According to my experience you can only configure one IS in MWS and need a common database if you want to monitor several Process Engines. The fact that you can configure several servers in Server Settings does not help for independent Process engines with different databases, but in fact I did 't try this setup as I didn’t expected it to work.
Task Engine is running on MWS but needs one IS (configured in “Task Engine Settings”) to talk to the Process Engines database and receive events.
MWS Monitor needs one IS configured in “Integration Server (Process Engine Host)” to connect to the process audit database and send events for process control.
However several IS can host the process engine as monitoring and controlling the processes by MWS is done via database and broker.
As MWS needs to send and receive events for activating and deactivating processes I would expect your environment to work with a single MWs instance. I think you need one broker and a common database for the affected pools. But again I didn’t try to setup an environment like this.
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