No. The underlying communication mechanism (e.g. PI SDK, AF SDK) know about the IP addresses/hostnames of ALL the members of the collective, and will automatically switch over for the benefit of the client application.
Since this is not a programming or systems integration question, I would kindly recommend you contact our regular technical support for follow-up questions on this topic - they are better equipped and staffed to answer system administration/configuration and end-user questions. Also, you can read the High Availability guides available on the vCampus Library or the Technical Support website.