How to setup RFC Connection for SAPOSS?

Dear Experts,

I tried to setup the RFC connection for SAPOSS based on the following settings, but when I test connection, it failed.

Target system : OSS

Msg. Server : ... ( this where I stuck which I'm not sure what to fill in)

Group : EWA

Client : 001

User : OSS_RFC

Password : CPIC

Does anyone know the right settings?

Regards,

Abraham