cleanup typos in the %a description (mentioned by <HotaruT> on IRC)

[tprouty/samba.git] / docs / manpages / smb.conf.5.xml

<refentry id="smb.conf.5" xmlns:xi="http://www.w3.org/2003/XInclude">
        
<refmeta>
        <refentrytitle>smb.conf</refentrytitle>
        <manvolnum>5</manvolnum>
</refmeta>


<refnamediv>
        <refname>smb.conf</refname>
        <refpurpose>The configuration file for the Samba suite</refpurpose>
</refnamediv>

<refsect1>
        <title>SYNOPSIS</title>

        <para>The <filename moreinfo="none">smb.conf</filename> file is a configuration  
        file for the Samba suite. <filename moreinfo="none">smb.conf</filename> contains  
        runtime configuration information for the Samba programs. The <filename moreinfo="none">smb.conf</filename> file 
        is designed to be configured and  administered by the <citerefentry><refentrytitle>swat</refentrytitle> 
        <manvolnum>8</manvolnum></citerefentry> program. The complete
        description of the file format and possible parameters held within
        are here for reference purposes.</para> </refsect1>

<refsect1 id="FILEFORMATSECT">
        <title>FILE FORMAT</title>

        <para>The file consists of sections and parameters. A section 
        begins with the name of the section in square brackets and continues 
        until the next section begins. Sections contain parameters of the 
        form</para>

        <para><replaceable>name</replaceable> = <replaceable>value
        </replaceable></para>

        <para>The file is line-based - that is, each newline-terminated 
        line represents either a comment, a section name or a parameter.</para>

        <para>Section and parameter names are not case sensitive.</para>

        <para>Only the first equals sign in a parameter is significant. 
        Whitespace before or after the first equals sign is discarded.
        Leading, trailing and internal whitespace in section and parameter 
        names is irrelevant. Leading and trailing whitespace in a parameter 
        value is discarded. Internal whitespace within a parameter value 
        is retained verbatim.</para>

        <para>Any line beginning with a semicolon (<quote>;</quote>) or a hash (<quote>#</quote>) 
        character is ignored, as are lines containing only whitespace.</para>

        <para>Any line ending in a <quote>\</quote> is continued
        on the next line in the customary UNIX fashion.</para>

        <para>The values following the equals sign in parameters are all 
        either a string (no quotes needed) or a boolean, which may be given 
        as yes/no, 0/1 or true/false. Case is not significant in boolean 
        values, but is preserved in string values. Some items such as 
        create modes are numeric.</para>
</refsect1>

<refsect1>
        <title>SECTION DESCRIPTIONS</title>

        <para>Each section in the configuration file (except for the
        [global] section) describes a shared resource (known
        as a <quote>share</quote>). The section name is the name of the 
        shared resource and the parameters within the section define 
        the shares attributes.</para>

        <para>There are three special sections, [global],
        [homes] and [printers], which are
        described under <emphasis>special sections</emphasis>. The
        following notes apply to ordinary section descriptions.</para>

        <para>A share consists of a directory to which access is being 
        given plus a description of the access rights which are granted 
        to the user of the service. Some housekeeping options are 
        also specifiable.</para>
        
        <para>Sections are either file share services (used by the 
        client as an extension of their native file systems) or 
        printable services (used by the client to access print services 
        on the host running the server).</para>
        
        <para>Sections may be designated <emphasis>guest</emphasis> services,
        in which case no password is required to access them. A specified 
        UNIX <emphasis>guest account</emphasis> is used to define access
        privileges in this case.</para>

        <para>Sections other than guest services will require a password 
        to access them. The client provides the username. As older clients 
        only provide passwords and not usernames, you may specify a list 
        of usernames to check against the password using the <quote>user =</quote>
        option in the share definition. For modern clients such as 
        Windows 95/98/ME/NT/2000, this should not be necessary.</para>

        <para>The access rights granted by the server are 
        masked by the access rights granted to the specified or guest 
        UNIX user by the host system. The server does not grant more
        access than the host system grants.</para>
        
        <para>The following sample section defines a file space share. 
        The user has write access to the path <filename moreinfo="none">/home/bar</filename>. 
        The share is accessed via the share name <quote>foo</quote>:</para>

<smbconfexample>
        <smbconfsection name="[foo]"/>
        <smbconfoption name="path">/home/bar</smbconfoption>
        <smbconfoption name="read only">read only = no</smbconfoption>
</smbconfexample>

        <para>The following sample section defines a printable share. 
        The share is read-only, but printable. That is, the only write 
        access permitted is via calls to open, write to and close a 
        spool file. The <emphasis>guest ok</emphasis> parameter means 
        access will be permitted as the default guest user (specified 
        elsewhere):</para>

<smbconfexample>
        <smbconfsection name="[aprinter]"/>
        <smbconfoption name="path">/usr/spool/public</smbconfoption>
        <smbconfoption name="read only">yes</smbconfoption>
        <smbconfoption name="printable">yes</smbconfoption>
        <smbconfoption name="guest ok">yes</smbconfoption>
</smbconfexample>
</refsect1>

<refsect1>
        <title>SPECIAL SECTIONS</title>
        
        <refsect2>
                <title>The [global] section</title>
                
                <para>Parameters in this section apply to the server 
                as a whole, or are defaults for sections that do not 
                specifically define certain items. See the notes
                under PARAMETERS for more information.</para>
        </refsect2>
        
        <refsect2 id="HOMESECT">
                <title>The [homes] section</title>
                
                <para>If a section called [homes] is included in the 
                configuration file, services connecting clients to their 
                home directories can be created on the fly by the server.</para>

                <para>When the connection request is made, the existing 
                sections are scanned. If a match is found, it is used. If no 
                match is found, the requested section name is treated as a 
                username and looked up in the local password file. If the 
                name exists and the correct password has been given, a share is 
                created by cloning the [homes] section.</para>
                
                <para>Some modifications are then made to the newly 
                created share:</para>
                
                <itemizedlist>
                <listitem><para>The share name is changed from homes to 
                the located username.</para></listitem>

                <listitem><para>If no path was given, the path is set to
                the user's home directory.</para></listitem>
                </itemizedlist>

                <para>If you decide to use a <emphasis>path =</emphasis> line 
                in your [homes] section, you may find it useful 
                to use the %S macro. For example :</para>

                <para><userinput moreinfo="none">path = /data/pchome/%S</userinput></para>

                <para>is useful if you have different home directories 
                for your PCs than for UNIX access.</para>

                <para>This is a fast and simple way to give a large number 
                of clients access to their home directories with a minimum 
                of fuss.</para>

                <para>A similar process occurs if the requested section 
                name is <quote>homes</quote>, except that the share name is not 
                changed to that of the requesting user. This method of using
                the [homes] section works well if different users share 
                a client PC.</para>
                
                <para>The [homes] section can specify all the parameters 
                a normal service section can specify, though some make more sense 
                than others. The following is a typical and suitable [homes]
                section:</para>

        <smbconfexample>
                <smbconfsection name="[homes]"/>
                <smbconfoption name="read only">no</smbconfoption>
        </smbconfexample>
        
                <para>An important point is that if guest access is specified 
                in the [homes] section, all home directories will be 
                visible to all clients <emphasis>without a password</emphasis>. 
                In the very unlikely event that this is actually desirable, it 
                is wise to also specify <emphasis>read only access</emphasis>.</para>

                <para>The <emphasis>browseable</emphasis> flag for 
                auto home directories will be inherited from the global browseable 
                flag, not the [homes] browseable flag. This is useful as 
                it means setting <emphasis>browseable = no</emphasis> in
                the [homes] section will hide the [homes] share but make
                any auto home directories visible.</para>
        </refsect2>

        <refsect2 id="PRINTERSSECT">
                <title>The [printers] section</title>
                
                <para>This section works like [homes], 
                but for printers.</para>

                <para>If a [printers] section occurs in the 
                configuration file, users are able to connect to any printer 
                specified in the local host's printcap file.</para>

                <para>When a connection request is made, the existing sections 
                are scanned. If a match is found, it is used. If no match is found, 
                but a [homes] section exists, it is used as described
                above. Otherwise, the requested section name is treated as a
                printer name and the appropriate printcap file is scanned to see 
                if the requested section name is a valid printer share name. If 
                a match is found, a new printer share is created by cloning 
                the [printers] section.</para>

                <para>A few modifications are then made to the newly created 
                share:</para>

                <itemizedlist>
                <listitem><para>The share name is set to the located printer 
                name</para></listitem>

                <listitem><para>If no printer name was given, the printer name 
                is set to the located printer name</para></listitem>

                <listitem><para>If the share does not permit guest access and 
                no username was given, the username is set to the located 
                printer name.</para></listitem>
                </itemizedlist>

                <para>The [printers] service MUST be 
                printable - if you specify otherwise, the server will refuse 
                to load the configuration file.</para>
                
                <para>Typically the path specified is that of a 
                world-writeable spool directory with the sticky bit set on 
                it. A typical [printers] entry looks like 
                this:</para>

        <smbconfexample>
                <smbconfsection name="[printers]"/>
                <smbconfoption name="path">/usr/spool/public</smbconfoption>
                <smbconfoption name="guest ok">yes</smbconfoption>
                <smbconfoption name="printable">yes</smbconfoption>
        </smbconfexample>

                <para>All aliases given for a printer in the printcap file 
                are legitimate printer names as far as the server is concerned. 
                If your printing subsystem doesn't work like that, you will have 
                to set up a pseudo-printcap. This is a file consisting of one or 
                more lines like this:</para>

                <programlisting>
alias|alias|alias|alias...    
                </programlisting>

                <para>Each alias should be an acceptable printer name for 
                your printing subsystem. In the [global] section, specify 
                the new file as your printcap.  The server will only recognize 
                names found in your pseudo-printcap, which of course can contain 
                whatever aliases you like. The same technique could be used 
                simply to limit access to a subset of your local printers.</para>

                <para>An alias, by the way, is defined as any component of the 
                first entry of a printcap record. Records are separated by newlines,
                components (if there are more than one) are separated by vertical 
                bar symbols (<quote>|</quote>).</para>
                
                <note><para>On SYSV systems which use lpstat to determine what 
                printers are defined on the system you may be able to use
                <quote>printcap name = lpstat</quote> to automatically obtain a list 
                of printers. See the <quote>printcap name</quote> option 
                for more details.</para></note>
        </refsect2>
</refsect1>

<refsect1>
        <title>PARAMETERS</title>

        <para>Parameters define the specific attributes of sections.</para>

        <para>Some parameters are specific to the [global] section
        (e.g., <emphasis>security</emphasis>).  Some parameters are usable 
        in all sections (e.g., <emphasis>create mode</emphasis>). All others 
        are permissible only in normal sections. For the purposes of the 
        following descriptions the [homes] and [printers]
        sections will be considered normal.  The letter <emphasis>G</emphasis> 
        in parentheses indicates that a parameter is specific to the
        [global] section. The letter <emphasis>S</emphasis>
        indicates that a parameter can be specified in a service specific
        section. All <emphasis>S</emphasis> parameters can also be specified in 
        the [global] section - in which case they will define
        the default behavior for all services.</para>

        <para>Parameters are arranged here in alphabetical order - this may 
        not create best bedfellows, but at least you can find them! Where
        there are synonyms, the preferred synonym is described, others refer 
        to the preferred synonym.</para>
</refsect1>

<refsect1>
        <title>VARIABLE SUBSTITUTIONS</title>

        <para>Many of the strings that are settable in the config file 
        can take substitutions. For example the option <quote>path =
        /tmp/%u</quote> is interpreted as <quote>path = 
        /tmp/john</quote> if the user connected with the username john.</para>

        <para>These substitutions are mostly noted in the descriptions below, 
        but there are some general substitutions which apply whenever they 
        might be relevant. These are:</para>

        <variablelist>
                <varlistentry>
                <term>%U</term>
                <listitem><para>session username (the username that the client 
                wanted, not necessarily the same as the one they got).</para></listitem>
                </varlistentry>
                
                <varlistentry>
                <term>%G</term>
                <listitem><para>primary group name of %U.</para></listitem>
                </varlistentry>

                <varlistentry>
                <term>%h</term>
                <listitem><para>the Internet hostname that Samba is running 
                on.</para></listitem>
                </varlistentry>

                <varlistentry>
                <term>%m</term>
                <listitem><para>the NetBIOS name of the client machine 
                (very useful).</para></listitem>
                </varlistentry>
                
                <varlistentry>
                <term>%L</term>
                <listitem><para>the NetBIOS name of the server. This allows you 
                to change your config based on what the client calls you. Your 
                server can have a <quote>dual personality</quote>.</para>

                <para>This parameter is not available when Samba listens
                on port 445, as clients no longer send this information.</para>
                </listitem>

                </varlistentry>
                
                <varlistentry>
                <term>%M</term>
                <listitem><para>the Internet name of the client machine.
                </para></listitem>
                </varlistentry>
                
                <varlistentry>
                <term>%R</term>
                <listitem><para>the selected protocol level after 
                protocol negotiation. It can be one of CORE, COREPLUS, 
                LANMAN1, LANMAN2 or NT1.</para></listitem>
                </varlistentry>

                <varlistentry>
                <term>%d</term>
                <listitem><para>the process id of the current server
                process.</para></listitem>
                </varlistentry>
                
                <varlistentry>
                <term>%a</term>
                <listitem><para>the architecture of the remote
                machine.  It currently recognizes Samba (<constant>Samba</constant>), 
                the Linux CIFS file system (<constant>CIFSFS</constant>), OS/2, (<constant>OS2</constant>),
                Windows for Workgroups (<constant>WfWg</constant>), Windows 9x/ME 
                (<constant>Win95</constant>), Windows NT (<constant>WinNT</constant>),
                Windows 2000 (<constant>Win2K</constant>), Windows XP (<constant>WinXP</constant>),
                and Windows 2003 (<constant>Win2K3</constant>).  Anything else will be known as 
                <constant>UNKNOWN</constant>.</para> 
                </varlistentry>
                
                <varlistentry>
                <term>%I</term>
                <listitem><para>the IP address of the client machine.</para>
                </listitem>
                </varlistentry>

                <varlistentry>
                <term>%i</term>
                <listitem><para>the local IP address to which a client connected.</para>
                </listitem>
                </varlistentry>

                <varlistentry>
                <term>%T</term>
                <listitem><para>the current date and time.</para></listitem>
                </varlistentry>

                <varlistentry>
                <term>%D</term>
                <listitem><para>name of the domain or workgroup of the current user.</para></listitem>
                </varlistentry>
                
                <varlistentry>
                <term>%$(<replaceable>envvar</replaceable>)</term>
                <listitem><para>the value of the environment variable
                <replaceable>envar</replaceable>.</para></listitem>
                </varlistentry>
        </variablelist>

        <para>The following substitutes apply only to some configuration options (only those 
        that are used when a connection has been established):</para>

        <variablelist>
                <varlistentry>
                <term>%S</term>
                <listitem><para>the name of the current service, if any.</para>
                </listitem>
                </varlistentry>
        
                <varlistentry>
                <term>%P</term>
                <listitem><para>the root directory of the current service, 
                if any.</para></listitem>
                </varlistentry>
        
                <varlistentry>
                <term>%u</term>
                <listitem><para>username of the current service, if any.</para>
                </listitem>
                </varlistentry>
        
                <varlistentry>
                <term>%g</term>
                <listitem><para>primary group name of %u.</para></listitem>
                </varlistentry>
        
                <varlistentry>
                <term>%H</term>
                <listitem><para>the home directory of the user given 
                by %u.</para></listitem>
                </varlistentry>

                <varlistentry>
                <term>%N</term>
                <listitem><para>the name of your NIS home directory server.  
                This is obtained from your NIS auto.map entry.  If you have 
                not compiled Samba with the <emphasis>--with-automount</emphasis> 
                option, this value will be the same as %L.</para>
                </listitem>
                </varlistentry>
        
                <varlistentry>
                <term>%p</term>
                <listitem><para>the path of the service's home directory, 
                obtained from your NIS auto.map entry. The NIS auto.map entry 
                is split up as <quote>%N:%p</quote>.</para></listitem>
                </varlistentry>
        </variablelist>
        
        <para>There are some quite creative things that can be done 
        with these substitutions and other <filename moreinfo="none">smb.conf</filename> options.</para>
</refsect1>

<refsect1 id="NAMEMANGLINGSECT">
        <title>NAME MANGLING</title>
        
        <para>Samba supports <quote>name mangling</quote> so that DOS and 
        Windows clients can use files that don't conform to the 8.3 format. 
        It can also be set to adjust the case of 8.3 format filenames.</para>

        <para>There are several options that control the way mangling is 
        performed, and they are grouped here rather than listed separately. 
        For the defaults look at the output of the testparm program. </para>

        <para>All of these options can be set separately for each service 
        (or globally, of course). </para>

        <para>The options are: </para>
        
        <variablelist>
        
        <varlistentry>
                <term>case sensitive = yes/no/auto</term>
                <listitem><para>controls whether filenames are case sensitive. If 
                they aren't, Samba must do a filename search and match on passed 
                names. The default setting of auto allows clients that support case
                sensitive filenames (Linux CIFSVFS and smbclient 3.0.5 and above currently)
                to tell the Samba server on a per-packet basis that they wish to access
                the file system in a case-sensitive manner (to support UNIX case sensitive
                semantics). No Windows or DOS system supports case-sensitive filename so
                setting this option to auto is that same as setting it to no for them.
                Default <emphasis>auto</emphasis>.</para></listitem>
                </varlistentry> 

                <varlistentry>
                <term>default case = upper/lower</term>
                <listitem><para>controls what the default case is for new 
                filenames. Default <emphasis>lower</emphasis>.</para></listitem>
                </varlistentry> 
        
                <varlistentry>
                <term>preserve case = yes/no</term>
                <listitem><para>controls whether new files are created with the 
                case that the client passes, or if they are forced to be the 
                <quote>default</quote> case. Default <emphasis>yes</emphasis>.
                </para></listitem>
                </varlistentry> 

                <varlistentry>
                <term>short preserve case = yes/no</term>
                <listitem><para>controls if new files which conform to 8.3 syntax,
                that is all in upper case and of suitable length, are created 
                upper case, or if they are forced to be the <quote>default</quote> 
                case. This option can be used with <quote>preserve case = yes</quote> 
                to permit long filenames to retain their case, while short names 
                are lowercased. Default <emphasis>yes</emphasis>.</para></listitem>
                </varlistentry> 
        </variablelist>
        
        <para>By default, Samba 3.0 has the same semantics as a Windows 
        NT server, in that it is case insensitive but case preserving.</para>
        
</refsect1>

<refsect1 id="VALIDATIONSECT">
        <title>NOTE ABOUT USERNAME/PASSWORD VALIDATION</title>

        <para>There are a number of ways in which a user can connect 
        to a service. The server uses the following steps in determining 
        if it will allow a connection to a specified service. If all the 
        steps fail, the connection request is rejected.  However, if one of the 
        steps succeeds, the following steps are not checked.</para>

        <para>If the service is marked <quote>guest only = yes</quote> and the
        server is running with share-level security (<quote>security = share</quote>,
        steps 1 to 5 are skipped.</para>


        <orderedlist continuation="restarts" inheritnum="ignore" numeration="arabic">
                <listitem><para>If the client has passed a username/password 
                pair and that username/password pair is validated by the UNIX 
                system's password programs, the connection is made as that 
                username. This includes the 
                \\server\service%<replaceable>username</replaceable> method of passing 
                a username.</para></listitem>

                <listitem><para>If the client has previously registered a username 
                with the system and now supplies a correct password for that 
                username, the connection is allowed.</para></listitem>
                
                <listitem><para>The client's NetBIOS name and any previously 
                used usernames are checked against the supplied password. If 
                they match, the connection is allowed as the corresponding 
                user.</para></listitem>
                
                <listitem><para>If the client has previously validated a
                username/password pair with the server and the client has passed 
                the validation token, that username is used. </para></listitem>

                <listitem><para>If a <quote>user = </quote> field is given in the
                <filename moreinfo="none">smb.conf</filename> file for the service and the client 
                has supplied a password, and that password matches (according to 
                the UNIX system's password checking) with one of the usernames 
                from the <quote>user =</quote> field, the connection is made as 
                the username in the <quote>user =</quote> line. If one 
                of the usernames in the <quote>user =</quote> list begins with a
                <quote>@</quote>, that name expands to a list of names in 
                the group of the same name.</para></listitem>

                <listitem><para>If the service is a guest service, a 
                connection is made as the username given in the <quote>guest 
                account =</quote> for the service, irrespective of the 
                supplied password.</para></listitem>
        </orderedlist>

</refsect1>

<refsect1>
        <title>EXPLANATION OF EACH PARAMETER</title>
        
        <xi:include href="../smbdotconf/parameters.all.xml" parse="xml"/>

</refsect1>

<refsect1>
        <title>WARNINGS</title>
        
        <para>Although the configuration file permits service names 
        to contain spaces, your client software may not. Spaces will 
        be ignored in comparisons anyway, so it shouldn't be a 
        problem - but be aware of the possibility.</para>

        <para>On a similar note, many clients - especially DOS clients - 
        limit service names to eight characters. <citerefentry><refentrytitle>smbd</refentrytitle>
        <manvolnum>8</manvolnum></citerefentry> has no such limitation, but attempts to connect from such 
        clients will fail if they truncate the service names.  For this reason 
        you should probably keep your service names down to eight characters 
        in length.</para>

        <para>Use of the [homes] and [printers] special sections make life 
        for an administrator easy, but the various combinations of default 
        attributes can be tricky. Take extreme care when designing these 
        sections. In particular, ensure that the permissions on spool 
        directories are correct.</para>
</refsect1>

<refsect1>
        <title>VERSION</title>

        <para>This man page is correct for version 3.0 of the Samba suite.</para>
</refsect1>

<refsect1>
        <title>SEE ALSO</title>
        <para>
        <citerefentry><refentrytitle>samba</refentrytitle>
        <manvolnum>7</manvolnum></citerefentry>, <citerefentry><refentrytitle>smbpasswd</refentrytitle>
        <manvolnum>8</manvolnum></citerefentry>, <citerefentry><refentrytitle>swat</refentrytitle>
        <manvolnum>8</manvolnum></citerefentry>, <citerefentry><refentrytitle>smbd</refentrytitle>
        <manvolnum>8</manvolnum></citerefentry>, <citerefentry><refentrytitle>nmbd</refentrytitle>
        <manvolnum>8</manvolnum></citerefentry>, <citerefentry><refentrytitle>smbclient</refentrytitle>
        <manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>nmblookup</refentrytitle>
        <manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>testparm</refentrytitle>
        <manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>testprns</refentrytitle>
        <manvolnum>1</manvolnum></citerefentry>.</para>
</refsect1>

<refsect1>
        <title>AUTHOR</title>
        
        <para>The original Samba software and related utilities 
        were created by Andrew Tridgell. Samba is now developed
        by the Samba Team as an Open Source project similar 
        to the way the Linux kernel is developed.</para>
        
        <para>The original Samba man pages were written by Karl Auer. 
        The man page sources were converted to YODL format (another 
        excellent piece of Open Source software, available at <ulink noescape="1" url="ftp://ftp.icce.rug.nl/pub/unix/">
        ftp://ftp.icce.rug.nl/pub/unix/</ulink>) and updated for the Samba 2.0 
        release by Jeremy Allison.  The conversion to DocBook for 
        Samba 2.2 was done by Gerald Carter. The conversion to DocBook XML 4.2
        for Samba 3.0 was done by Alexander Bokovoy.</para>
</refsect1>

</refentry>