The remote file system can be mounted only after the z/OS UNIX file system, z/OS NFS client, and TCP/IP initializations are complete. The mount can only be performed by a z/OS UNIX superuser (uid=0 ). For more information about the TSO MOUNT command, when used with the z/OS NFS client, see Mount command syntax and examples.

When using the automount facility of z/OS UNIX System Services, the remote file system is mounted on its first data access attempt if it is not already mounted.

When the automount facility is used to manage remote NFS mount points, the z/OS NFS user could experience ESTALE/EIO errors if the automounter unmounts the accessed mount point when the time limits specified by the automount duration and delay parameters have been exceeded. The automount default, DURATION=NOLIMIT, disables the DURATION timeout period. The DELAY for unmounting file systems should be longer than the time z/OS NFS clients are likely to keep z/OS NFS mounts to the files and directories active. For more information about the z/OS UNIX automount facility, see z/OS UNIX System Services Planning and z/OS UNIX System Services Command Reference.

The remote file system must be mounted on the z/OS UNIX file system prior to any reference being made to the remote data. Once mounted, the remote file system can be treated as an extension of the local z/OS UNIX file system.