shadow/man/faillog.8.xml

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<refentry id='faillog.8'>
  <!--  $Id$ -->
  <refmeta>
    <refentrytitle>faillog</refentrytitle>
    <manvolnum>8</manvolnum>
    <refmiscinfo class="sectdesc">System Management Commands</refmiscinfo>
  </refmeta>
  <refnamediv id='name'>
    <refname>faillog</refname>
    <refpurpose>display faillog records or set login failure limits</refpurpose>
  </refnamediv>

  <refsynopsisdiv id='synopsis'>
    <cmdsynopsis>
      <command>faillog</command>
      <arg choice='opt'>
	<replaceable>options</replaceable>
      </arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1 id='description'>
    <title>DESCRIPTION</title>
    <para>
      <command>faillog</command> formats the contents of the failure log
      from <filename>/var/log/faillog</filename> database. It also can be
      used for maintains failure counters and limits. Run
      <command>faillog</command> without arguments display only list of user
      faillog records who have ever had a login failure.
    </para>
  </refsect1>

  <refsect1 id='options'>
    <title>OPTIONS</title>
    <para>
      The options which apply to the <command>faillog</command> command
      are:
    </para>
    <variablelist remap='IP'>
      <varlistentry>
	<term><option>-a</option>, <option>--all</option></term>
	<listitem>
	  <para>
	    Display (or act on) faillog records for all users having an
	    entry in the <filename>faillog</filename> database.
	  </para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term><option>-h</option>, <option>--help</option></term>
	<listitem>
	  <para>Display help message and exit.</para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term>
	  <option>-l</option>, <option>--lock-time</option>
	  <replaceable>SEC</replaceable>
	</term>
	<listitem>
	  <para>
	    Lock account to <replaceable>SEC</replaceable>
	    seconds after failed login.
	  </para>
	  <para>
	    Write access to <filename>/var/log/faillog</filename>
	    is required for this option.
	  </para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term>
	  <option>-m</option>, <option>--maximum</option>
	  <replaceable>MAX</replaceable>
	</term>
	<listitem>
	  <para>
	    Set maximum number of login failures after the account is
	    disabled to <replaceable>MAX</replaceable>.
	  </para>
	  <para>
	    Selecting a
	    <replaceable>MAX</replaceable> value of 0 has the effect of not
	    placing a limit on the number of failed logins.
	  </para>
	  <para>
	    The maximum
	    failure count should always be 0 for <emphasis>root</emphasis>
	    to prevent a denial of services attack against the system.
	  </para>
	  <para>
	    Write access to <filename>/var/log/faillog</filename>
	    is required for this option.
	  </para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term><option>-r</option>, <option>--reset</option></term>
	<listitem>
	  <para>
	    Reset the counters of login failures or one record if used with
	    the <option>-u</option> <replaceable>LOGIN</replaceable>
	    option.
	  </para>
	  <para>
	    Write access to <filename>/var/log/faillog</filename>
	    is required for this option.
	  </para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term><option>-t</option>, <option>--time</option>
	<replaceable>DAYS</replaceable>
	</term>
	<listitem>
	  <para>
	    Display faillog records more recent than
	    <replaceable>DAYS</replaceable>.
	  </para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term>
	  <option>-u</option>, <option>--user</option>
	  <replaceable>LOGIN</replaceable>|<replaceable>RANGE</replaceable>
	</term>
	<listitem>
	  <para>
	    Display faillog record or maintains failure counters and limits
	    (if used with <option>-l</option>, <option>-m</option> or
	    <option>-r</option> options) only for the specified user(s).
	  </para>
	  <para>
	    The users can be specified by a login name, a numerical user
	    ID, or a <replaceable>RANGE</replaceable> of users.  This
	    <replaceable>RANGE</replaceable> of users can be specified
	    with a min and max values
	    (<replaceable>UID_MIN-UID_MAX</replaceable>), a max value
	    (<replaceable>-UID_MAX</replaceable>), or a min value
	    (<replaceable>UID_MIN-</replaceable>).
	  </para>
	</listitem>
      </varlistentry>
    </variablelist>

    <para>
      When none of the <option>-l</option>, <option>-m</option>, or
      <option>-r</option> options are used, <command>faillog</command>
      displays the faillog record of the specified user(s).
    </para>
    <para>
      NOTE: in display mode, only the records of users which currently
      exist in the system are displayed.  In the other modes (when the
      <option>-l</option>, <option>-m</option>, or <option>-r</option>
      options are used), the records of the user, or the range of users,
      or all the users that may have an entry in the faillog database will
      be changed.  This is useful to reset records of users that have been
      deleted or set a policy in advance for a range of users.
    </para>
  </refsect1>

  <refsect1 id='caveats'>
    <title>CAVEATS</title>
    <para>
      <command>faillog</command> only prints out users with no successful
      login since the last failure. To print out a user who has had a
      successful login since their last failure, you must explicitly request
      the user with the <option>-u</option> flag, or print out all users
      with the <option>-a</option> flag.
    </para>
  </refsect1>

  <refsect1 id='files'>
    <title>FILES</title>
    <variablelist>
      <varlistentry>
	<term><filename>/var/log/faillog</filename></term>
	<listitem>
	  <para>Failure logging file.</para>
	</listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1 id='see_also'>
    <title>SEE ALSO</title>
    <para>
      <citerefentry>
	<refentrytitle>login</refentrytitle><manvolnum>1</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>faillog</refentrytitle><manvolnum>5</manvolnum>
      </citerefentry>.
    </para>
  </refsect1>
</refentry>