DNS response code NOERROR
Essentially, it means the DNS query got a valid response. It's a way of saying everything was OK, there were no issues with the query. A user asked to go bluecatnetworks.com, and the resolver and DNS servers took it there.
What does Rcode mean?
A DNS response header has an RCODE (Response Code) field, used for indicating errors, and status bits that indicate whether an answer is authoritative and/or authentic.
What causes DNS ServFail?
DNS record lookups can fail for a number of reasons, the most common of which is due what's called a “ServFail” error. ServFail errors occur when there's an error communicating with a DNS server. This could have a number of causes, including an error on the DNS server itself, or a temporary networking issue.
