Robtex

Up: 158.81.128.0/17
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Down left: 158.81.128.0/19
Down right: 158.81.160.0/19

IP	Type	Hostname
158.81.128.25	A	mxgate2.reliant.com
158.81.128.25	A	mxgate2.genon.com
158.81.128.117	A	drirs.reliant.com
158.81.128.124	A	compass.genon.com
158.81.129.31	PTR	reliant.com
158.81.130.13	A	mail1.genon.com
158.81.150.1	PTR	150-1.rrienergy.com
158.81.150.3	PTR	150-1.rrienergy.com
158.81.150.131	PTR	150-1.rrienergy.com
158.81.150.133	PTR	150-1.rrienergy.com
158.81.150.134	PTR	150-1.rrienergy.com
158.81.150.245	PTR	150-1.rrienergy.com
158.81.160.21	A	ftp.reliant.com
158.81.160.25	A	mxgate1.reliant.com
158.81.160.100	PTR	ads.reliantenergy.com
158.81.161.11	PTR	ns2.genon.com
158.81.161.20	A	mail2.genon.com
158.81.161.25	A	mxgate3.reliant.com
158.81.191.1	A+PTR	191-1.genon.com