# Replication Protocol - [1-Binlog Events](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/1-binlog-events.md): This section provides an overview of the various events recorded in the binary log, which are the core units of replication data transmission. - [2-Binlog Event Header](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/2-binlog-event-header.md): Every binary log event starts with a standardized header containing metadata such as the timestamp, event type, server ID, and event size. - [3-Binlog Network Stream](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/3-binlog-network-stream.md): Describes the continuous packet stream format used to transmit binary log events from the primary server to the replica over the network. - [4-Semi-Sync Replication](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/4-semi-sync-replication.md): Explains the handshake and acknowledgement process for semi-synchronous replication, ensuring data is committed on at least one replica. - [5-Replica Registration](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/5-replica-registration.md): Details the initialization phase where a replica connects to the primary, authenticates, sends capabilities, and registers for updates. - [ANNOTATE\_ROWS\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/annotate_rows_event.md): This event accompanies row-based events to provide the original SQL query text, which is useful for auditing and debugging replication. - [BEGIN\_LOAD\_QUERY\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/begin_load_query_event.md): Used during LOAD DATA INFILE operations, this event marks the beginning of the data load and contains the initial query information. - [BINLOG\_CHECKPOINT\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/binlog_checkpoint_event.md): A marker event indicating a checkpoint in the binary log, used to ensure consistency and safe rotation of log files. - [COM\_BINLOG\_DUMP](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/com_binlog_dump.md): This command is sent by a replica to the primary server to request the start of the binary log event stream from a specific file and position. - [COM\_REGISTER\_SLAVE](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/com_register_slave.md): This command is used by a replica to register its details, such as server ID, hostname, and port, with the primary server. - [EXECUTE\_LOAD\_QUERY\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/execute_load_query_event.md): This event is used for LOAD DATA INFILE operations, managing the execution phase similar to a QUERY\_EVENT but with extra static fields for file handling. - [Fake GTID\_LIST Event](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/fake-gtid_list-event.md): A synthetic event sent by the master after the initial handshake to inform the replica of its current GTID state, it is not written to the binary log. - [Fake ROTATE\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/fake-rotate_event.md): An artificial event sent to the replica to indicate the name of the binary log file on the master, ensuring the replica knows which file is being read. - [FORMAT\_DESCRIPTION\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/format_description_event.md): This descriptor event appears at the start of every binary log file, defining the server version, binlog version, and header lengths for all event types. - [GTID\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/gtid_event.md): The GTID\_EVENT marks the start of a new transaction event group, associating it with a Global Transaction ID (GTID) and providing commit flags. - [GTID\_LIST\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/gtid_list_event.md): Logged during binlog rotation or checkpoints, this event lists the GTIDs present in the binary log to help replicas determine their replication state. - [HEARTBEAT\_LOG\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/heartbeat_log_event.md): A heartbeat event sent over the network by the master when there are no binlog events, ensuring the replica knows the connection is still active. - [INTVAR\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/intvar_event.md): This event records integer values for auto-increment columns or the LAST\_INSERT\_ID function, ensuring that these values are replicated deterministically. - [QUERY\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/query_event.md): The QUERY\_EVENT records text-based SQL statements for statement-based replication, capturing the query string and execution context like the default database. - [RAND\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/rand_event.md): The RAND\_EVENT records the two seed values used for the random number generator, ensuring that calls to the RAND() function produce identical results on replicas. - [ROTATE\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/rotate_event.md): The ROTATE\_EVENT indicates a log rotation, specifying the name of the next binary log file and the position where writing will continue. - [ROWS\_EVENT\_V1/V2, ROWS\_COMPRESSED\_EVENT\_V1](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/rows_event_v1v2-rows_compressed_event_v1.md): These events record row-level changes (WRITE, UPDATE, DELETE) for replication, with versions supporting different column counts and compression. - [START\_ENCRYPTION\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/start_encryption_event.md): This event marks the beginning of encrypted data in the binary log, defining the encryption scheme and key version for subsequent events. - [STOP\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/stop_event.md): The STOP\_EVENT is written to the binary log when the server shuts down, serving as a marker for a clean stop. - [TABLE\_MAP\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/table_map_event.md): This event provides a mapping between a table ID and its table definition, preceding row events to interpret the row data correctly. - [USER\_VAR\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/user_var_event.md): The USER\_VAR\_EVENT logs the value of a user-defined variable, ensuring that statements using variables replicate consistently. - [XA\_PREPARE\_LOG\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/xa_prepare_log_event.md): This event records the preparation phase of an XA transaction, storing the XID to support two-phase commit and recovery. - [XID\_EVENT](https://mariadb.com/docs/server/reference/clientserver-protocol/replication-protocol/xid_event.md): The XID\_EVENT signifies the commit of a transaction, containing the transaction ID (XID) to ensure atomicity across replication. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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