DNS 9 NOTAUTH vs 20 BADNAME
Both DNS 9 (NOTAUTH) and 20 (BADNAME) belong to the DNS Response Codes (RCODEs) category. 9 indicates that server Not Authoritative for zone, or Not Authorized. The server is not authoritative for the zone named in the Zone section. Meanwhile, 20 means that duplicate key name. The key name in a TKEY negotiation is already in use or conflicts with an existing key.
Description
Server Not Authoritative for zone, or Not Authorized. The server is not authoritative for the zone named in the Zone section.
When You See It
You sent a dynamic update or zone operation to a server that is not the authoritative master for that zone, or the server rejected it due to TSIG authentication failure.
How to Fix
Send the update to the correct primary authoritative server for the zone. If using TSIG, verify the key name and secret match on both client and server.
Description
Duplicate key name. The key name in a TKEY negotiation is already in use or conflicts with an existing key.
When You See It
A TKEY key establishment failed because a key with the same name already exists on the server from a previous session that was not properly cleaned up.
How to Fix
Use a unique key name for each TKEY session (e.g., append a timestamp or random suffix). Delete stale keys on the server if they are no longer needed.
Key Differences
DNS 9: Server Not Authoritative for zone, or Not Authorized. The server is not authoritative for the zone named in the Zone section.
DNS 20: Duplicate key name. The key name in a TKEY negotiation is already in use or conflicts with an existing key.
You encounter 9 when you sent a dynamic update or zone operation to a server that is not the authoritative master for that zone, or the server rejected it due to TSIG authentication failure.
You encounter 20 when a TKEY key establishment failed because a key with the same name already exists on the server from a previous session that was not properly cleaned up.
When to Use Which
For 9 (NOTAUTH): Send the update to the correct primary authoritative server for the zone. If using TSIG, verify the key name and secret match on both client and server. For 20 (BADNAME): Use a unique key name for each TKEY session (e.g., append a timestamp or random suffix). Delete stale keys on the server if they are no longer needed.