ROOTPATH specifies the full pathname, including the device or filename, of the initial chunk of the root dbspace. ROOTPATH is stored in the reserved pages as a chunk name.
On UNIX, you must set the permissions of the file that ROOTPATH specifies to 660, and the owner and group must both be informix. On Windows, a member of the Informix-Admin group must own the file that ROOTPATH specifies.
If you use unbuffered disk space for your initial chunk on UNIX, it is recommended that you define ROOTPATH as a pathname that is a link to the initial chunk of the root dbspace instead of entering the actual device name for the initial chunk.