Robtex

Up: 173.228.156.0/22
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Down left: 173.228.156.0/24
Down right: 173.228.157.0/24
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
173.228.156.221	PTR	youkgn-gle-221.youngcareerangle.com
173.228.157.12	A+PTR	ns20.pobox.com
173.228.157.12	A	ns1.rightbox.com
173.228.157.13	A+PTR	ns21.pobox.com
173.228.157.13	A	ns2.rightbox.com
173.228.157.29	A	listbox.com
173.228.157.29	A	www.listbox.com
173.228.157.39	PTR	pb-mx20.pobox.com
173.228.157.39	A	mx2.rightbox.com
173.228.157.39	A	mx5.rightbox.com
173.228.157.40	PTR	pb-mx21.pobox.com
173.228.157.40	A	mx2.rightbox.com
173.228.157.40	A	mx5.rightbox.com
173.228.157.41	PTR	pb-mx22.pobox.com
173.228.157.41	A	mx2.rightbox.com
173.228.157.41	A	mx5.rightbox.com
173.228.157.42	A+PTR	pb-mx23.pobox.com
173.228.157.42	A	mx2.rightbox.com
173.228.157.42	A	mx5.rightbox.com
173.228.157.52	A	smtp.pobox.com
173.228.157.52	A	pb-smtp20.pobox.com
173.228.157.53	A	smtp.pobox.com