Adding a Node to an Existing Cluster

You can add an additional node to an existing cluster at any time without causing the active server to fail over. Vocera supports up to four servers in a cluster.

To add a new server to an existing cluster:

  1. On the new server that you want to add to the cluster, use the Vocera Control Panel to stop the Vocera Voice Server.
    Important: Keep the Vocera Voice Server on the new standby node stopped while you configure the active node. This ensures that when you start the standby node it will perform a remote restore from the active node because it has been running longer. Otherwise, you may unintentionally cause the active node to perform a remote restore from the new standby node.
  2. Configure the active node to recognize the new server.
    1. Log in to the Administration Console of the active node.
    2. Click System in the navigation bar.
    3. Click the Cluster tab to display the Cluster Setup page.
    4. Click Add Server.
      The Add/Edit Cluster Server dialog box appears. Use this dialog box to add servers to a cluster.
    5. Enter the IP address of a standby server and a brief description.
    6. Click Add to save changes, close the Add/Edit Cluster Server dialog box, and display the Cluster Setup page.
      When you are finished, the Status column for the new server displays “Unsaved”.
    7. Click Save Changes.
      Vocera saves the information and displays the first tab of the System screen, License Info.
    8. Click the Log Out button at the top of the page.
      The system logs you out and displays the Log In page of the Administration Console.
  3. On the new server that you want to add to the cluster, use the Vocera Control Panel to start the Vocera Voice Server.
  4. Configure the new server to recognize the active node.
    1. Log in to the Administration Console of a server you want to use as a standby node.
    2. Click System in the navigation bar.
    3. Click the Cluster tab to display the Cluster Setup page.
      The IP address of the current server appears in the server list. The Status column displays “Unsaved”.
    4. Check Enable Cluster.
      The buttons for setting up and maintaining the cluster appear to the right of the server list.
    5. Click Add Server.
      The Add/Edit Cluster Server dialog box appears. Use this dialog box to identify the server you are using as the active server.
    6. Enter the IP address of the active server and a brief description, and then click the Add button to save changes, close the Add/Edit Cluster Server dialog box, and display the Cluster Setup page.
      Note: You do not have to add the IP address of any other cluster servers to the list. When you restart the server you are configuring, it will download this information from the active server.
    7. Click Save Changes.
      Vocera saves the information and displays the first tab of the System screen, License Info.
    8. Click the Cluster tab to display the Cluster Setup page.
    9. Click Force Restart.
      A dialog box asks you to confirm restarting the server.
      Note: If you do not click Force Restart, within a minute the cluster's self-healing mechanism will cause the server to automatically enter discovery mode, perform a remote restore from the active server, and then come online as a standby node.
    10. Click OK.
      Vocera logs you out of current server’s Administration Console, and the current server restarts as a standby node in the cluster.
  5. If your organization uses Staff Assignment, update the cluster list in the Staff Assignment configuration file (app.config) on each standby node:
    1. On each standby node, open the following file in a text editor:
      \vocera\data\applications\staffassignment\app.config
    2. Edit the serverIP property to include the comma-separated list of IP addresses for the Vocera Voice Server cluster. Enter numeric IP addresses using dotted-decimal notation. Do not enter domain names.
    3. Save your changes.
    Note: You do not need to update the cluster list in the Staff Assignment configuration file on the active node. The serverIP property is updated automatically on the active node when someone logs into Staff Assignment.
  6. Check your work.
    1. Log in to the Administration Console of the active Vocera Voice Server. Make sure each server shows up in the list on the Cluster Setup page with the proper status of “active” or “standby”.
    2. Fail over cluster control several times, until you confirm that the cluster behaves as you expect. See the Vocera Voice Server Installation Guide.