Database Replication Options

A number of options for replicating PostgreSQL databases exist. Some of the information below was obtained from a post by Chris Miles on the PostgreSQL forums (see http://archives.postgresql.org/pgsql-admin/2003-08/msg00300.php).

eRServer

Originally commercial, then apparently open-sourced. Development ceased and moved on to Slony-I.

PGReplication

Looks to be still very much in development, no mention of PostgreSQL v8.

PostgreSQL Replicator

"Store and forward" asynchronous data replication. No mention of support for PostgreSQL v8. Peer-to-peer (single master/slave pair) not multi-slave.

Slony-I

Probably the most complete implementation. Requires full-time network connectivity between database servers. Doesn't sound a good choice for more than about 12 servers, or for servers separated by a WAN.

Usogres

Very simple and not real-time replication. Free. Just duplication and only one master/slave pair.

"Lazy replication"

most dicussions about this talk about the system used by Musicbrainz, but an actual software package to do the job appears missing. Sounds like a method based on rsyncing databases dumps to remote read-only slaves - perfect for our task!

Based on this discussion it is proposed to implement our own version of "lazy replication". See DatabaseReplication.

-- SteveMarple - 16 Mar 2007