When you want to add an additional host (node) for an already Connections Installation, you have to add additional Application Servers in your Clusters.
So you install WebSphere Application Server on the new host, create a new node and federate it into your deployment manager. Do not forget to create a service, that the new nodeagent is started on server start and change the monitoring policy state.
You can add these through ISC, but when you have a midsize or large deployment, this is a boring task.
We provide a script, which asks you for the node where the servers should be created and the number they should have. After this you will be asked to select the Clusters:
After this the nodeagent syncs the application and the new node can work. You should recreate the WebSphere Plugin and restart IHS!
In the IBM Connections Documentation there are additional tasks to do, like configuring the search index for working with multiple nodes!