The present disclosure discloses a distributed system and a message processing method. The distributed system includes a client and a plurality of nodes. The client includes processing circuitry that is configured to send a message including a digital signature of the client. The distributed system is in a first consensus mode for reaching a consensus on the message. The processing circuitry obtains results from a subset of the nodes that receive the message. The results have respective digital signatures of the subset of the nodes. After verifying the digital signatures of the subset of the nodes, the processing circuitry of the client determines, based on the results, whether one or more of the nodes in the distributed system is malfunctioned.