gRPC 9 FAILED_PRECONDITION vs 14 UNAVAILABLE
Both gRPC 9 (FAILED_PRECONDITION) and 14 (UNAVAILABLE) belong to the gRPC Status Codes category. 9 indicates that the operation was rejected because the system is not in a state required for the operation's execution. For example, deleting a non-empty directory. Meanwhile, 14 means that the service is currently unavailable. This is most likely a transient condition, which can be corrected by retrying with a backoff.
描述
The operation was rejected because the system is not in a state required for the operation's execution. For example, deleting a non-empty directory.
何时出现
The request is valid on its own, but the system's current state doesn't allow it — like trying to delete a non-empty directory or update a resource that has been modified concurrently.
如何修复
Bring the system into the required state before retrying. For example, empty the directory first, or re-read the resource to get the latest version before updating.
描述
The service is currently unavailable. This is most likely a transient condition, which can be corrected by retrying with a backoff.
何时出现
The server is overloaded, shutting down, or a network partition occurred. This is the most common code to retry on, as it's explicitly transient.
如何修复
Retry with exponential backoff. If persistent, check the server health, load balancer configuration, and network connectivity between client and server.
主要区别
gRPC 9: The operation was rejected because the system is not in a state required for the operation's execution. For example, deleting a non-empty directory.
gRPC 14: The service is currently unavailable. This is most likely a transient condition, which can be corrected by retrying with a backoff.
You encounter 9 when the request is valid on its own, but the system's current state doesn't allow it — like trying to delete a non-empty directory or update a resource that has been modified concurrently.
You encounter 14 when the server is overloaded, shutting down, or a network partition occurred. This is the most common code to retry on, as it's explicitly transient.
何时使用哪个
For 9 (FAILED_PRECONDITION): Bring the system into the required state before retrying. For example, empty the directory first, or re-read the resource to get the latest version before updating. For 14 (UNAVAILABLE): Retry with exponential backoff. If persistent, check the server health, load balancer configuration, and network connectivity between client and server.