Robtex

Up: 158.72.128.0/18
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Down left: 158.72.128.0/20
Down right: 158.72.144.0/20

IP	Type	Hostname
158.72.139.19	A+PTR	smtp.ees.hhs.gov
158.72.139.19	A	smtp.hhs.gov
158.72.139.20	PTR	owa.hhs.gov
158.72.139.23	A	autodiscover.hhs.gov
158.72.139.58	A+PTR	smtp01.ees.hhs.gov
158.72.139.59	A+PTR	smtp02.ees.hhs.gov
158.72.147.27	A	rates.psc.gov