Clearwater Automatic Clustering and Configuration Sharing

Clearwater has a feature that allows nodes in a deployment to automatically form the correct clusters and share configuration with each other. This makes deployments much easier to manage. For example:

  • It is easy to add new nodes to an existing deployment. The new nodes will automatically join the correct clusters according to their node type, without any loss of service. The nodes will also learn the majority of their config from the nodes already in the deployment.
  • Similarly, removing nodes from a deployment is straightforward. The leaving nodes will leave their clusters without impacting service.
  • It makes it much easier to modify configuration that is shared across all nodes in the deployment.

This features uses etcd as a decentralized data store, a clearwater-cluster-manager service to handle automatic clustering, and a clearwater-config-manager to handle configuration sharing.

Is my Deployment Using Automatic Clustering and Configuration Sharing?

To tell if your deployment is using this feature, log onto one of the nodes in your deployment and run dpkg --list | grep clearwater-etcd. If this does not give any output the feature is not in use.

Migrating to Automatic Clustering and Configuration Sharing

Deployments that are not using the feature may be migrated so they start using it. To perform this migration, follow these instructions.