What this module does

Cluster nodes manage database and application membership. They do not promise automatic workload scheduling, geographic routing or seamless autoscaling.

Before you start

Private network reachability between nodes.
Administrator API token for the node being attached.
Compatible Callaba versions and a current configuration backup.

Settings explained

These are the controls an operator needs to understand. Internal field names and implementation events are intentionally omitted.

Node identity

Describe the trusted member.

Name: Operator-facing node name.
Node type: Master, Slave or Test role supported by the UI.
Private host: Reachable private address used between nodes.
Avoid a public address when a private path is available.
API token: Administrator token used to establish trusted management.
Treat it as a secret.
Active: Lifecycle state of the registered node.

Safe first workflow

01
Back up the current configuration and verify private network connectivity.
02
Create the node with its intended role, private host and administrator token.
03
Attach the node and wait for membership to settle.
04
Start it and verify reachability plus the expected database membership.
05
Test detach and recovery procedure outside a production incident.

Workflow examples

Use this when

Add a trusted slave node

A self-hosted deployment needs a supported additional cluster member.

Primary nodeCurrent cluster

Private networkReachability

Slave nodeAttach + start

MembershipVerified state

Animated workflow diagram: Add a trusted slave node

How to build it

1
Confirm compatible versions, backup and private connectivity.
2
Register the Slave with its private host and token.
3
Attach and start the node in a controlled window.
4
Verify node state and database membership before using it operationally.

Verify the result

The node is reachable over the intended private path.
Role and lifecycle state match the planned topology.
Attach/detach operations produce the expected membership state.

Troubleshooting

Attach fails

Check

Check private reachability.
Verify the node token and version.
Confirm the role and current membership.

Then do this

Correct trust or network prerequisites before repeating the attach action.

Cluster nodes