EDB Postgres Distributed v3.7
EDB Postgres Distributed provides multi-master replication and data distribution with advanced conflict management, data-loss protection, and throughput up to 5X faster than native logical replication, and enables distributed PostgreSQL clusters with high availability up to five 9s.
By default EDB Postgres Distributed uses asynchronous replication, applying changes on the peer nodes only after the local commit. Additional levels of synchronicity can be configured between different nodes, groups of nodes or all nodes.
EDB Postgres Distributed consists of several components that make the whole cluster work.
Postgres server
Three different Postgres distributions can be used:
- PostgreSQL - open source
- EDB Postgres Extended Server - Postgres compatible and optimized for replication (formerly known as 2nd Quadrant Postgres)
- EDB Postgres Advanced Server - Postgres or Oracle compatible, optimized for replication, and additional enterprise features
What Postgres distribution and version is right for you depends on the features you need. See Postgres-specific features for detailed information.
BDR extension
A Postgres server with the BDR extension installed is referred to as a BDR node. BDR nodes can be either data nodes or witness nodes.
Witness nodes don't participate in data replication and are only used as a tie-breaker for consensus.
pglogical3 extension
BDR depends on pglogical 3.7 to provide the replication channel upon which BDR builds.
HARP
HARP is connection management tool for a EDB Postgres Distributed cluster.
It leverages consensus-driven quorum to determine the correct connection end-point in a semi-exclusive manner to prevent unintended multi-node writes from an application. This reduces the potential for data conflicts.
Compatibility matrix
EDB Postgres Distributed | BDR Extension | pgLogical3 Extension | HARP | Commmunity PostgreSQL | EDB Postgres Extended Server | EDB Postgres Advanced Server | PGD CLI |
---|---|---|---|---|---|---|---|
4 | 4 | n/a | 2 | 12, 13, 14 | 12, 13, 14 | 12, 13, 14 | 1 |
3.7 | 3.7 | 3.7 | 2 | 11, 12, 13 | 11r2, 12, 13 | 11, 12, 13 | n/a |
3.6 | 3.6 | 3.6 | 2 | 10, 11 | 11r1 | n/a | n/a |