Aurora 24 keeps MySQL 524 's SQL layer and replaces the storage. Every instance in a cluster reads one shared cluster volume that keeps copies of the data in three Availability Zones and grows by itself (up to 256 TiB, depending on the engine version). Adding a reader copies no data, and a failover promotes a reader that already sees every page:
The same describe-db-engine-versions call with --engine aurora-mysql listedn8.0.mysql_aurora.3.13.0 and 8.4.mysql_aurora.8.4.8` as the newest versions: the prefix is the MySQL line. Aurora MySQL version 3 matches MySQL 8.0 (3.13 is 8.0.45) with standard support to 30 April 2028; Aurora MySQL 8.4 matches the 8.4 LTS. Neither runs 9.7. A reader endpoint spreads reads over up to 15 replicas. In us-east-1 on 23 September 2026 a db.t4g.medium cost USD 0.073 an hour, plus USD 0.10 per GB-month and 0.20 per million I/O requests; I/O-Optimized drops the I/O charge and pays off once I/O is 25% of the bill. Serverless v2 (USD 0.12 per ACU-hour) can pause at 0 ACUs from Aurora MySQL 3.08.0, but the next connection waits about 15 seconds: fine for staging, not for a shop.