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  <articleinfo>
    <title>Óýíäåóç ÌÝóù Ôçëåöþíïõ êáé Ôåß÷ïò Ðñïóôáóßáò óôï FreeBSD</title>

    <authorgroup>
      <author>
        <firstname>Marc</firstname>
        <surname>Silver</surname>

        <affiliation>
          <address><email>marcs@draenor.org</email></address>
        </affiliation>
      </author>
    </authorgroup>

    <pubdate>$FreeBSD$</pubdate>

    <legalnotice id="trademarks" role="trademarks">
      &tm-attrib.freebsd;
      &tm-attrib.general;
    </legalnotice>

    <abstract>
      <para>Áõôü ôï Üñèñï ðåñéãñÜöåé ðùò ìðïñåßôå íá ñõèìßóåôå Ýíá ôåß÷ïò ðñïóôáóßáò (firewall)
        ÷ñçóéìïðïéþíôáò ìéá PPP óýíäåóç ìÝóù ôçëåöþíïõ óôï FreeBSD ìå ôï IPFW.
        Ðéï óõãêåêñéìÝíá, ðåñéãñÜöåé ôç ñýèìéóç åíüò ôåß÷ïõò ðñïóôáóßáò óå ìéá óýíäåóç ìÝóù ôçëåöþíïõ ðïõ
        Ý÷åé äõíáìéêÞ IP äéåýèõíóç.  Áõôü ôï êåßìåíï äåí áó÷ïëåßôáé ìå ôï ðùò
        èá ñõèìßóåôå ôçí áñ÷éêÞ óáò óýíäåóç ìÝóù PPP.  Ãéá ðåñéóóüôåñåò
	ðëçñïöïñßåò ó÷åôéêÜ ìå ôéò ñõèìßóåéò ìéáò óýíäåóçò ìÝóù PPP äåßôå ôç
	óåëßäá âïÞèåéáò &man.ppp.8;.</para>
    </abstract>
  </articleinfo>

  <sect1 id="preface">
    <title>Ðñüëïãïò</title>

     <para>Áõôü ôï êåßìåíï ðåñéãñÜöåé ôçí äéáäéêáóßá ðïõ ÷ñåéÜæåôáé ãéá íá
       ñõèìßóåôå Ýíá ôåß÷ïò ðñïóôáóßáò óôï FreeBSD üôáí ç IP äéåýèõíóç äßíåôáé äõíáìéêÜ
       áðü ôïí ISP óáò.  Ðáñüëï ðïõ Ý÷ù ðñïóðáèÞóåé íá êÜíù áõôü ôï êåßìåíï
       üóï ôï äõíáôüí ðéï ðëÞñåò êáé óùóôü, åßóôå åõðñüóäåêôïé íá óôåßëåôå ôéò
       äéïñèþóåéò, ôá ó÷üëéá Þ ôéò ðñïôÜóåéò óáò óôç äéåýèõíóç ôïõ óõããñáöÝá:
       <email>marcs@draenor.org</email>.</para>
   </sect1>

  <sect1 id="kernel">
    <title>ÐáñÜìåôñïé ôïõ ðõñÞíá</title>

    <para>Ãéá íá ìðïñÝóåôå íá ÷ñçóéìïðïéÞóåôå ôï IPFW, ðñÝðåé íá åíóùìáôþóåôå
      ôçí ó÷åôéêÞ õðïóôÞñéîç óôïí ðõñÞíá óáò.  Ãéá ðåñéóóüôåñåò ðëçñïöïñßåò
      ó÷åôéêÜ ìå ôç ìåôáãëþôôéóç ôïõ ðõñÞíá, äåßôå ôï <ulink
        url="&url.books.handbook;/kernelconfig.html">ôìÞìá
      ñõèìßóåùí ôïõ ðõñÞíá óôï Åã÷åéñßäéï</ulink>.  Èá ðñÝðåé íá ðñïóèÝóåôå
      ôéò ðáñáêÜôù åðéëïãÝò óôéò ñõèìßóåéò ôïõ ðõñÞíá óáò ãéá íá
      åíåñãïðïéÞóåôå ôçí õðïóôÞñéîç ãéá ôï IPFW:</para>

    <variablelist>
      <varlistentry>
        <term><literal>options IPFIREWALL</literal></term>

        <listitem>
          <para>Åíåñãïðïéåß ôïí êþäéêá ôåß÷ïõò ðñïóôáóßáò ôïõ ðõñÞíá.</para>
	  <note>
	    <para>Áõôü ôï êåßìåíï èåùñåß üôé Ý÷åôå åãêáôáóôÞóåé ôçí Ýêäïóç 5.X
	    ôïõ FreeBSD Þ ìéá ðéï ðñüóöáôç.  Áí ÷ñçóéìïðïéåßôå ôçí Ýêäïóç 4.X,
	    ôüôå èá ðñÝðåé íá åíåñãïðïéÞóåôå ôçí åðéëïãÞ
	    <emphasis>IPFW2</emphasis> êáé íá äéáâÜóåôå ôç óåëßäá âïÞèåéáò
	    &man.ipfw.8; ãéá ðåñéóóüôåñåò ðëçñïöïñßåò ó÷åôéêÜ ìå ôçí åðéëïãÞ
	    IPFW2.  ÐñïóÝîôå éäéáßôåñá ôï
	    ôìÞìá <emphasis>USING IPFW2 IN FreeBSD-STABLE</emphasis>.</para>
	  </note>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><literal>options IPFIREWALL_VERBOSE</literal></term>

        <listitem>
          <para>ÓôÝëíåé ôá ìçíýìáôá ãéá ôá êáôÜëëçëá ðáêÝôá óôï log ôïõ
            óõóôÞìáôïò.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><literal>options
            IPFIREWALL_VERBOSE_LIMIT=<replaceable>500</replaceable></literal></term>

        <listitem>
          <para>ÂÜæåé êÜðïéï üñéï óôéò öïñÝò ðïõ êÜðïéá åããñáöÞ èá
            êáôáãñÜöåôáé.  ¸ôóé ìðïñåßôå íá êáôáãñÜöåôå ôá ìçíýìáôá áðü ôï
	    ôåß÷ïò ðñïóôáóßáò ÷ùñßò ôïí êßíäõíï íá ãåìßóïõí ôá áñ÷åßá
	    êáôáãñáöÞò ôïõ óõóôÞìáôüò óáò áí äå÷ôåßôå êÜðïéá åðßèåóç.
	    Ôï üñéï <replaceable>500</replaceable> ìçíõìÜôùí åßíáé ìéá áñêåôÜ
	    ëïãéêÞ ôéìÞ, áëëÜ ìðïñåßôå íá ðñïóáñìüóåôå áõôÞ ôçí ôéìÞ áíÜëïãá
	    ìå ôéò áðáéôÞóåéò ôïõ äéêïý óáò äéêôýïõ.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><literal>options IPDIVERT</literal></term>

        <listitem>
          <para>Åíåñãïðïéåß ôá <emphasis>divert</emphasis> sockets, ðïõ èá
            äïýìå áñãüôåñá ôé êÜíïõí.</para>
        </listitem>
      </varlistentry>
    </variablelist>

    <warning>
      <para>Ìüëéò ôåëåéþóåôå ìå ôéò ñõèìßóåéò êáé ôçí ìåôáãëþôôéóç ôïõ ðõñÞíá
	óáò <emphasis>ìçí êÜíåôå åðáíåêêßíçóç!</emphasis>  Áí êÜíåôå
	åðáíåêêßíçóç óå áõôü ôï óçìåßï ìðïñåß íá êëåéäùèåßôå áðÝîù áðü ôï
	óýóôçìÜ óáò.  ÐñÝðåé íá ðåñéìÝíåôå ìÝ÷ñé íá åãêáôáóôáèïýí ïé êáíüíåò
	ôïõ ôåß÷ïõò ðñïóôáóßáò êáé íá åíçìåñùèïýí üëá ôá ó÷åôéêÜ áñ÷åßá
	ñõèìßóåùí.</para>
    </warning>
  </sect1>

  <sect1 id="rcconf">
    <title>ÁëëáãÝò óôï <filename>/etc/rc.conf</filename> ãéá íá öïñôþíåôáé
      ôï ôåß÷ïò ðñïóôáóßáò</title>

    <para>Ãéá íá åíåñãïðïéåßôáé ôï ôåß÷ïò ðñïóôáóßáò êáôÜ ôçí åêêßíçóç ôïõ
      óõóôÞìáôïò êáé ãéá íá ïñßóåôå ôï áñ÷åßï ìå ôïõò êáíüíåò ôïõ ôåß÷ïõò
      ðñïóôáóßáò, ðñÝðåé íá åíçìåñþóåôå ôï
      áñ÷åßï <filename>/etc/rc.conf</filename>.  ÁðëÜ ðñïóèÝóôå ôéò ðáñáêÜôù
      ãñáììÝò:</para>

    <programlisting>firewall_enable="YES"
firewall_script="/etc/firewall/fwrules"</programlisting>

    <para>Ãéá ðåñéóóüôåñåò ðëçñïöïñßåò ó÷åôéêÜ ìå ôç óçìáóßáò êáèåìéÜò áðü
      áõôÝò ôéò ãñáììÝò, ñßîôå ìéá ìáôéÜ óôï
      <filename>/etc/defaults/rc.conf</filename> êáé äéáâÜóôå ôçí man óåëßäá
      &man.rc.conf.5;</para>
  </sect1>

  <sect1>
    <title>ÅíåñãïðïéÞóôå ôçí ÅíóùìáôùìÝíç ÌåôÜöñáóç Äéåõèýíóåùí ôïõ PPP</title>

    <para>Ãéá íá åðéôñÝøåôå óå Üëëá ìç÷áíÞìáôá ôïõ äéêôýïõ óáò íá óõíäÝïíôáé
      ìå ôïí Ýîù êüóìï ìÝóù ôïõ FreeBSD, ÷ñçóéìïðïéþíôáò ôï
      ùò <quote>ðýëç</quote>, èá ðñÝðåé íá åíåñãïðïéÞóåôå ôçí åíóùìáôùìÝíç
      ìåôÜöñáóç äéåõèýíóåùí ôïõ PPP (NAT).  Ãéá íá ãßíåé áõôü, ðñïóèÝóôå óôï
      áñ÷åßï <filename>/etc/rc.conf</filename> ôéò ðáñáêÜôù ãñáììÝò:</para>

    <programlisting>ppp_enable="YES"
ppp_mode="auto"
ppp_nat="YES"
ppp_profile="<replaceable>ðñïößë_ôçò_óýíäåóçò</replaceable>"</programlisting>

    <para>Óôç èÝóç ôïõ <literal>ðñïößë_ôçò_óýíäåóçò</literal> ðñÝðåé íá âÜëåôå
      ôï üíïìá ôçò óýíäåóÞò óáò, üðùò ôï Ý÷åôå áðïèçêåýóåé óôï
      áñ÷åßï <filename>/etc/ppp/ppp.conf</filename>.</para>
  </sect1>

  <sect1 id="rules">
    <title>Ïé êáíüíåò ôïõ firewall</title>

    <para>Ôï ìüíï ðïõ áðïìÝíåé ôþñá åßíáé íá ïñßóïõìå ôïõò êáíüíåò ôïõ
      firewall.  Ïé êáíüíåò ôïõò ïðïßïõò ðåñéãñÜöïõìå åäþ åßíáé áñêåôÜ êáëïß
      ãéá ôïõò ðåñéóóüôåñïõò ÷ñÞóôåò ìå dialup óýíäåóç, áëëÜ ïýôå õðï÷ñåùôéêïß
      åßíáé, ïýôå åßíáé äõíáôüí íá ôáéñéÜæïõí ìå ôéò áíÜãêåò üëùí ôùí ÷ñçóôþí
      dialup.  Ìðïñïýí, üìùò, íá ÷ñçóéìåýóïõí ùò Ýíá êáëü ðáñÜäåéãìá ñõèìßóåùí
      ôïõ IPFW êáé åßíáé ó÷åôéêÜ åýêïëï íá ôïõò ðñïóáñìüóåôå óôéò äéêÝò óáò
      áíÜãêåò.</para>

    <para>Áò áñ÷ßóïõìå üìùò ìå ôéò âáóéêÝò áñ÷Ýò åíüò êëåéóôïý ôåß÷ïõò
      ðñïóôáóßáò.  ¸íá êëåéóôü ôåß÷ïò ðñïóôáóßáò áðáãïñåýåé êáô' áñ÷Þí êÜèå
      óýíäåóç.  Ï äéá÷åéñéóôÞò ìðïñåß ýóôåñá íá ðñïóèÝóåé êáíüíåò ãéá íá
      åðéôñÝøåé ìüíï óõãêåêñéìÝíåò óõíäÝóåéò íá ðåñíÜíå áðü ôï ôåß÷ïò
      ðñïóôáóßáò.  Ç ðéï óõíçèéóìÝíç óåéñÜ ôùí êáíüíùí óå Ýíá êëåéóôü ôåß÷ïò
      åßíáé: ðñþôá ïé êáíüíåò ðïõ åðéôñÝðïõí ìåñéêÝò óõíäÝóåéò, êáé ôÝëïò ïé
      êáíüíåò ðïõ áðáãïñåýïõí ïðïéáäÞðïôå Üëëç óýíäåóç.  Ç ëïãéêÞ ðßóù áðü
      áõôü åßíáé üôé ðñþôá âÜæåôå ôïõò êáíüíåò ðïõ åðéôñÝðïõí ðñÜãìáôá íá
      ðåñÜóïõí êáé ýóôåñá üëá ôá Üëëá áðáãïñåýïíôáé áõôüìáôá.</para>

    <para>ÖôéÜîôå, ëïéðüí, Ýíá êáôÜëïãï óôïí ïðïßï èá áðïèçêåýïíôáé ïé êáíüíåò
      ôïõ ôåß÷ïõò ðñïóôáóßáò.  Óå áõôü ôï Üñèñï ÷ñçóéìïðïéïýìå ùò ðáñÜäåéãìá
      ôïí êáôÜëïãï <filename
      class="directory">/etc/firewall</filename>.  ÁëëÜîôå êáôÜëïãï ìÝóá óå
      áõôüí êáé äçìéïõñãÞóôå ôï áñ÷åßï <filename>fwrules</filename> ðïõ ôï
      üíïìÜ ôïõ åß÷áìå ãñÜøåé óôï <filename>rc.conf</filename>.  Óçìåéþóôå ðùò
      ìðïñåßôå íá áëëÜîåôå ôï üíïìá ôïõ áñ÷åßïõ áõôïý óå üôé èÝëåôå.  Áõôüò ï
      ïäçãüò äßíåé áõôü ôï üíïìá óáí ðáñÜäåéãìá êáé ìüíï.</para>

    <para>Áò äïýìå ôþñá Ýíá ðáñÜäåéãìá ôåß÷ïõò ðñïóôáóßáò ìå áñêåôÜ
      åðåîçãçìáôéêÜ ó÷üëéá.</para>

    <programlisting># Define the firewall command (as in /etc/rc.firewall) for easy
# reference.  Helps to make it easier to read.
fwcmd="/sbin/ipfw"

# Define our outside interface.  With userland-ppp this
# defaults to tun0.
oif="tun0"

# Define our inside interface.  This is usually your network
# card.  Be sure to change this to match your own network 
# interface.
iif="fxp0"

# Force a flushing of the current rules before we reload.
$fwcmd -f flush

# Divert all packets through the tunnel interface.
$fwcmd add divert natd all from any to any via tun0

# Check the state of all packets.
$fwcmd add check-state

# Stop spoofing on the outside interface.
$fwcmd add deny ip from any to any in via $oif not verrevpath

# Allow all connections that we initiate, and keep their state,
# but deny established connections that don't have a dynamic rule.
$fwcmd add allow ip from me to any out via $oif keep-state
$fwcmd add deny tcp from any to any established in via $oif

# Allow all connections within our network.
$fwcmd add allow ip from any to any via $iif

# Allow all local traffic.
$fwcmd add allow all from any to any via lo0
$fwcmd add deny all from any to 127.0.0.0/8
$fwcmd add deny ip from 127.0.0.0/8 to any

# Allow internet users to connect to the port 22 and 80.
# This example specifically allows connections to the sshd and a
# webserver.
$fwcmd add allow tcp from any to me dst-port 22,80 in via $oif setup keep-state

# Allow ICMP packets: remove type 8 if you don't want your host
# to be pingable.
$fwcmd add allow icmp from any to any via $oif icmptypes 0,3,8,11,12

# Deny and log all the rest.
$fwcmd add deny log ip from any to any</programlisting>

    <para>Ôþñá Ý÷åôå Ýíá ïëïêëçñùìÝíï ôåß÷ïò ðñïóôáóßáò, ôï ïðïßï óõíäÝóåéò óôéò
      èýñåò 22 êáé 80 êáé êáôáãñÜöåé üëåò ôéò Üëëåò óõíäÝóåéò óôï áñ÷åßï êáôáãñáöÞò ôïõ
      óõóôÞìáôïò.  ÐëÝïí åßóôå Ýôïéìïé ãéá åðáíåêêßíçóç.  Ôï ôåß÷ïò ðñïóôáóßáò èá
      åíåñãïðïéçèåß áõôüìáôá êáé èá öïñôþóåé ôïõò êáíüíåò ðïõ ðñïóèÝóáôå.  Áí äå ãßíåé áõôü Þ Ý÷åôå
      ïðïéáäÞðïôå ðñïâëÞìáôá, Þ áí Ý÷åôå êÜðïéåò ðñïôÜóåéò ãéá íá
      äéïñèùèåß áõôü ôï Üñèñï, åðéêïéíùíÞóôå ìáæß ìïõ ìå email.</para>
  </sect1>

  <sect1>
    <title>ÅñùôÞóåéò</title>

    <qandaset>
      <qandaentry>
        <question>
          <para>ÂëÝðù ìçíýìáôá üðùò <errorname>limit 500 reached on entry
            2800</errorname> êáé ìåôÜ áðü áõôü ôï óýóôçìÜ ìïõ óôáìáôÜåé íá
            êáôáãñÜöåé ôá ðáêÝôá ðïõ åìðïäßæïíôáé áðü ôï ôåß÷ïò ðñïóôáóßáò.
            Äïõëåýåé áêüìá ôï firewall ìïõ;</para>
        </question>

        <answer>
          <para>Áõôü áðëÜ óçìáßíåé ðùò Ý÷åé ÷ñçóéìïðïéçèåß ôï ìÝãéóôï üñéï
            êáôáãñáöÞò (logging) ãéá áõôü ôïí êáíüíá.  Ï êáíüíáò ï ßäéïò
            åîáêïëïõèåß íá äïõëåýåé, áëëÜ äåí èá óôÝëíåé ðéá ìçíýìáôá óôï áñ÷åßï êáôáãñáöÞò
            ôïõ óõóôÞìáôïò ìÝ÷ñé íá ìçäåíßóåôå ðÜëé ôïõò ìåôñçôÝò.  Ìðïñåßôå
            íá ìçäåíßóåôå ôïõò ìåôñçôÝò ìå ôçí åíôïëÞ</para>

	  <screen>&prompt.root; <userinput>ipfw resetlog</userinput></screen>

	  <para>ÅíáëëáêôéêÜ, ìðïñåßôå íá áõîÞóåôå ôï üñéï
            êáôáãñáöÞò óôéò ñõèìßóåéò ôïõ ðõñÞíá óáò ìå ôçí åðéëïãÞ
            <option>IPFIREWALL_VERBOSE_LIMIT</option> üðùò ðåñéãñÜøáìå
            ðáñáðÜíù.  Ìðïñåßôå íá áëëÜîåôå áõôü ôï üñéï (÷ùñßò íá
            ìåôáãëùôôßóåôå ðÜëé ôïí ðõñÞíá óáò êáé íá êÜíåôå reboot)
            ÷ñçóéìïðïéþíôáò ôçí &man.sysctl.8; ôéìÞ
            net.inet.ip.fw.verbose_limit.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question>
          <para>ÊÜðïéï ëÜèïò ðñÝðåé íá Ýãéíå.  Áêïëïýèçóá ôéò åíôïëÝò êáôÜ
          ãñÜììá êáé ôþñá êëåéäþèçêá áðÝîù.</para>
        </question>

        <answer>
          <para>Áõôüò ï ïäçãüò õðïèÝôåé üôé ÷ñçóéìïðïéåßôå ôï
            <emphasis>userland-ppp</emphasis>, ãé áõôü êé ïé êáíüíåò ðïõ
            äßíïíôáé ÷ñçóéìïðïéïýí ôï <devicename>tun0</devicename> interface,
            ðïõ áíôéóôïé÷åß óôçí ðñþôç óýíäåóç ðïõ öôéÜ÷íåôáé ìå ôï
            &man.ppp.8; (áëëéþò ãíùóôü êáé ùò <emphasis>user-ppp</emphasis>).
            Ç åðüìåíç óýíäåóç èá ÷ñçóéìïðïéïýóå ôï
            <devicename>tun1</devicename>, ìåôÜ ôï
            <devicename>tun2</devicename> êáé ðÜåé ëÝãïíôáò.</para>

          <para>Èá ðñÝðåé åðßóçò íá èõìÜóôå üôé ôï &man.pppd.8; ÷ñçóéìïðïéåß
            ôï interface <devicename>ppp0</devicename>, ïðüôå áí îåêéíÞóåôå ôç
            óýíäåóÞ óáò ìå ôï &man.pppd.8; èá ðñÝðåé íá áíôéêáôáóôÞóåôå ôï
            <devicename>tun0</devicename> ìå <devicename>ppp0</devicename>.
            ÐáñáêÜôù èá äåßîïõìå Ýíá åýêïëï ôñüðï íá áëëÜîåôå ôïõò êáíüíåò ôïõ
            firewall êáôÜëëçëá.  Ïé áñ÷éêïß êáíüíåò óþæïíôáé óå Ýíá áñ÷åßï ìå
            üíïìá <filename>fwrules_tun0</filename>.</para>

          <screen>          &prompt.user; <userinput>cd /etc/firewall</userinput>
            /etc/firewall&prompt.user; <userinput>su</userinput>
            <prompt>Password:</prompt>
            /etc/firewall&prompt.root; <userinput>mv fwrules fwrules_tun0</userinput>
            /etc/firewall&prompt.root; <userinput>cat fwrules_tun0 | sed s/tun0/ppp0/g > fwrules</userinput>
          </screen>

          <para>Ãéá íá êáôáëÜâåôå áí ÷ñçóéìïðïéåßôå ôï &man.ppp.8; Þ ôï
            &man.pppd.8; ìðïñåßôå íá åîåôÜóåôå ôçí Ýîïäï ôçò &man.ifconfig.8;
            áöïý åíåñãïðïéçèåß ç óýíäåóÞ óáò.  Ð.÷., ãéá ìéá óýíäåóç ðïõ
            åíåñãïðïéÞèçêå áðü ôï &man.pppd.8; èá äåßôå êÜôé óáí áõôü
            (äåß÷íïíôáé ìüíï ïé ó÷åôéêÝò ãñáììÝò):</para>

          <screen>          &prompt.user; <userinput>ifconfig</userinput>
            <emphasis>(skipped...)</emphasis>
            ppp0: flags=<replaceable>8051&lt;UP,POINTOPOINT,RUNNING,MULTICAST&gt; mtu 1524</replaceable>
                    inet <replaceable>xxx.xxx.xxx.xxx</replaceable> --&gt; <replaceable>xxx.xxx.xxx.xxx</replaceable> netmask <replaceable>0xff000000</replaceable>
            <emphasis>(skipped...)</emphasis>
            </screen>

          <para>Áðü ôçí Üëëç, ãéá ìéá óýíäåóç ðïõ åíåñãïðïéÞèçêå ìå ôï
            &man.ppp.8; (<emphasis>user-ppp</emphasis>) èÜ ðñåðå íá äåßôå êÜôé
            ðáñüìïéï ìå ôï ðáñáêÜôù:</para>

          <screen>          &prompt.user; <userinput>ifconfig</userinput>
            <emphasis>(skipped...)</emphasis>
            ppp0: flags=<replaceable>8010&lt;POINTOPOINT,MULTICAST&gt; mtu 1500</replaceable>
            <emphasis>(skipped...)</emphasis>
            tun0: flags=<replaceable>8051&lt;UP,POINTOPOINT,RUNNING,MULTICAST&gt; mtu 1524</replaceable>
                    <emphasis>(IPv6 stuff skipped...)</emphasis>
                    inet <replaceable>xxx.xxx.xxx.xxx</replaceable> --&gt; <replaceable>xxx.xxx.xxx.xxx</replaceable> netmask <replaceable>0xffffff00</replaceable>
                    Opened by PID <replaceable>xxxxx</replaceable>
            <emphasis>(skipped...)</emphasis></screen>
        </answer>
      </qandaentry>
    </qandaset>
  </sect1>
</article>

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