N-to-N Configuration

An N-to-N configuration refers to multiple service groups running on multiple servers, with each service group capable of being failed over to different servers in the cluster. For example, consider a four-node cluster with each node supporting three critical database instances.

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N-to-N Configuration

If any node fails, each instance is started on a different node, ensuring no single node becomes overloaded. This configuration is a logical evolution of N + 1: it provides cluster standby capacity instead of a standby server.

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N-to-N Failover

N-to-N configurations require careful testing to ensure all applications are compatible. Applications must also have complete control of where service groups fail when an event occurs.