DNS 7 YXRRSET vs 20 BADNAME
Both DNS 7 (YXRRSET) and 20 (BADNAME) belong to the DNS Response Codes (RCODEs) category. 7 indicates that rR Set Exists when it should not. A resource record set exists that the update prerequisite says should not. 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
RR Set Exists when it should not. A resource record set exists that the update prerequisite says should not.
When You See It
A DNS UPDATE failed because a specific RRset (e.g., an A record) already exists when the prerequisite required it to be absent.
How to Fix
Delete the conflicting RRset before retrying the update, or adjust your prerequisite conditions to match the actual zone state.
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 7: RR Set Exists when it should not. A resource record set exists that the update prerequisite says should not.
DNS 20: Duplicate key name. The key name in a TKEY negotiation is already in use or conflicts with an existing key.
You encounter 7 when a DNS UPDATE failed because a specific RRset (e.g., an A record) already exists when the prerequisite required it to be absent.
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 7 (YXRRSET): Delete the conflicting RRset before retrying the update, or adjust your prerequisite conditions to match the actual zone state. 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.