Configuring for High Availability

Standalone controller operation provides management for the OpenFlow switches in a network. However, it does not provide high availability (HA), with the result that a controller failure leaves the network in an unmanaged state. Configuring a team of controllers and one or more corresponding controller regions creates a high availability network with failover capability, resulting in a continuously managed network in the event that a controller in the team goes down. Controller teaming also provides centralized controller configuration and monitoring.

You can also view your team configuration using the UI, see Viewing your team configuration using the UI.

High Availability best practices

  • Ensure the team and region configuration meets all of the requirements for teaming. For details, see Requirements for teaming

  • Ensure that IP routing configuration in the controller domain enables the controller team IP address to be reached from all areas of the domain.

  • If any application installed on the controller uses the Cassandra database, run the Cassandra nodetool repair command every 10 days. For details, see Manually synchronizing Cassandra database nodes using nodetool repair utility.

  • Before you create the team, configure NTP such that all the controllers that will be in the team use the same local NTP server. Using the same NTP server for all controllers helps to ensure that the controller clocks remain synchronized. Keeping the system clocks synchronized is especially important for applications that use the Cassandra database. For details, see Configuring the controllers to use the same local NTP server.

  • Either use the same Keystone server for authentication for all three controllers in the team , or use a local Keystone server for each controller in the team. For details on security, see Security.

  • To use TLS connections for communications between the switch and the built-in OpenFlow controller module of the HPE VAN SDN Controller, Hewlett Packard Enterprise recommends that all controller and device certificates be signed by the same CA. For information about configuring TLS on a switch, see the documentation for the switch.

  • If you are configuring web proxy servers, ensure that you include the team IP address and the IP addresses for all three controllers in the team in the /etc/init/sdnc.conf file. After editing the sdnc.conf file all three controllers will need to be restarted. For details, see Obtaining applications from the Hewlett Packard Enterprise SDN App Store