Node management v5.6

All data nodes in a PGD cluster are members of one or more groups. By default, all data nodes are members of the top-level group, which spans all data nodes in the PGD cluster. Nodes can also belong to subgroups that can be configured to reflect logical or geographical organization of the PGD cluster.

You can manage nodes and groups using the various options available with nodes and subgroups.

• Node types covers the kinds of node that can exist in PGD clusters.

• Groups and subgroups goes into more detail on how groups and subgroups work in PGD.

• Creating and joining groups looks at how new PGD groups can be created and how to join PGD nodes to them.

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

• Viewing topology details commands and SQL queries that can show the structure of a PGD cluster's nodes and groups.

• Removing nodes and groups shows the process to follow to safely remove a node from a group or a group from a cluster.

• Heterogeneous clusters looks at how your PGD cluster can interoperate with PGD nodes from earlier editions of PGD.

• Connection DSNs introduces the DSNs or connection strings needed to connect directly to a node in a PGD cluster. It also covers how to use SSL/TLS certificates to provide authentication and encryption between servers and between clients.

• Decoding worker covers a feature of PGD that allows groups of nodes to reduce CPU overhead due to replication.

• Replication slots examines how the Postgres replication slots are consumed when PGD is operating.

• Node recovery details the steps needed to bring a node back into service after a failure or scheduled downtime and the impact it has on the cluster as it returns.

• Maintenance commands through proxies shows how to send maintenance commands to nodes that you can't directly access, such as those behind a proxy.