Setting up of A-A cluster is very easy. Make sure you have at least 3 UM nodes running on the different host machine and you can create the cluster via UM EM.
Also, make sure that your license keys supports clustering and have the latest UM Server and Client level fixes installed as you may face some issues while you are performing some load test by bringing down the master node down so that one of the other two nodes will be master and processing continues (Quorum)
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