For z/OS UNIX file access, the user must first have a TSO/E user ID defined to RACF with a z/OS UNIX segment defining the UID and GID. When the PCNFSD authenticate request is received, the Network File System uses the UID and GID associated with the user's RACF profile z/OS UNIX segment, to return in the client's UID and GID credentials. It is recommended that the RACF installation preserve a unique network UID and GID that each user is associated with throughout the network. If there is no z/OS UNIX segment for a user, the client's UID and GID credentials are assigned as presented in the following paragraphs.

If security(saf) or security(safexp) is specified in the site attributes and the client user does not have a valid z/OS UNIX segment, a system assigned UID and GID is returned in the client user credentials.

If security(none) or security(exports) is specified in the site attributes, a system assigned UID and GID is returned in the client user credentials.