171.0.0/19
Down right: 72.171.32.0/19

IP	Type	Hostname
72.171.0.0	PTR	host721710000.direcway.com
72.171.0.1	PTR	host721710010.direcway.com
72.171.0.2	PTR	host721710020.direcway.com
72.171.1.2	PTR	host721710021.direcway.com
72.171.2.0	PTR	host721710002.direcway.com
72.171.4.0	PTR	host721710004.direcway.com
72.171.8.0	PTR	host721710008.direcway.com
72.171.8.2	PTR	host721710028.direcway.com
72.171.14.2	PTR	host7217100214.direcway.com
72.171.18.126	PTR	host721710012618.direcway.com
72.171.20.200	PTR	host721710020020.direcway.com
72.171.21.28	PTR	host72171002821.direcway.com
72.171.24.123	PTR	host721710012324.direcway.com
72.171.24.124	PTR	host721710012424.direcway.com
72.171.24.247	PTR	host721710024724.direcway.com
72.171.24.248	PTR	host721710024824.direcway.com
72.171.27.2	PTR	host7217100227.direcway.com
72.171.33.1	PTR	host7217100133.direcway.com
72.171.36.129	PTR	host721710012936.direcway.com
72.171.45.65	PTR	host72171006545.direcway.com
72.171.45.194	PTR	host721710019445.direcway.com
72.171.48.114	PTR	host721710011448.direcway.com
72.171.48.126	PTR	host721710012648.direcway.com
72.171.50.11	PTR	host72171001150.direcway.com