Robtex

Up: 170.138.104.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 170.138.104.0/23
Down right: 170.138.106.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
170.138.104.8	A+PTR	vpnportal.emdeon.com
170.138.104.8	PTR	z-bnacp-ivp-05.emdeon.com
170.138.104.25	PTR	mxrelay02.emdeon.com
170.138.104.25	A	mxrelay02.webmd.net
170.138.104.49	A	emdeoncareers.com
170.138.104.49	A	emdeoncareers.net
170.138.104.49	A	webmdcareers.net
170.138.104.161	A+PTR	exchange.dakotaimaging.com
170.138.104.163	A+PTR	support.dakotaimaging.com
170.138.104.167	A	smtpin.dakotaimaging.com
170.138.104.192	A+PTR	dp.emdeon.com
170.138.104.193	PTR	pl-mxrelay04.emdeon.com
170.138.104.195	A+PTR	securelink.emdeon.com
170.138.104.203	A+PTR	dcomm.emdeon.com
170.138.104.241	A+PTR	zbnaaeexpedge01p01.changehealthcare.com
170.138.105.38	A	ns3.kuhjqyx.com
170.138.105.38	A	ns1.kuhjqyx.com
170.138.105.38	A	kuhjqyx.com