i used Elmah in mvc and i force Elmah to log the error from try catch  in action. suppose i have layer application where i have UI, DAL and  BAL. now tell me when error occur in BAL or DAL then how can i instruct  elmah to log that?
 i add elmah in UI layer. do i need to create a separate project in  same solution for elmah and expose some class function which will be  called from UI, DAL and BAL?
 please guide me how project structure should look like as a result i can log error by elmah from any layer.
 discuss with little sample code and example.