[hcoop/debian/openafs.git] / doc / xml / AdminGuide / auagd023.xml

<?xml version="1.0" encoding="UTF-8"?>
<appendix id="HDRCOMMANDS">
  <title>Using AFS Commands</title>

  <para>This section describes the components of AFS commands and how to make entering commands more efficient by using shortened
  forms. It has the following sections: <simplelist>
      <member><link linkend="HDRWQ613">AFS Command Syntax</link></member>

      <member><link linkend="HDRWQ614">Rules for Entering AFS Commands</link></member>

      <member><link linkend="HDRWQ615">Rules for Using Abbreviations and Aliases</link></member>

      <member><link linkend="HDRWQ616">Displaying Online Help for AFS Commands</link></member>
    </simplelist></para>

  <sect1 id="HDRWQ613">
    <title>AFS Command Syntax</title>

    <para>AFS commands that belong to suites have the following structure:</para>

    <programlisting><emphasis role="bold">command_suite operation_code</emphasis><emphasis role="bold">-switch</emphasis> <replaceable>&lt;value&gt;</replaceable>[+]  [<emphasis
        role="bold">-flag</emphasis>]
</programlisting>

    <sect2 id="Header_691">
      <title>Command Names</title>

      <para>Together, the <emphasis role="bold">command_suite</emphasis> and <emphasis role="bold">operation_code</emphasis> make up
      the <emphasis>command name</emphasis>.</para>

      <para>The <emphasis role="bold">command_suite</emphasis> specifies the group of related commands to which the command belongs,
      and indicates which command interpreter and server process perform the command. AFS has several command suites, including
      <emphasis role="bold">bos</emphasis>, <emphasis role="bold">fs</emphasis>, <emphasis role="bold">kas</emphasis>,
      <emphasis role="bold">pts</emphasis>, <emphasis role="bold">scout</emphasis>, <emphasis
      role="bold">uss</emphasis> and <emphasis role="bold">vos</emphasis>. Some of these suites have an interactive mode in which
      the issuer omits the <emphasis role="bold">command_suite</emphasis> portion of the command name.</para>

      <para>The <emphasis role="bold">operation_code</emphasis> tells the command interpreter and server process which action to
      perform. Most command suites include several operation codes. The <emphasis>OpenAFS Administration Reference</emphasis>
      describes each operation code in detail, and the <emphasis>OpenAFS Administration Guide</emphasis> describes how to use them
      in the context of performing administrative tasks.</para>

      <para>Several AFS commands do not belong to a suite and so their names do not have a <emphasis
      role="bold">command_suite</emphasis> portion. Their structure is otherwise similar to the commands in the suites.</para>
    </sect2>

    <sect2 id="Header_692">
      <title>Options</title>

      <para>The term <emphasis>option</emphasis> refers to both arguments and flags, which are described in the following
      sections.</para>
    </sect2>

    <sect2 id="Header_693">
      <title>Arguments</title>

      <para>One or more arguments can follow the command name. Arguments specify the entities on which to act while performing the
      command (for example, which server machine, server process, or file). To minimize the potential for error, provide a command's
      arguments in the order prescribed in its syntax definition.</para>

      <para>Each argument has two parts, which appear in the indicated order: <itemizedlist>
          <listitem>
            <para>The <emphasis>switch</emphasis> specifies the argument's type and is preceded by a hyphen ( <emphasis
            role="bold">-</emphasis> ). For instance, the switch <emphasis role="bold">-server</emphasis> usually indicates that the
            argument names a server machine. Switches can often be omitted, subject to the rules outlined in <link
            linkend="HDRNOSWITCH">Conditions for Omitting Switches</link>.</para>
          </listitem>

          <listitem>
            <para>The <emphasis>value</emphasis> names a particular entity of the type specified by the preceding switch. For
            example, the proper value for a <emphasis role="bold">-server</emphasis> switch is a server machine name like <emphasis
            role="bold">fs3.example.com</emphasis>. Unlike switches (which have a required form), values vary depending on what the
            issuer wants to accomplish. Values appear surrounded by angle brackets (<emphasis role="bold">&lt; &gt;</emphasis>) in
            command descriptions and the online help to show that they are user-supplied variable information.</para>
          </listitem>
        </itemizedlist></para>

      <para>Some arguments accept multiple values, as indicated by trailing plus sign ( <emphasis role="bold">+</emphasis> ) in the
      command descriptions and online help. How many of a command's arguments take multiple values, and their ordering with respect
      to other arguments, determine when it is acceptable to omit switches. See <link linkend="HDRNOSWITCH">Conditions for Omitting
      Switches</link>.</para>

      <para>Some commands have optional as well as required arguments; the command descriptions and online help show optional
      arguments in square brackets ([ ]).</para>
    </sect2>

    <sect2 id="Header_694">
      <title>Flags</title>

      <para>Some commands have one or more flags, which specify the manner in which the command interpreter and server process
      perform the command, or what kind of output it produces. Flags are preceded by hyphens like switches, but they take no values.
      Although the command descriptions and online help generally list a command's flags after its arguments, there is no prescribed
      order for flags. They can appear anywhere on the command line following the operation code, except in between the parts of an
      argument. Flags are always optional.</para>
    </sect2>

    <sect2 id="HDRCOMMAND-EX">
      <title>An Example Command</title>

      <para>The following example illustrates the different parts of a command that belongs to an AFS command suite.</para>

      <programlisting>
   % <emphasis role="bold">bos getdate -server fs1.example.com -file ptserver kaserver</emphasis>
</programlisting>

      <para>where <itemizedlist>
          <listitem>
            <para><emphasis role="bold">bos</emphasis> is the command suite. The BOS Server executes most of the commands in this
            suite.</para>
          </listitem>

          <listitem>
            <para><emphasis role="bold">getdate</emphasis> is the operation code. It tells the BOS Server on the specified server
            machine (in this case <emphasis role="bold">fs1.example.com</emphasis>) to report the modification dates of binary files in
            the local <emphasis role="bold">/usr/afs/bin</emphasis> directory.</para>
          </listitem>

          <listitem>
            <para><emphasis role="bold">-server fs1.example.com</emphasis> is one argument, with <emphasis
            role="bold">-server</emphasis> as the switch and <emphasis role="bold">fs1.example.com</emphasis> as the value. This
            argument specifies the server machine on which BOS Server is to collect and report binary dates.</para>
          </listitem>

          <listitem>
            <para><emphasis role="bold">-file ptserver kaserver</emphasis> is an argument that takes multiple values. The switch is
            <emphasis role="bold">-file</emphasis> and the values are <emphasis role="bold">ptserver</emphasis> and <emphasis
            role="bold">kaserver</emphasis>. This argument tells the BOS Server to report the modification dates on the files
            <emphasis role="bold">/usr/afs/bin/kaserver</emphasis> and <emphasis
            role="bold">/usr/afs/bin/ptserver</emphasis>.</para>
          </listitem>
        </itemizedlist></para>
    </sect2>

    <sect2 id="HDRWQ614">
      <title>Rules for Entering AFS Commands</title>

      <para>Enter each AFS command on a single line (press <emphasis role="bold">&lt;Return&gt;</emphasis> only at the end of the
      command). Some commands in this document appear broken across multiple lines, but that is for legibility only.</para>

      <para>Use a space to separate each element on a command line from its neighbors. Spaces rather than commas also separate
      multiple values of an argument.</para>

      <para>In many cases, the issuer of a command can reduce the amount of typing necessary by using one or both of the following
      methods: <itemizedlist>
          <listitem>
            <para>Omitting switches</para>
          </listitem>

          <listitem>
            <para>Using accepted abbreviations for operation codes, switches (if they are included at all), and some types of
            values</para>
          </listitem>
        </itemizedlist></para>

      <para>The following sections explain the conditions for omitting or shortening parts of the command line. It is always
      acceptable to type a command in full, with all of its switches and no abbreviations.</para>

      <sect3 id="HDRNOSWITCH">
        <title>Conditions for Omitting Switches</title>

        <para>It is always acceptable to type the switch part of an argument, but in many cases it is not necessary. Specifically,
        switches can be omitted if the following conditions are met. <itemizedlist>
            <listitem>
              <para>All of the command's required arguments appear in the order prescribed by the syntax statement</para>
            </listitem>

            <listitem>
              <para>No switch is provided for any argument</para>
            </listitem>

            <listitem>
              <para>There is only one value for each argument (but note the important exception discussed in the following
              paragraph)</para>
            </listitem>
          </itemizedlist></para>

        <para>Omitting switches is possible only because there is a prescribed order for each command's arguments. When the issuer
        does not include switches, the command interpreter relies instead on the order of arguments; it assumes that the first
        element after the operation code is the command's first argument, the next element is the command's second argument, and so
        on. The important exception is when a command's final required argument accepts multiple values. In this case, the command
        interpreter assumes that the issuer has correctly provided one value for each argument up through the final one, so any
        additional values at the end belong to the final argument.</para>

        <para>The following list describes the rules for omitting switches from the opposite perspective: an argument's switch must
        be provided when any of the following conditions apply. <itemizedlist>
            <listitem>
              <para>The command's arguments do not appear in the prescribed order</para>
            </listitem>

            <listitem>
              <para>An optional argument is omitted but a subsequent optional argument is provided</para>
            </listitem>

            <listitem>
              <para>A switch is provided for a preceding argument</para>
            </listitem>

            <listitem>
              <para>More than one value is supplied for a preceding argument (which must take multiple values, of course); without a
              switch on the current argument, the command interpreter assumes that the current argument is another value for the
              preceding argument</para>
            </listitem>
          </itemizedlist></para>
      </sect3>

      <sect3 id="Header_698">
        <title>An Example of Omitting Switches</title>

        <para>Consider again the example command from <link linkend="HDRCOMMAND-EX">An Example Command</link>.</para>

        <programlisting>
   % <emphasis role="bold">bos getdate -server fs1.example.com -file ptserver kaserver</emphasis>
</programlisting>

        <para>This command has two required arguments: the server machine name (identified by the <emphasis
        role="bold">-server</emphasis> switch) and binary file name (identified by the <emphasis role="bold">-file</emphasis>
        switch). The second argument accepts multiple values. By complying with all three conditions, the issuer can omit the
        switches:</para>

        <programlisting>
   % <emphasis role="bold">bos getdate fs1.example.com ptserver kaserver</emphasis>
</programlisting>

        <para>Because there are no switches, the <emphasis role="bold">bos</emphasis> command interpreter relies on the order of
        arguments. It assumes that the first element following the operation code, <emphasis role="bold">fs1.example.com</emphasis>, is
        the server machine name, and that the next argument, <emphasis role="bold">ptserver</emphasis>, is a binary file name. Then,
        because the command's second (and last) argument accepts multiple values, the command interpreter correctly interprets
        <emphasis role="bold">kaserver</emphasis> as an additional value for it.</para>

        <para>On the other hand, the following is not acceptable because it violates the first two conditions in <link
        linkend="HDRNOSWITCH">Conditions for Omitting Switches</link>: even though there is only one value per argument, the
        arguments do not appear in the prescribed order, and a switch is provided for one argument but not the other.</para>

        <programlisting>
   % <emphasis role="bold">bos getdate ptserver -server fs1.example.com</emphasis>
</programlisting>
      </sect3>
    </sect2>

    <sect2 id="HDRWQ615">
      <title>Rules for Using Abbreviations and Aliases</title>

      <para>This section explains how to abbreviate operation codes, option names, server machine names, partition names, and cell
      names. It is not possible to abbreviate other types of values.</para>

      <sect3 id="Header_700">
        <title>Abbreviating Operation Codes</title>

        <para>It is acceptable to abbreviate an operation code to the shortest form that still distinguishes it from the other
        operation codes in its suite.</para>

        <para>For example, it is acceptable to shorten <emphasis role="bold">bos install</emphasis> to <emphasis role="bold">bos
        i</emphasis> because there are no other operation codes in the <emphasis role="bold">bos</emphasis> command suite that begin
        with the letter <emphasis role="bold">i</emphasis>. In contrast, there are several <emphasis role="bold">bos</emphasis>
        operation codes that start with the letter <emphasis role="bold">s</emphasis>, so the abbreviations must be longer to remain
        unambiguous: <simplelist>
            <member><emphasis role="bold">bos sa</emphasis> for <emphasis role="bold">bos salvage</emphasis></member>

            <member><emphasis role="bold">bos seta</emphasis> for <emphasis role="bold">bos setauth</emphasis></member>

            <member><emphasis role="bold">bos setc</emphasis> for <emphasis role="bold">bos setcellname</emphasis></member>

            <member><emphasis role="bold">bos setr</emphasis> for <emphasis role="bold">bos setrestart</emphasis></member>

            <member><emphasis role="bold">bos sh</emphasis> for <emphasis role="bold">bos shutdown</emphasis></member>

            <member><emphasis role="bold">bos start</emphasis> for <emphasis role="bold">bos start</emphasis></member>

            <member><emphasis role="bold">bos startu</emphasis> for <emphasis role="bold">bos startup</emphasis></member>

            <member><emphasis role="bold">bos stat</emphasis> for <emphasis role="bold">bos status</emphasis></member>

            <member><emphasis role="bold">bos sto</emphasis> for <emphasis role="bold">bos stop</emphasis></member>
          </simplelist></para>

        <para>In addition to abbreviations, some operation codes have an <emphasis>alias</emphasis>, a short form that is not
        derived by abbreviating the operation code to its shortest unambiguous form. For example, the alias for the <emphasis
        role="bold">fs setacl</emphasis> command is <emphasis role="bold">fs sa</emphasis>, whereas the shortest unambiguous
        abbreviation is <emphasis role="bold">fs seta</emphasis>.</para>

        <para>There are two usual reasons an operation code has an alias: <itemizedlist>
            <listitem>
              <para>Because the command is frequently issued, it is convenient to have a form shorter than the one derived by
              abbreviating. The <emphasis role="bold">fs setacl</emphasis> command is an example.</para>
            </listitem>

            <listitem>
              <para>Because the command's name has changed, but users of previous versions of AFS know the former name. For example,
              <emphasis role="bold">bos listhosts</emphasis> has the alias <emphasis role="bold">bos getcell</emphasis>, its former
              name. It is acceptable to abbreviate aliases to their shortest unambiguous form (for example, <emphasis
              role="bold">bos getcell</emphasis> to <emphasis role="bold">bos getc</emphasis>).</para>
            </listitem>
          </itemizedlist></para>

        <para>Even if an operation code has an alias, it is still acceptable to use the shortest unambiguous form. Thus, the
        <emphasis role="bold">fs setacl</emphasis> command has three acceptable forms: <emphasis role="bold">fs setacl</emphasis>
        (the full form), <emphasis role="bold">fs seta</emphasis> (the shortest abbreviation), and <emphasis role="bold">fs
        sa</emphasis> (the alias).</para>
      </sect3>

      <sect3 id="Header_701">
        <title>Abbreviating Switches and Flags</title>

        <para>It is acceptable to shorten a switch or flag to the shortest form that distinguishes it from the other switches and
        flags for its operation code. It is often possible to omit switches entirely, subject to the conditions listed in <link
        linkend="HDRNOSWITCH">Conditions for Omitting Switches</link>.</para>
      </sect3>

      <sect3 id="HDRFMSABBREV">
        <title>Abbreviating Server Machine Names</title>

        <para>AFS server machines must have fully-qualified Internet-style host names (for example, <emphasis
        role="bold">fs1.example.com</emphasis>), but it is not always necessary to type the full name on the command line. AFS commands
        accept unambiguous shortened forms, but depend on the cell's name service (such as the Domain Name Service) or a local host
        table to resolve a shortened name to the fully-qualified equivalent when the command is issued.</para>

        <para>Most commands also accept the dotted decimal form of the machine's IP address as an identifier.</para>
      </sect3>

      <sect3 id="HDRPARTABBREV">
        <title>Abbreviating Partition Names</title>

        <para>Partitions that house AFS volumes must have names of the form <emphasis
        role="bold">/vicep</emphasis><replaceable>x</replaceable> or <emphasis
        role="bold">/vicep</emphasis><replaceable>xx</replaceable>, where the variable final portion is one or two lowercase
        letters. By convention, the first server partition created on a file server machine is called <emphasis
        role="bold">/vicepa</emphasis>, the second <emphasis role="bold">/vicepb</emphasis>, and so on. The <emphasis>OpenAFS Quick
        Beginnings</emphasis> explains how to configure and name a file server machine's partitions in preparation for storing AFS
        volumes on them.</para>

        <para>When issuing AFS commands, you can abbreviate a partition name using any of the following forms:</para>

        <programlisting>
<emphasis role="bold">/vicepa</emphasis>     =     <emphasis role="bold">vicepa</emphasis>      =      <emphasis role="bold">a</emphasis>      =      <emphasis
            role="bold">0</emphasis>
<emphasis role="bold">/vicepb</emphasis>     =     <emphasis role="bold">vicepb</emphasis>      =      <emphasis role="bold">b</emphasis>      =      <emphasis
            role="bold">1</emphasis>
</programlisting>

        <para>After <emphasis role="bold">/vicepz</emphasis> (for which the index is 25) comes</para>

        <programlisting>
<emphasis role="bold">/vicepaa</emphasis>    =     <emphasis role="bold">vicepaa</emphasis>     =      <emphasis role="bold">aa</emphasis>     =      <emphasis
            role="bold">26</emphasis>
<emphasis role="bold">/vicepab</emphasis>    =     <emphasis role="bold">vicepab</emphasis>     =      <emphasis role="bold">ab</emphasis>     =      <emphasis
            role="bold">27</emphasis>
</programlisting>

        <para>and so on through</para>

        <programlisting>
<emphasis role="bold">/vicepiv</emphasis>    =     <emphasis role="bold">vicepiv</emphasis>     =      <emphasis role="bold">iv</emphasis>     =      <emphasis
            role="bold">255</emphasis>
</programlisting>
      </sect3>

      <sect3 id="HDRCELLABBREV">
        <title>Abbreviating Cell Names</title>

        <para>A cell's full name usually matches its Internet domain name (such as <emphasis role="bold">example.org</emphasis> for
        the Example Organization or <emphasis role="bold">example.com</emphasis> for Example Corporation). Some AFS commands accept unambiguous
        shortened forms, usually with respect to the local <emphasis role="bold">/usr/vice/etc/CellServDB file</emphasis> but
        sometimes depending on the ability of the local name service to resolve the corresponding domain name.</para>
      </sect3>
    </sect2>

    <sect2 id="HDRWQ616">
      <title>Displaying Online Help for AFS Commands</title>

      <para>To display online help for AFS commands that belong to suites, use the <emphasis role="bold">help</emphasis> and
      <emphasis role="bold">apropos</emphasis> operation codes. A <emphasis role="bold">-help</emphasis> flag is also available on
      every almost every AFS command.</para>

      <para>The online help entry for a command consists of two or three lines: <itemizedlist>
          <listitem>
            <para>The first line names the command and briefly describes what it does</para>
          </listitem>

          <listitem>
            <para>If the command has aliases, they appear on the next line</para>
          </listitem>

          <listitem>
            <para>The final line, which begins with the string <computeroutput>Usage:</computeroutput>, lists the command's options
            in the prescribed order; online help entries use the same typographical symbols (brackets and so on) as this
            documentation.</para>
          </listitem>
        </itemizedlist></para>

      <para>If no operation code is specified, the <emphasis role="bold">help</emphasis> operation code displays the first line
      (short description) for every operation code in the suite:</para>

      <programlisting>
   % <replaceable>command_suite</replaceable> <emphasis role="bold">help</emphasis>
</programlisting>

      <para>If the issuer specifies one or more operation codes, the <emphasis role="bold">help</emphasis> operation code displays
      each command's complete online entry (short description, alias if any, and syntax):</para>

      <programlisting>
   % <replaceable>command_suite</replaceable> <emphasis role="bold">help</emphasis> <replaceable>operation_code</replaceable>+
</programlisting>

      <para>The <emphasis role="bold">-help</emphasis> flag displays a command's syntax but not the short description or
      alias:</para>

      <programlisting>
   % <replaceable>command_name</replaceable> <emphasis role="bold">-help</emphasis>
</programlisting>

      <para>The <emphasis role="bold">apropos</emphasis> operation code displays the short description of any command in a suite
      whose operation code or short description includes the specified keyword:</para>

      <programlisting>
   % <replaceable>command_suite</replaceable> <emphasis role="bold">apropos</emphasis> <replaceable>"&lt;help string&gt;"</replaceable>
</programlisting>

      <para>The following example command displays the complete online help entry for the <emphasis role="bold">fs setacl</emphasis>
      command:</para>

      <programlisting>
   % <emphasis role="bold">fs help setacl</emphasis>
   fs setacl: set access control list
   aliases: sa
   Usage: fs setacl -dir &lt;<replaceable>directory</replaceable>&gt;+ -acl &lt;<replaceable>access list entries</replaceable>&gt;+
   [-clear] [-negative] [-id] [-if] [-help]
</programlisting>

      <para>To see only the syntax statement, use the <emphasis role="bold">-help</emphasis> flag:</para>

      <programlisting>
   % <emphasis role="bold">fs setacl -help</emphasis>
   Usage: fs setacl -dir &lt;<replaceable>directory</replaceable>&gt;+ -acl &lt;<replaceable>access list entries</replaceable>&gt;+
   [-clear] [-negative] [-id] [-if] [-help]
</programlisting>

      <para>In the following example, a user wants to display the quota for her home volume. She knows that the relevant command
      belongs to the <emphasis role="bold">fs</emphasis> suite, but cannot remember the operation code. She uses <emphasis
      role="bold">quota</emphasis> as the keyword:</para>

      <programlisting>
   % <emphasis role="bold">fs apropos quota</emphasis>
   listquota: list volume quota
   quota: show volume quota usage
   setquota: set volume quota
</programlisting>

      <para>The following illustrates the error message that results if no command name or short description contains the
      keyword:</para>

      <programlisting>
   % <emphasis role="bold">fs apropos "list quota"</emphasis>
   Sorry, no commands found
</programlisting>
    </sect2>
  </sect1>
</appendix>