Chapter Contents


Using the NFS Client

NFS User Commands

The following commands are used primarily by users who are running NFS client applications:

NFS User Commands
Command Description
NFSLOGIN Authorizes TSO or CMS users to access files via NFS
MOUNT Mounts remote NFS file systems into the NFS client file system structure
UMOUNT Removes a previously established mount

The format that is used to invoke the NFSLOGIN, MOUNT, and UMOUNT commands is generally identical to that shown in the following reference information. Under OS/390, system administration considerations may require use of the TSO CALL command or other techniques. See your system administrator for details. See NFSLOGIN, UMOUNT, and MOUNT for information.


Authorizes TSO or CMS users to access files via NFS

Format 1: NFSLOGIN [ -s server] [ -u username] [ -p password] [ -n ]
Format 2: NFSLOGIN -f

The NFSLOGIN command authorizes TSO or CMS users to access files via NFS. In some cases the NFS client software can determine the correct server and username without your specifying them. If a RACF-compatible security system is installed, the site can define particular mainframe users as having access to specified UNIX userids without requiring a password. If no password is required, and if the other values are correct by default, you do not need to use this command. The login will occur automatically when you access the first NFS file or directory.

The NFSLOGIN command is provided for sites and situations where either a password is needed or the default server or username values must be overridden.

See Logging on to the NFS Network for discussion of NFS login considerations. Also see NFS Security Administration for more information.

The -f option requests a full-screen display. This display has fields for specifying the same information that can be specified on the command line. The full-screen option provides nondisplay password entry.

The server parameter is the host name of the login server that you want to contact. This may differ from the servers on which files are being accessed. The specified host must be running the appropriate login server software. See Installing and Administering the NFS Client for details. You can usually omit this option because the site can set up a default host server at installation time. Note also that, when a security system is installed, the mainframe security administrator controls your access to login servers. Using an unauthorized server causes a RACF violation.

For username, specify your username on the NFS login server. This is often different from your OS/390 or CMS login ID. You do not need to specify a username if the USER environment variable is set to the desired name, or if your login server username is the same as your mainframe userid but converted to lowercase.

If you do not have a RACF-compatible security system, or if you want to login as a username that is not associated with your RACF profile, use the -p option or the password field to specify your password on the login server. The mainframe security system (if present) can also control whether a password will be allowed on your NFS login.

Note that the -p option requires a value. The -n option is required for the special case in which the UNIX (or other login server operating environment) system account has a null password. The -p and -n options are mutually exclusive. Not specifying either -p or -n indicates that the user expects the mainframe security system to authorize access to the login server username. The full-screen display also allows for the special case of a null password.

If the login attempt fails, NFSLOGIN prints a message that describes the reason. Otherwise it prints a message that indicates success. The login fails if the login server is not running on the NFS network.

Note that you need not log out from the login server; your UID and GID permissions expire after you log off TSO or CMS. If you want to access files under a different username, you can issue the NFSLOGIN command again. A login expires after two days. See Diagnosing Problems for more information.

nfslogin -f

Invokes the full-screen login panel.

nfslogin -u bbritten -p ocean

Logs in to the default login server with username bbritten and password ocean .


Mounts remote NFS file systems into the NFS client file system structure.

Format 1: MOUNT server :directory mount-point [options]

The MOUNT command is one method of mounting remote NFS file systems into the NFS client file system structure on the mainframe. This command is useful only when you have configured your session to save file system context. Otherwise, the MOUNT command has no effect when it completes.

The server parameter specifies the name of the NFS server on which the files are physically located. The directory is the name of the directory for the directory tree that you want to mount. It must be a physical filename on that server (it cannot be created by the server's NFS client software).

The mount-point parameter specifies the name of the mainframe NFS client directory on which the remote file system is to be mounted. For the first mount, this must be a slash (/). For subsequent mounts, it must be a valid pathname in the directory structure that was established by existing mounts.

The options string is not required. It specifies mount options for the file system. See Mount Options. The string of options must be separated by commas, with no intervening spaces.

You cannot mount a file system on a directory that is already being used as a mount point. You must first unmount the existing file system with the UMOUNT command.

Be aware that mounts made by this command are preceded by mounts from any fstab file.

These examples assume that there is no fstab file and that file system context is being saved.
mount byrd.unx:/local/u/bill /

Mounts bill's home directory on byrd.unx as the root directory on the mainframe.

mount server.unx:/tools /tools ro

Adds the /tools directory from server.unx as a subdirectory and treats it as read-only.


Removes a previously established mount

Format 1: UMOUNT mount-point

The UMOUNT command removes a previously established mount. This command is useful only when you have configured your session to save file system context. Otherwise, the MOUNT command has no effect when it completes.

The mount-point parameter specifies a mainframe pathname to a directory from which a remote file system will be unmounted. The directory must have been used in a previous mount operation.

You cannot unmount the root directory. If you want to mount a different root directory, delete the mnttab file and then mount the new root directory. The NFSLOGIN command also deletes the mnttab file.

You cannot unmount a file system that has other directories mounted over it, or a file system that contains your current directory. Attempting to do so results in the following message:

UMOUNT failed: file or record in use.

This example assumes that file system context is being saved.
umount /tools

Removes the file system that was previously mounted at /tools . If the file system mounted at / had any files in its tools subdirectory, these now become visible.

Chapter Contents



Top of Page

Copyright © 2001 by SAS Institute Inc., Cary, NC, USA. All rights reserved.