Exactly what is a method to handle database unavailability and redirect queries from not available slave to a different one out of Django 1.2?

Btw, i discovered, it was talked about: http://code.djangoproject.com/wiki/MultipleDatabaseSupport#Requirements (see "Transparently handling database failure")

UPD> I personally use PostgreSQL after sales (most likely uses pg pool as well as other potgres cluster) under linux

If you work with a PostgreSQL after sales and therefore are on the Linux/BSD etc. system, think about using pgpool: http://pgpool.projects.postgresql.org/ This utility handles the connections towards the DB server for you personally, which means you only connect with pgpool. No requirement for you to definitely implement anymore logic. Just connect with pgpool, to not PostgreSQL itself.

Regrettably, right now there is no method to make use of the DATABASE_ROUTERS feature to be able to handle an not available database, you will need to make use of an exterior tool as others have recommended.

Gleam proxy for MySQL, MySQL Proxy. You'd connect with the proxy, which proxy would understand how to handle failover. Within the situation of MySQL Proxy, it is made for failover, and so i expect so that it is both stable and knowing how to deal with failures:)