Robtex

Up: 83.121.0.0/19
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Down left: 83.121.16.0/21
Down right: 83.121.24.0/21

IP	Type	Hostname
83.121.19.2	PTR	hosting121019002.as8665.net
83.121.19.33	PTR	d19-33.dip.axsp.de
83.121.19.51	PTR	d19-51.dip.axsp.de
83.121.19.144	PTR	d19-144.dip.axsp.de
83.121.19.161	PTR	d19-161.dip.axsp.de
83.121.19.211	PTR	d19-211.dip.axsp.de
83.121.19.243	PTR	d19-243.dip.axsp.de
83.121.21.0	PTR	d21-0.dip.axsp.de
83.121.21.241	PTR	d21-241.dip.axsp.de
83.121.27.190	PTR	too.stupid.to.configure.reverse.dns
83.121.30.33	PTR	d30-33.dip.axsp.de
83.121.30.145	PTR	d30-145.dip.axsp.de
83.121.31.193	PTR	too.stupid.to.configure.reverse.dns