Node types and capabilities v5.6

A PGD cluster can contain several different types of node, each with its own role. This section describes the different types of node that can be configured in a PGD cluster.

  • Overview is an overview the kinds of node that can exist in PGD clusters and their associated roles.

  • Witness nodes looks at the witness node, a special class of PGD node, dedicated to establishing consensus in a group.

  • Logical standby nodes shows how to efficiently keep a node on standby synchronized and ready to step in as a primary in the case of failure.

  • Subscriber-only nodes and groups looks at how subscriber-only nodes work with subscriber-only groups, how they boost read scalability and the different options for configuring them.

Overview

An overview of the different types of nodes that can be configured and grouped in a PGD cluster

Witness

Used to enable consensus in PGD clusters, both within clusters and outside regions

Logical standby

Used to keeping nodes ready to step up as a primary in case of failure

Subscriber-only

Used to build out read scalability by allowing groups of read-only nodes in a PGD cluster.