High availability of cluster services

When we plan the architecture of your cluster, consider the services that we use in the environment along with your failover requirements for high availability. Include an External Reference Entity (ERE) for the primary and secondary masters in the architecture to assist in the failover process.

• Cluster service considerations
  A cluster requires at least one master, called the primary master, which provides the cluster services. For failover purposes in a cluster with multiple nodes, we can configure up to three more masters in the environment. The required number of masters depends on which services we use and your failover requirements.
• Failover in a cluster
  The distributed session cache, internal runtime database, geolocation database, and configuration database have varying failover capabilities in a clustered environment.
• External Reference Entity
  To prepare for failover situations, configure an External Reference Entity (ERE) for the primary and secondary master nodes.

Parent topic: Cluster support