What is a profile and how many types of profiles are avail

A profile in the Sap system is an OS file contains parameters and configuration information of the SAP Instance.

The profiles are located under /usr/sap//SYS/profile

There are three types of profiles available in SAP

1. Start profile: defines the Sap R/3 services to start (different start profiles for different instances).

2. Default profile (system profile): this contains parameter values used by all application servers from the same SAP system.

3. Instance Profile: contains Instance specific parameter values like how many types of work process to be started for an Instance, default logon language, shared memory details etc..  (Different start profiles for different instances).