Robtex

Up: 168.181.16.0/21
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Down left: 168.181.20.0/23
Down right: 168.181.22.0/23

IP	Type	Hostname
168.181.22.12	PTR	12.22.in.opencdn.nic.br
168.181.22.12	A	r1.sn-pmcg-nn5e.googlevideo.com
168.181.22.13	PTR	13.22.in.opencdn.nic.br
168.181.22.13	A	r2.sn-pmcg-nn5e.googlevideo.com
168.181.22.14	PTR	14.22.in.opencdn.nic.br
168.181.22.14	A	r3.sn-pmcg-nn5e.googlevideo.com
168.181.22.15	PTR	15.22.in.opencdn.nic.br
168.181.22.15	A	r4.sn-pmcg-nn5e.googlevideo.com