BODS v 4.0.2 DR Design

Hi Experts,

Hoping to get help in understanding how to design DR for BODS 4.0.2.

We already have BODS 4.0.2 (web and app tier on separate windows servers) and database is SQL Server 2008. I was never involved in BODS installation and have no experience prior to this. So appreciate if you can share documents on

Step by step documents to do BODS install.

How BODS DR should be designed and implemented - replication of SQL database is enough or we need to enable sync/replication of Web/App Tier also.

Thanks

Davinder