177.53.210-21.grnettelecom.com.br has no NS records.
NS records for this zone are defined at grnettelecom.com.br.
NS records for this zone are defined at grnettelecom.com.br.
Question and response
Question
dig 177.53.210-21.grnettelecom.com.br. NS
Answer
The response has no answer records.
Authority
grnettelecom.com.br. 1800 SOA lia.ns.cloudflare.com. dns.cloudflare.com. 2398895487 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0