Robtex

Up: 191.36.176.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 191.36.180.0/23
Down right: 191.36.182.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
191.36.180.3	PTR	3-180.36.191.ultranetfibra.com.br
191.36.180.3	A	ultrafiberbrasil.com.br
191.36.180.3	A	www.ultrafiberbrasil.com.br
191.36.180.6	A	ns1.ultranetfibra.com.br
191.36.180.6	A	ns1.ultrafiberbrasil.com.br
191.36.180.10	PTR	10-180.36.191.ultranetfibra.com.br
191.36.180.10	A	mauaonline.com.br
191.36.180.10	A	aspectonet.net
191.36.180.34	PTR	34-180.36.191.ultranetfibra.com.br
191.36.180.34	A	ns2.ultranetfibra.com.br
191.36.183.218	PTR	218-183.36.191.ultranetfibra.com.br