Configuring redundancy

Glossary:

• Redundancy pool: 

  Set of servers including a Master Manager, a Backup Manager and a Redundancy Arbiter, all using a static IP address within the same LAN.

• Master Manager:  

  The Master Manager is the Manager server that is used for all operations when the system is fully operational (nominal use).  
  In nominal use, Master Manager has Primary status.

• Backup Manager:  

  The Backup Manager is the server ready to take over operations in case of Master Manager failure within a Manager redundancy pool.

• Redundancy Arbiter:  

  Service running on a third server (could be a virtual host). It participates to the election of the Manager taking Primary status, within the database replica set. It does not host replicated data.

• Virtual IP address:  

  Address managed by Master Manager and Backup Manager and hosted by either Master Manager or Backup Manager, according to the operating state of the redundancy pool.  
  Please note that this static address must not be included in the dynamic range of the DHCP server. Furthermore, it should not be associated to a MAC address.

• Primary status:  

  Status that gives read-write access to database, authorizes the connection of field units.  A Manager with this status hosts the virtual IP address.

• Online status:  

  Status that gives a read-only access to database and that does not allow the connection of field units. With this status, the Manager web user interface is limited to configuration items.

To configure a redundancy, you need to configure IP settings that ensure connection between all servers within the redundancy pool (Master, Backup, and Arbiter).

Before starting configuration, make sure that:

• you saved the database of the Master server.
• the arbiter service is newly installed.

To configure a redundancy:

1. Configure IP settings for the Backup Manager:
   1. Connect to the Web interface of the Manager used as a Backup Manager.
   2. In the menu bar, click on Settings.
   3. Click on General.
   4. Under the Server Redundancy section, select Backup running mode.
   5. Enter the IP address of the Master Manager.
   6. Verify the Backup Manager local IP address.
   7. Enter the virtual IP address dedicated to the redundancy pool.

   8. Click on Save. The Backup Manager reboots and is put on hold while the Master Manager is being configured.
      

      

      

      Note

      Should the Master Manager be not configured within 10 minutes, the Backup Manager restarts as a standalone Manager.

2. Configure IP settings for the Master Manager:
   1. Connect to the Web interface of the Manager used as the Master server.
   2. In the menu bar, click on Settings.
   3. Click on General.
   4. Under the Server Redundancy section, select Master running mode.
   5. Verify the Master Manager local IP address.
   6. Enter the IP address of the Backup Manager.
   7. Enter the virtual IP address dedicated to redundancy.
   8. Enter the IP address of the Redundancy Arbiter.
   9. (Optional) Enable the Active checkbox to act as primary when up.

   10. Click on Save.
       

       

       
       
       The Master Manager reboots.  
       Once all servers are configured the user interface is modified:
       A - The About Section indicates the server running mode (Backup or Master). 
       B - Note that the Backup Manager user interface is lightened. Only Logs page, General settings, and a light admin menu are accessible.  
       C - Moving the mouse over the icon displays the status of servers.  
       

       

       

       Note

       • The initial IP settings of various Manager servers are explained in the Installation Guide.
       • The Backup Manager and the Redundancy arbiter are being configured. Please note that during configuration, servers' web interfaces cannot be accessed.  Should the configuration be not effective within 10 minutes, the Master Manager restarts as a standalone Manager.
3. From Field Unit interfaces, you need to set destination profiles for a connection to the virtual IP address that you dedicated to redundancy:
   1. Make sure that you selected "Manager" as destination profiles types.
   2. As the Host IP address, enter the virtual IP address dedicated to redundancy.
   3. It is advised to enable the autoconnection option to ensure that field units reconnect automatically in case of Master Manager or Backup Manager failover.