Metadata Storage

A GreptimeDB cluster stores its metadata in an external system, which the Metasrv component reads and writes. The supported backends are:

• etcd — a distributed key-value store with a small operational footprint.
• MySQL and PostgreSQL — relational databases with ACID transactions, replication, and established backup tooling. Both are available as managed services (RDS) on the major cloud platforms.

Which to choose

For development and testing, etcd is sufficient.

For production, use a cloud provider's managed relational database. A managed service covers high availability, automated backups, and maintenance, which is where most of the operational cost of self-hosting a metadata store goes.

Whichever backend you run, it sits outside GreptimeDB's own data path: it needs its own backup schedule and its own health monitoring.

Next steps

• Configuration — pointing Metasrv at a backend.
• Manage etcd — running etcd for development and testing.