Middleware

Galera Cluster

How Galera Cluster connects to the rest of the stack: what it depends on, what depends on it, and what it is commonly deployed alongside.

Concepts it implements

A majority of members must agree before a decision stands, which is what stops two halves of a partitioned cluster both acting as leader.

Two nodes both believe they are primary, usually after a network partition, and both accept writes that cannot afterwards be reconciled.

How this component relates to the rest of the stack. Items without a link are not covered here yet.

Must be present for this to run

Commonly run alongside

Solves a similar problem differently