Remove nodes from a cluster setup for Linux

As an RPA platform administrator, you can remove nodes from a Control Room cluster setup to replace or update them for enhanced performance.

Prerequisites

Ensure the following:

  • Verify that all the primary nodes and databases have backups.
  • Ensure that you have administrator or root privileges on the Control Room servers.
Perform the following steps to remove three nodes (N1, N2, and N3) from a cluster that has six nodes (N1, N2, N3, N4, N5, and N6).

Procedure

  1. Run the following command in the Linux shell to identify the primary node.
    curl -k --user es_client:Automation123 https://172.31.46.2:47599/_cat/nodes
  2. Remove the non-primary nodes N2 and N3 from the cluster.
    1. Log in to the server as an administrator and run the following command to stop all the Control Room services.
      sudo systemctl stop controlroom*
    2. Log in to any of the non-primary nodes.
    3. Edit the cluster.properties file located at /opt/automationanywhere/automation360/config.
    4. Remove the IP addresses for the original three nodes.
      Note: Perform this action for all the nodes in the cluster. When you remove the IP addresses of the original three nodes, do not change their sequence.
    5. Edit the elasticsearch.yml file at /opt/automationanywhere/automation360/elasticsearch/config.
    6. Remove the old IP addresses from the list in the discovery.zen.ping.unicast.hosts attribute.
    7. Restart the non-primary nodes, one at a time.
  3. Remove the primary node N1 from the cluster.
    1. Log in to the server as an administrator and run the following command to stop all the Control Room services.
      sudo systemctl stop controlroom*
    2. Log in to any of the non-primary nodes.
    3. Edit the cluster.properties file and remove the IP address of the old primary node.
    4. Run the following command in any of the other nodes to identify the new primary node.
      curl -k --user es_client:<es password>https://172.31.18.37/_cat/nodes
    5. Edit the elasticsearch.yml file at /opt/automationanywhere/automation360/elasticsearch/config.
    6. Update the IP address of the new primary node in the cluster.initial_master_nodes attribute.
    7. Remove the IP address of the old primary node from the list in the discovery.zen.ping.unicast.hosts attribute.
    8. Run the following command to start the services on each node:
      sudo systemctl start controlroom*
  4. To verify the health of the cluster, run the following command in the command line:
    curl -k --user es_client:<es password>https://172.31.18.37/_cat/nodes
    The replication status turns green when the cluster is fully synchronized. You must wait until the replication status turns green.