In this blog post, we demonstrate how to convert a single standalone cluster into a Composite Primary/DR topology running in two data centers.

Our example starting cluster has 5 nodes (1 master and 4 slaves) and uses service name alpha. Our target cluster will have 6 nodes (3 per cluster) in 2 member clusters alpha_east and alpha_west in composite service alpha.

This means that we will reuse the existing service name alpha as the name of the new composite service, and create two new service names, one for each cluster (alpha_east and alpha_west).

Below is an INI file extract example for our starting standalone cluster with 5 nodes:

[defaults]
...

[alpha]
connectors=db1,db2,db3,db4,db5
master=db1
members=db1,db2,db3,db4,db5
topology=clustered

To convert the above configuration to a Composite Primary/DR:

1. First you must stop all services on all existing nodes:

   shell> stopall
   

   …

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