Networking overview

Distributed filesystems

Files can be shared across a network when a server exports directories to be shared and clients mount the directories to access the files in them. Filesharing under the SCO OpenServer Desktop and Enterprise systems is provided by:


The SCO Network File System (NFS) is a product that enables you to export and mount filesystems across a network. This allows users on a local machine, or client, to access specified files and directories from a remote machine, or server, without the time-consuming process of remote logins or machine-to-machine file copying.

In addition to exporting native UNIX filesystems, SCO NFS can export DOS, LAN Manager, and SCO Gateway for NetWare filesystems.


automount allows remote NFS filesystems to be mounted automatically and transparently. Whenever a user on a client machine running automount invokes a command that accesses a remote file or directory (such as when opening a file with an editor), the hierarchy to which that file or directory belongs is mounted and remains mounted for as long as it is needed. No mounting is done at boot time, reducing significantly the time needed to boot up.


The Network Lock Manager (NLM) network service consists of a loadable device driver and a set of daemons that permit both advisory and mandatory file and record locking on local files. Only advisory file and record locking are supported on remote SCO NFS files. The NLM package includes the SCO NFS Status Monitor, which works in conjunction with the NLM to determine when a remote host has recovered after a crash.


The Remote Execution (REX) service is a remote command service. It allows users to export their user environments to remote servers. These servers execute commands that can access files in the user's current directory and allow the execution of interactive processes such as full-screen editors. REX consists of a set of utilities, commands, and library functions.

NOTE: SCO OpenServer offers two additional products that provide distributed filesystem and printing services: SCO Advanced File and Print Server and Samba File and Print Server for SCO OpenServer. These products are included on the Optional Services CD-ROM. See the Optional Services README files for more information.

Configuring NFS

To configure file sharing using NFS, you must:

Once the daemons are running and the filesystems exported, remote filesystems can be mounted by any client with NFS daemons running.

Administering NFS

There are five ways to remote mount exported filesystems:

NOTE: Entries in /etc/default/filesys and automount are mutually exclusive methods of remote mounting. If both are configured, automatic mounting is thwarted.

NIS can be used in conjunction with automount to ensure that each NIS system can automatically mount filesystems from the same set of NFS servers. In this case, automount maps are maintained on the NIS master server and distributed as NIS maps to other NIS systems. Local variations can be made to NIS-distributed automount maps. See ``Managing automount with NIS''.

Administering NFS entails the regular execution of common tasks, including:

See also:

Next topic: Remote installation and software administration
Previous topic: Distributed user applications

© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003