Adding Nodes to the Historical Database Cluster

The first time you set up a Historical database server in your Oracle Communications Unified Assurance environment, after installing Unified Assurance on the server, you create a database cluster when you run AnalyticsWizard. Initially, this is a standalone cluster with a single node.

You can add new nodes and set up a redundant cluster right away or later, by installing Unified Assurance on additional servers and running AnalyticsWizard on them.

Before running AnalyticsWizard, confirm that the Historical database cluster is in green or yellow status. See Checking Cluster Status.

AnalyticsWizard automatically detects if a server is primary or redundant and if a Historical database cluster already exists in the environment. If the database exists, AnalyticsWizard prompts you to add the server to the cluster.

After running AnalyticsWizard:

  1. Update the number of replicas for event, flow, journal, and log indexes. See Increasing Replicas for Indexes.

  2. If you also have a microservice cluster, update the microservice cluster configuration. See Updating Microservice Cluster Configurations.

For information about installing Unified Assurance on a new server and running AnalyticsWizard, see the following in Unified Assurance Installation Guide:

For AnalyticsWizard usage details, see AnalyticsWizard.

Checking Cluster Status

You can use the OpenSearch administration console to query the Historical database for the cluster status.

  1. From the main navigation menu, select Analytics, then Events, then Administration, and then Console.

  2. Enter the following request in the console and click the arrow to run the request:

    GET _cluster/health

    The response should contain "status": "green" or "status": "yellow". Either status means all primary shards are allocated to nodes.

In the OpenSearch documentation, see Cluster health for information about the fields returned in the response and Cluster APIs for general information about the OpenSearch cluster APIs.

Increasing Replicas for Indexes

When you add a new node to the cluster, the default number of replicas for indexes is 0. To support high availability, you must update the number of replicas for each index in the index templates.

  1. From the main Unified Assurance navigation menu, select Analytics, then Events, then Administration, and then Management.

  2. Click Index Management.

  3. From the list on the left, under Index Management, click Templates.

  4. For each of the default templates, repeat the following:

    1. Click the template name. For example, template-eventanalytics.

    2. Click the Configuration tab.

    3. Under Template Definition, set Number of replicas to a number greater than 0, but no more than the number of nodes in the cluster.

      Note:

      By default, Number of primary shards is set to 1. The number of replicas applies to each shard, so if you are using more shards, you will need more nodes in the cluster. For example, if you set shards to 2 and replicas to 2, there will be two replicas for each shard, and you must have at least three nodes in the cluster.

    4. Click Save.

Updating Microservice Cluster Configurations

During an initial installation, you typically run AnalyticsWizard on all servers in the Historical database cluster before setting up a microservice cluster. In this situation, the microservice cluster is created with the correct information about the Historical database nodes.

However, in some situations, such as during database migration or when adding new nodes to an existing Historical database cluster later, you run AnalyticsWizard after the microservice cluster is already set up. In these situations, you must update the microservice cluster configuration with the new Historical database information.

To do this, run the following command as the root user on one of the servers where the Cluster.Master role is installed:

$A1BASEDIR/bin/cluster/clusterctl update-config