Robtex

Up: 173.199.72.0/21
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Down left: 173.199.72.0/23
Down right: 173.199.74.0/23

IP	Type	Hostname
173.199.72.12	PTR	173.199.72.12.choopa.net
173.199.72.73	PTR	173.199.72.73.choopa.net
173.199.72.73	A	london1.uk.servers.ironforce.net
173.199.72.131	PTR	173.199.72.131.choopa.net
173.199.72.209	PTR	173.199.72.209.choopa.net
173.199.73.67	PTR	173.199.73.67.choopa.net