1.1 What Is Samba?

Samba is a suite of Unix applications that speak the Server Message Block (SMB) protocol. Microsoft Windows operating systems and the OS/2 operating system use SMB to perform client-server networking for file and printer sharing and associated operations. By supporting this protocol, Samba enables computers running Unix to get in on the action, communicating with the same networking protocol as Microsoft Windows and appearing as another Windows system on the network from the perspective of a Windows client. A Samba server offers the following services:

• Share one or more directory trees

• Share one or more Distributed filesystem (Dfs) trees

• Share printers installed on the server among Windows clients on the network

• Assist clients with network browsing

• Authenticate clients logging onto a Windows domain

• Provide or assist with Windows Internet Name Service (WINS) name -server resolution

The Samba suite also includes client tools that allow users on a Unix system to access folders and printers that Windows systems and Samba servers offer on the network.

Samba is the brainchild of Andrew Tridgell, who currently heads the Samba development team. Andrew started the project in 1991, while working with a Digital Equipment Corporation (DEC) software suite called Pathworks, created for connecting DEC VAX computers to computers made by other companies. Without knowing the significance of what he was doing, Andrew created a file-server program for an odd protocol that was part of Pathworks. That protocol later turned out to be SMB. A few years later, he expanded upon his custom-made SMB server and began distributing it as a product on the Internet under the name "SMB Server." However, Andrew couldn't keep that name ”it already belonged to another company's product ”so he tried the following Unix renaming approach:

 $  grep -i '^s.*m.*b' /usr/dict/words  

And the response was:

 salmonberry samba sawtimber scramble 

Thus, the name "Samba" was born.

Today, the Samba suite revolves around a pair of Unix daemons that provide shared resources ”called shares or s ervices ”to SMB clients on the network. These are:

smbd

A daemon that handles file and printer sharing and provides authentication and authorization for SMB clients.

nmbd

A daemon that supports NetBIOS Name Service and WINS, which is Microsoft's implementation of a NetBIOS Name Server (NBNS). It also assists with network browsing.

Samba is currently maintained and extended by a group of volunteers under the active supervision of Andrew Tridgell. Like the Linux operating system, Samba is distributed as open source software (http://opensource.org) by its authors and is distributed under the GNU General Public License (GPL). Since its inception, development of Samba has been sponsored in part by the Australian National University, where Andrew Tridgell earned his Ph.D. Since then, many other organizations have sponsored Samba developers, including LinuxCare, VA Linux Systems, Hewlett-Packard, and IBM. It is a true testament to Samba that both commercial and noncommercial entities are prepared to spend money to support an open source effort.

Microsoft has also contributed by offering its definition of the SMB protocol to the Internet Engineering Task Force (IETF) in 1996 as the Common Internet File System (CIFS). Although we prefer to use the term "SMB" in this book, you will also often find the protocol being referred to as "CIFS." This is especially true on Microsoft's web site.