@Anshu: Check on these lines
1- What is the data source?(For eg: Oracle, SQL server........)
2- Did you configure and check the data source connectivity on all nodes on the BusinessObjects server(linux)?
3- If you have set up the data source then is it 32-bit data connection or 64-bit?
4- Assumption: If you are using Oracle as data source for CMS and same for reporting then you need to configure both (32-bit and 64-bit data connection)connections on the server.