Consensus method and apparatus, and blockchain system

A consensus method performed by a first backup node in a blockchain system, the blockchain system further comprising a primary node, the method comprising:

• receiving a transaction hash list broadcast by the primary node, wherein the transaction hash list comprising a hash value of at least one unverified transaction;
• searching for the at least one unverified transaction based on the transaction hash list;
• verifying the at least one unverified transaction to obtain a first verification result;
• obtaining a first hash value based on the at least one unverified transaction;
• saving a corresponding relationship between the first verification result and the first hash value;
• receiving a pre-preparation message broadcast by the primary node, wherein the pre-preparation message comprising a second verification result obtained by verifying the at least one unverified transaction by the primary node and a second hash value obtained based on the at least one unverified transaction;
• searching for the first verification result corresponding to the second hash value in the pre-preparation message based on the corresponding relationship;
• broadcasting a preparation message in the blockchain system based on determining that the searched first verification result is the same as the second verification result, wherein the preparation message is used for consensus processing by the primary node and at least one backup node in the blockchain system;
• and
• wherein the blockchain system further comprises second backup nodes, the second backup nodes are different from the first backup node, the method further comprises:
• based on determining that the first backup node fails to find the at least one unverified transaction based on the transaction hash list, requesting the at least one unverified transaction from the primary node or any one of the second backup nodes.

A blockchain system, comprising a primary node and a first backup node, the first backup node being any backup node in the blockchain system, wherein

• the primary node is configured to broadcast a transaction hash list in the blockchain system, the transaction hash list comprising a hash value of at least one unverified transaction;
• the first backup node is configured to receive the transaction hash list, to search for the at least one unverified transaction based on the transaction hash list, to verify the at least one unverified transaction to obtain a first verification result, to obtain a first hash value based on the at least one unverified transaction, and to save a corresponding relationship between the first verification result and the first hash value;
• the primary node is further configured to search for the at least one unverified transaction based on the transaction hash list, to verify the at least one unverified transaction to obtain a second verification result, to obtain a second hash value based on the at least one unverified transaction, and to broadcast a pre-preparation message carrying the second verification result and the second hash value in the blockchain system;
• and
• the first backup node is further configured to receive the pre-preparation message, to search for the first verification result corresponding to the second hash value based on the corresponding relationship, and to broadcast a preparation message in the blockchain system based on determining that the searched first verification result is the same as the second verification result, the preparation message is used for consensus processing by the primary node and at least one backup node in the blockchain system,
• wherein before broadcasting the transaction hash list in the blockchain system, the primary node is further configured to determine whether a current network state of the blockchain system meets preset conditions, and trigger the broadcasting the transaction hash list in the blockchain system based on determining that the current network state meets preset conditions.