I have already installed SQL Server in failover cluster. Which consists of two nodes.
I have requirements which need SSAS (SQL Server Analysis Service) and SSRS (SQL Server Reporting Service)
After many tries, I failed!!!
After some search… I found the following line in SQL Server 2008 R2 White Paper
Note: SQL Server 2008 does not support adding features to an existing failover cluster instance, so Analysis Services cannot be added to an existing instance of SQL Server. To share a resource group with an instance of SQL Server, you must choose to install Analysis Services during the initial installation of SQL Server.
In shourcut: you can’t install SSAS or SSRS on an existing cluster.
Adding third or new node (server) to the cluster and install on this node the SSAS and SSRS. (this solution is my suggestion)