Robtex

Up: 208.73.144.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 208.73.144.0/23
Down right: 208.73.146.0/23

IP	Type	Hostname
208.73.144.71	A	prod2.voipdnsservers.com
208.73.144.71	A	prod.voipdnsservers.com
208.73.144.71	A	prod1.voipdnsservers.com
208.73.144.74	A	bt.voipdnsservers.com
208.73.144.75	A	pai.voipdnsservers.com
208.73.144.171	A	pnx1.voipdnsservers.com
208.73.144.181	A	phx02.voipdnsservers.com
208.73.144.181	A	phx01.voipdnsservers.com
208.73.145.50	A	cp4.nextiva.com
208.73.145.50	A	cp.nextiva.com
208.73.145.50	A	cpeast.nextiva.com
208.73.145.51	A	dm.nextiva.com
208.73.145.54	A	east.nextiva.im
208.73.145.54	A	ums1s4.east.nextiva.im
208.73.145.71	A	chi2.voipdnsservers.com
208.73.145.71	A	chi1.voipdnsservers.com
208.73.145.80	A	chi3.voipdnsservers.com
208.73.145.187	A	cp24.nextiva.com
208.73.146.93	A	trunking.voipdnsservers.com
208.73.146.95	A	sbc.voipdnsservers.com
208.73.146.95	A	c01-sbc.voipdnsservers.com
208.73.146.95	A	voipdnsservers.com
208.73.147.62	A	ums1s1.nextiva.im
208.73.147.62	A	nextiva.im
208.73.147.74	A	nextivachat.com
208.73.147.142	A	palladion3.nextiva.com
208.73.147.143	A	analytics.nextiva.com
208.73.147.150	A	voicemail.nextiva.com
208.73.147.201	A	np3.nextiva.com
208.73.147.211	A	admin.nextiva.com
208.73.147.211	A	salestracker.nextiva.com
208.73.147.217	A	nextos.com