Enabling high availability on cluster members by using the Amlen WebUI

You can add high availability (HA) to members of your cluster by using the Amlen WebUI.

System administrators can add HA to members of a cluster by using the Amlen WebUI, or by using REST Administration APIs. For more information about using REST Administration APIs to add HA to cluster members, see Enabling high availability on a member of a cluster by using REST Administration APIs.

In this scenario, an Eclipse Amlen server that is a member of a cluster but has HA disabled is paired with another Eclipse Amlen server to act as its backup. System administrators can configure a pair of servers for high availability by using the Amlen WebUI. In this scenario, Server A is already member of a cluster, and becomes the primary node. Server B becomes the standby node in the HA pair. Server A can be a server that has data on it. Server B must be a newly installed Eclipse Amlen server or you must complete Step 1 to remove any pre-existing data.

  1. Optional: If Server B is a newly installed server, you do not need to perform this step. If Server B is not a newly installed server and has been used for messaging services, you must delete any JMS queues that exist on the server and then clean the store.

    For more information about deleting message queues, see Configuring queues by using the Amlen WebUI.

    For more information about cleaning the store, see Restarting, stopping, and viewing the status of the Eclipse Amlen server by using the Amlen WebUI.

  2. Optional: Eclipse Amlen supports user provided TLS credentials for High Availability Pairing. Providing the credentials prior to creating the HA pair is recommended to avoid migrating the cluster. See High Availability Pairing: User Provided TLS Credentials.
  3. Configure HA on Server A.
    1. Ensure that you are managing Server A. In the Server menu, select High Availability
    2. Click Edit in the Configuration panel.
    3. Select High Availability Enabled
    4. Complete the High Availability Group field.
      The value must be the same on Server A and Server B.
    5. Under Replication and Discovery Addresses:
      1. Type the IP address of the replication interface of the local node in Local Replication Address. For example, 192.0.2.0
      2. Type the IP address of the discovery interface of the local node in Local Discovery Address. For example, 192.0.3.0
      3. Type the IP address of the discovery interface on the other node (Server B) in the HA pair in Remote Discovery Address. For example, 192.0.2.2
    6. Expand the Advanced Settings section by clicking the twistie.
      1. Ensure that Auto-detect is selected as the Startup Mode.
      2. Select the When both nodes start in auto-detect mode, this node is the preferred primary node check box.
      3. In the Discovery Timeout field, type the amount of time in seconds that within which an server that is started in auto-detect mode has to connect to the other server in the HA pair.
      4. In the Heartbeat Timeout field, type the amount of time within which an server has to determine if the other server in the HA pair has failed.
    7. Click Save.
    8. Click Restart Later.
  4. Configure high availability on Server B.
    It is best practice to use a newly installed Eclipse Amlen server to act as the standby server in the HA pair.
    1. Ensure that you are managing Server B. In the Server menu, select High Availability
    2. Click Edit in the Configuration panel.
    3. Select High Availability Enabled
    4. Complete the High Availability Group field.
      This value must match the value on Server A.
    5. Under Replication and Discovery Addresses:
      1. Type the IP address of the replication interface of the local node in Local Replication Address. For example, 192.0.2.2
      2. Type the IP address of the discovery interface of the local node in Local Discovery Address. For example, 192.0.3.2
      3. Type the IP address of the discovery interface on the other node (Server A) in the high availability pair in Remote Discovery Address. For example, 192.0.2.0
    6. Expand the Advanced Settings section by clicking the twistie.
      1. Ensure that Auto-detect is selected as the Startup Mode.
      2. Ensure that the When both nodes start in auto-detect mode, this node is the preferred primary node check box is not selected.
      3. In the Discovery Timeout field, type the amount of time in seconds that within which an server that is started in auto-detect mode has to connect to the other server in the HA pair.
      4. In the Heartbeat Timeout field, type the amount of time within which an server has to determine if the other server in the HA pair has failed.
    7. Click Save
    8. Click Restart Later
  5. Configure and enable cluster membership on Server B.
    1. Ensure that you are managing Server B. In the Cluster menu, select Join/Leave
    2. Click Edit in the Configuration panel.
      1. Type the cluster name in the Cluster Name field. This value must match the name of the cluster of which Server A is a member.
    3. Click Save.
    4. Ensure that the Address and Port in the Control Interface and Messaging Interface sections are correct. If they are not correct, click Edit and specify correct values.
    5. Ensure that you also include any other cluster membership configuration parameters that you need so that Server B and Server A can identify and connect to the other members of the cluster, for example, if Server A is using external addresses or ports.
      For more information about configuring cluster membership on a server, see Configuring cluster membership by using the Amlen WebUI.
    6. Click Restart server and join cluster in the Status pane.
  6. Restart Server A.
    1. Ensure that you are managing Server A. In the Server menu, select Server Control
    2. Click Restart the server, then click Restart
  7. After your servers have restarted, verify the status of your servers.
    1. On Server A, check the Status drop-down list and verify that the status displays the values High Availability: Primary node and Cluster: Active
    2. In the Cluster menu, click Status
    3. In the Cluster Status Data pane, ensure that the other members of the cluster are visible in the table.
    4. On Server B, check the Status drop-down list and verify that the status displays the values High Availability: Standby node and Cluster: Standby
  8. Force a failover operation in order to verify that Server B is correctly configured to work with the cluster.
    You can force a failover operation by restarting Server A.
    1. On Server A, click Server Control in the Server menu.
    2. Click Restart the server, then click Restart
  9. Verify the status of your servers after the failover.
    Verify that Server B is now the primary node and Server A is now the standby node.
    1. On Server B, check the Status drop-down list and verify that the status displays the values High Availability: Primary node and Cluster: Active
    2. In the Cluster menu, click Status
    3. In the Cluster Status Data pane, ensure that the other members of the cluster are visible in the table.
    4. On Server A, check the Status drop-down list and verify that the status displays the values High Availability: Standby node and Cluster: Standby