The profile files are stored in a special file directory. This directory can be made accessible from all hosts, depending on current requirements, so that they can all access the profile files:
UNIX systems:/usr/sap/<SID>/SYS/profile
Windows systems:\\<SAPGLOBALHOST>\saploc\<SID>\SYS\profile\
Note <SID> is the system ID of the SAP system, and <SAPGLOBALHOST> is the name of the host on which the global profile directory physically exists. saploc is the name of a share; this is the default directory [drive]:\usr\sap.
Note You cannot choose a name for the default profile. It is always called DEFAULT.PFL. You can select any name for an instance profile. The SAP naming convention for instance profiles has the following structure: <SID>_<instance name>_<host name>.