Error
Error Code:
79
MongoDB Error 79: Unknown Write Concern
Description
Error 79, 'Unknown Repl Write Concern,' indicates that MongoDB's replica set cannot understand or fulfill the write concern specified for a write operation. This usually happens when the write concern is malformed, refers to non-existent replica set members/tags, or is incompatible with the current replica set configuration.
Error Message
Unknown Repl Write Concern
Known Causes
3 known causesInvalid Write Concern Syntax
The write concern provided by the client application contains a syntax error, an invalid value, or refers to a non-existent parameter.
Mismatched Replica Set Tags
The custom write concern specifies tags (e.g., `'{ "tag": "value" }'`) that do not exist or are incorrectly applied to the replica set members.
Outdated Replica Set Configuration
The write concern relies on a replica set configuration (e.g., number of members, tag sets) that has changed since the application was last updated.
Solutions
Coming SoonDetailed step-by-step solutions for this error are being prepared. In the meantime, try these general troubleshooting tips:
General Troubleshooting Tips
- Check the error message carefully for specific details
- Review recent changes that might have caused the error
- Search for the exact error code in the official documentation
- Check log files for additional context
- Try restarting the application or service