GTIDbased

GTIDbased refers to a method of database replication that uses Global Transaction Identifiers (GTIDs) to track and coordinate the execution of transactions across multiple servers. In GTID-based replication, every committed transaction is assigned a unique GTID, which is recorded in the server’s GTID set. This approach allows replicas to know precisely which transactions they have already applied and which are still needed, facilitating automated synchronization and promotion in failover scenarios.

How it works: When a transaction commits on a server, it receives a GTID that is added to that server’s GTID set. The binary log or its equivalent includes the GTID for each transaction. A replica reports its executed GTID set to the source, and the source sends only the missing transactions. As a result, replication can resume cleanly after interruptions and new replicas can be added with reduced manual configuration.

Benefits: GTID-based replication simplifies maintenance of large or complex replication topologies, enables easier automatic failover and slave promotion, and improves consistency by reducing drift between nodes. It also supports more straightforward point-in-time recovery and easier addition or removal of replicas.

Limitations and considerations: GTID gaps can occur and may require corrective actions. Enabling GTIDs requires careful configuration and testing, especially in mixed workloads or when upgrading systems. Data consistency before enabling GTID mode is important, and operations like purging GTIDs or handling multi-domain environments may introduce additional steps. Initial data synchronization across all nodes remains essential.

Implementation notes: In MySQL and MariaDB, enabling GTID-based replication typically involves setting options such as gtid_mode and enforce_gtid_consistency, ensuring all nodes share a consistent data state, and validating that backups and restores align with the GTID framework.