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<article lang="ko">

<!-- Header -->

 <artheader>

  <!-- title of HOWTO, include the word HOWTO -->

  <title>Masquerading Made Simple HOWTO</title>

  <author lang="en">
     <firstname>John</firstname>
     <surname>Tapsell</surname>
     <affiliation>
        <address>
           <email>tapselj0 (at) cs.man.ac.uk</email>
        </address>
     </affiliation>
  </author>

  <author lang="en">
     <firstname>Thomas</firstname>
     <surname>Spellman</surname>
     <affiliation>
        <address>
           <email>thomas (at) resonance.org</email>
        </address>
     </affiliation>
  </author>

  <author lang="en">
     <firstname>Matthias</firstname>
     <surname>Grimm</surname>
     <affiliation>
        <address>
           <email>DeadBull (at) gmx.net</email>
        </address>
     </affiliation>
  </author>

  <othercredit role="translator">
     <firstname>Á¤¹Î</firstname>
     <surname>¼­</surname>
     <affiliation>
  	    <address>
	       <email>jms (at) kldp.org</email>
	    </address>
     </affiliation>
  </othercredit>

   <revhistory>
      <revision>
	     <revnumber>¹ø¿ª v0.95</revnumber>
	     <date>2001-09-28</date>
		 <authorinitials>jms</authorinitials>
	  </revision>
      <revision>
	     <revnumber>¹ø¿ª v0.9</revnumber>
	     <date>2001-09-21</date>
		 <authorinitials>jms</authorinitials>
	  </revision>
      <revision>
         <revnumber>0.05</revnumber>
         <date>2001-09-07</date>
         <authorinitials>jpt</authorinitials>
      </revision>

      <!-- Additional (*earlier*) revision histories go here -->
   </revhistory>

  <abstract>
    <indexterm>
      <primary>Abstract</primary>
    </indexterm>
     <para>
      ¸ðµç ÇÊÀÚµéÀº irc.opensource.net ¼­¹öÀÇ #debian Ã¤³Î¿¡ ÀÖ´Ù.
     </para><para>
      John Tapsell(JohnFlux)°¡ ÀÌ ¹®¼­ÀÇ °ø½Ä ¸ÞÀÎÅ×ÀÌ³ÊÀÌ´Ù.
     </para><para>
      ÀÇ¹®Á¡, ¿­Á¤, ÀÇ°ß, ³¯Â¥ µî¿¡ °üÇÑ ¾î¶² °ÍÀÌµç, John Tapsell¿¡°Ô ÀÌ¸ÞÀÏÀ»
	  º¸³»±â ¹Ù¶õ´Ù.
     </para><para>
      David RanchÀÇ ¹®¼­¸¦ »·»·½º·´°Ô µµ¿ëÇÑ Á¡À» ¹àÈù´Ù -
	  <email>dranch(at)trinnet.net</email>.
     </para><para>
      ÀÌ ¹®¼­´Â IP-Masquerading HOWTO ¹®¼­¿¡ ´ëÇÑ ´ëÃ¼°¡ ¾Æ´Ï´Ù. º¸ÃæÇÏ´Â
	  ¹®¼­ÀÌ°í, µÎ ¹®¼­´Â ÇÔ²² º¼ °ÍÀ» ±ÇÇÑ´Ù.  ÀÌ ¹®¼­´Â ±× HOWTO ¹®¼­¿¡¼­
	  °Å·ÐµÈ °ÍÀ» ´Ù½Ã ±â¼úÇÏÁö ¾Ê°í, ±× ¹®¼­¸¦ ¼³¸íÇÏÁöµµ ¾Ê´Â´Ù.  ´õ
	  ÀÚ¼¼ÇÑ ¼³¸í¼­·Î´Â <ulink
	  url="http://ipmasq.cjb.net">http://ipmasq.cjb.net</ulink>°ú the
	  sandard Masq-HOWTO¸¦ º¼ °ÍÀ» ¹Ù¶õ´Ù.
     </para><para>
	  ÁÖ¾îÁø ¸®´ª½º È£½ºÆ®¿¡ IP Masquerade¸¦ ¾î¶»°Ô »ç¿ëÇÏ´ÂÁö¿¡ ´ëÇØ
	  ±â¼úÇÑ´Ù. IP Masq´Â NAT(Netwrk Address Translation)ÀÇ ÇÑ
	  ÇüÅÂ·Î½á,µî·ÏµÈ ÀÎÅÍ³Ý IP¸¦ ¾ø´Â ³»ºÎ ³×Æ®¿öÅ©¿¡ ¿¬°áµÈ ÄÄÇ»ÅÍ·Î
	  ÇÏ¿©±Ý, ´Ü ÇÏ³ªÀÇ ÀÎÅÍ³Ý IPÁÖ¼Ò¸¦ °¡Áø ¸®´ª½º ¹Ú½º¸¦ ÀÌ¿ëÇÏ¿© ÀÎÅÍ³ÝÀ»
	  »ç¿ëÇÒ ¼ö ÀÖµµ·Ï ÇÑ´Ù.
     </para>
     <para>
      ÀÌ ¹®¼­´Â GNU Free Documentation License¸¦ µû¸¥´Ù.
     </para><para>
      <ulink url="http://www.gnu.org/copyleft/fdl.html">
      http://www.gnu.org/copyleft/fdl.html
      </ulink>
     </para>
  </abstract>

 </artheader>

<!-- Section1: intro -->

 <sect1 id="intro">
   <title>¼Ò°³</title>

   <indexterm>
    <primary>¼Ò°³</primary>
   </indexterm>

  <para>
  ÀÌ ¹®¼­´Â ÀÏºÎ·¯ Âª°í ÀÌÇØÇÏ±â ½±°Ô ±¸¼ºµÇ¾ú´Ù.
  </para><para>
  ´ÙÀ½°ú °°Àº ¿ÜºÎ¿Í ¿¬°á½ÃÅ°°í ½ÍÀº ³×Æ®¿öÅ©°¡ ÀÖ´Ù°í ÇÏÀÚ.
  </para><para>
  <literallayout>
   _____________
  /                     \        ¿ÜºÎ IP            _________      ³»ºÎ IP
 |   Internet         |	    123.12.23.43       |  linux     |  192.168.0.1
 |   google.com  | <---[¿ÜºÎ ·£Ä«µå]-| machine |--[³»ºÎ ·£Ä«µå]
  \_____________/                              ---------            |
                                                                                   |
                                      _____________              ______|_______
                                     | 192.168.0.2  |            /                      \
                                     |    ³»ºÎ        |-------|    192.168.0.0     |
                                     |    ÄÄÇ»ÅÍ     |            |      ÀÎÆ®¶ó³Ý      |
                                      -------------             \______________/ 

  </literallayout>
  </para>
 </sect1>



<!-- Section1: summary  -->

 <sect1 id="summary">
  <title>¿ä¾à : (ÇÊÀÚ´Â ¿ä¾àÀ» ¸ÕÀú ÇÏ´Â °ÍÀ» ¼±È£ÇÑ´Ù)</title>

  <para>
   ¿ÜºÎ ·£Ä«µå´Â eth0, ¿ÜºÎ IP´Â 123.12.23.43, ±×¸®°í ³»ºÎ ·£Ä«µå´Â eth1¶ó°í
   °¡Á¤ÇÑ´Ù¸é:
  </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>modprobe ipt_MASQUERADE</command> # ¸¸¾à ½ÇÆÐÇÏ´õ¶óµµ ´ÙÀ½À» °è¼ÓÇÏ½Ã¿À.
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -F; iptables -t nat -F; iptables -t mangle -F</command>
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to 123.12.23.43</command>
<prompt moreinfo="none">$&gt;</prompt> <command>echo 1 > /proc/sys/net/ipv4/ip_forward</command></screen>
   <para>
   Dial-up ¿¬°áÀÇ °æ¿ì:
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>modprobe ipt_MASQUERADE</command> # ¸¸¾à ½ÇÆÐÇÏ´õ¶óµµ ´ÙÀ½À» °è¼ÓÇÏ½Ã¿À. 
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -F; iptables -t nat -F; iptables -t mangle -F</command>
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -t nat -A POSTROUTING -o ppp0 -j MASQUERADE</command>
<prompt moreinfo="none">$&gt;</prompt> <command>echo 1 > /proc/sys/net/ipv4/ip_forward</command></screen>
   <para>
   ±×¸®°í º¸¾ÈÀ» À§ÇØ:
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT</command>
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A INPUT -m state --state NEW -i ! eth0 -j ACCEPT</command>
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -P INPUT DROP</command>  # À§ÀÇ µÎ ÁÙÀÌ ¼º°øÇßÀ» °æ¿ì¿¡¸¸
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A FORWARD -i eth0 -o eth0 -j REJECT</command></screen>
   <para>
   Dial-up ¿¬°áÀÇ °æ¿ì (eth0À» ³»ºÎ·£Ä«µå·Î ÀÌ¿ë½Ã):
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT</command>
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A INPUT -m state --state NEW -i ! ppp0 -j ACCEPT</command>
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -P INPUT DROP</command>  # À§ÀÇ µÎ ÁÙÀÌ ¼º°øÇßÀ» °æ¿ì¿¡¸¸
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A FORWARD -i ppp0 -o ppp0 -j REJECT</command></screen>
   <para>
   ³¡ÀÌ´Ù! "<command>iptables -t nat -L</command>"·Î ±ÔÄ¢À» º¼ ¼ö ÀÖ´Ù.
   </para>
  </sect1>
  
<!-- Section1: indepth -->

  <sect1 id="indepth">
   <title>ÀÚ¼¼ÇÑ ¼³¸í</title>
   <para>
	2.4.x ´ëÀÇ Ä¿³Î ÄÄÆÄÀÏÇÏ´Â °æ¿ì:
   </para>
   <para>
    ´ÙÀ½ÀÇ Ä¿³Î Áö¿øÀÌ ÇÊ¿äÇÏ´Ù.
   </para>
   <itemizedlist>
    <listitem>
     <para>
	  Networking Options ¶õ¿¡¼­ 
     </para>
     <itemizedlist>
      <listitem>
       <para>
        Network packet filtering  (CONFIG_NETFILTER)
       </para>
      </listitem>
     </itemizedlist>
    </listitem>
    <listitem>
     <para>
      Networking Options->Netfilter Configuration ¶õ¿¡¼­
     </para>
     <itemizedlist>
      <listitem>
       <para>
        Connection tracking (CONFIG_IP_NF_CONNTRACK)
       </para>
      </listitem>
      <listitem>
       <para>
        FTP Protocol support (CONFIG_IP_NF_FTP)
       </para>
      </listitem>
      <listitem>
       <para>
        IP tables support (CONFIG_IP_NF_IPTABLES)
       </para>
      </listitem>
      <listitem>
       <para>	
        Connection state match support (CONFIG_IP_NF_MATCH_STATE)
       </para>
      </listitem>
      <listitem>
       <para>
        Packet filtering (CONFIG_IP_NF_FILTER)
       </para>
       <itemizedlist>
        <listitem>
         <para>
	  REJECT target support (CONFIG_IP_NF_TARGET_REJECT)
         </para>
	</listitem>
       </itemizedlist>
      </listitem>
      <listitem>
       <para>
        Full NAT (CONFIG_IP_NF_NAT)
       </para>
       <itemizedlist>
        <listitem>
         <para>
          MASQUERADE target support (CONFIG_IP_NF_TARGET_MASQUERADE)
         </para>
	</listitem>
        <listitem>
         <para>
          REDIRECT target support (CONFIG_IP_NF_TARGET_REDIRECT)
         </para>
        </listitem>
       </itemizedlist>
      </listitem>
      <listitem>
       <para>
        Packet mangling (CONFIG_IP_NF_MANGLE)
       </para>
      </listitem>
      <listitem>
       <para>
        LOG target support (CONFIG_IP_NF_TARGET_LOG)
       </para>
      </listitem>
     </itemizedlist>
    </listitem>
   </itemizedlist>
   <para>
   ¸ÕÀú, iptable°ú masq ¸ðµâÀÌ Ä¿³Î¿¡ ÄÄÆÄÀÏ, ¼³Ä¡°¡ µÇÁö ¾Ê¾ÒÁö¸¸ ¸ðµâ·Î¸¸
   Á¸ÀçÇÏ´Â °æ¿ì, ¼³Ä¡ÇÒ ÇÊ¿ä¼ºÀÌ ÀÖ´Ù. ¸¸¾à 'insmod ipt_MASQUERADE"ÇÑ´Ù¸é,
   ip_tables, ip_conntrack ±×¸®°í iptable_natÀ» ·ÎµåÇÑ´Ù.
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>modprobe ipt_MASQERADE</command></screen>
   <para>
	ÀÎÆ®¶ó³ÝÀÌ Å©°Å³ª, µÎ¼¼´ë ÀÌ»óÀÇ ÄÄÇ»ÅÍ¸¦ ÀÎÅÍ³Ý¿¡ ¿¬°áÇÒ·Á°í ÇÏ´õ¶óµµ
	º°·Î Å« Â÷ÀÌ´Â ¾ø´Ù.
   </para><para>
	ÀÚ, ´Ù¸¥ ·êÀ» °¡Áö°í ÀÖÁö ¾Ê´Ù´Â °¡Á¤ÇÏ¿¡, ´ÙÀ½À» ÇÏ¶ó.
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -F; iptables -t nat -F; iptables -t mangle -F</command></screen>
   <para>
	¸¸¾à iptables¸¦ Ã£À» ¼ö ¾ø´Ù´Â ¿¡·¯°¡ ³¯ °æ¿ì, iptables¸¦ Ã£¾Æ ¼³Ä¡ÇÏ¶ó.
	¸¸¾à nat°ú °°Àº Å×ÀÌºíÀÌ ¾ø´Ù¸é, nat Áö¿øÀ» ³Ö°í ´Ù½Ã Ä¿³ÎÀ» ÄÄÆÄÀÏÇÏ¶ó.
	mangleÀÌ¶õ Å×ÀÌºíÀÌ ¾ø´Ù°í ÇÏ¸é, °ÆÁ¤ÇÏÁö ¸¶¶ó, ¸¶½ºÄ¿·¹ÀÌµù¿¡ ÇÊ¿äÇÑ
	°ÍÀÌ ¾Æ´Ï´Ù. ¸¸¾à iptables°¡ Ä¿³Î°ú ¸ÂÁö ¾Ê´Ù°í ÇÏ¸é(incompatible), 2.4
	ÀÌ»óÀÇ Ä¿³ÎÀ» ±¸ÇÏ¿© iptables Áö¿øÀ» ÇÏ¿© ÄÄÆÄÀÏÇÏ¶ó.
   </para><para>
	±×¸®°í, °íÁ¤ ¾ÆÀÌÇÇÀÎ °æ¿ì (¿¹: DHCP°¡ ¾Æ´Ñ ³×Æ®¿öÅ©):
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to 123.12.23.43</command></screen>
   <para>
	À¯µ¿ ¾ÆÀÌÇÇÀÎ °æ¿ì (¿¹: ¸ðµ© - ÀüÈ­Á¢¼ÓÀ» ¸ÕÀú ÇÏ¶ó):
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -t nat -A POSTROUTING -o ppp0 -j MASQUERADE</command></screen>
   <para>
	¸¶Áö¸·À¸·Î Ä¿³Î¿¡ È®´äÀ» ÁÖ±â À§ÇØ, ÆÐÅ¶Æ÷¿öµùÀ» ÇÑ´Ù (¸Å ¸®ºÎÆÃ½Ã
	ÇÑ¹ø¸¸ ½ÇÇàÇÏ¸é µÇÁö¸¸, ¿©·¯¹ø ÇØµµ »ó°ü¾ø´Ù) :
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>echo 1 > /proc/sys/net/ipv4/ip_forward</command></screen>
   <para>
	ÀÌ ¸ðµç °ÍÀÌ ÀÛµ¿µÉ °æ¿ì, ³»ºÎ ³×Æ®¿öÅ©¿¡¼­ÀÇ ¸¶½ºÄ¿·¹ÀÌµù¸¸ Çã¿ëÇÏ±â¸¦ 
	¹Ù¶õ´Ù(´ÙÀ½Àå Âü°í). - ÀÎÅÍ³ÝÀ» ÅëÇÑ Á¢¼ÓÀ» ¿øÄ¡ ¾ÊÀ» °ÍÀÌ±â ¶§¹®ÀÌ´Ù.
   </para>
   <para>
	¸ÕÀú, ¸ðµç ¿¬°áÀ» Çã¶ôÇÑ´Ù. (e.g. FTP ¼­¹ö ¿¬°á)
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT</command></screen>
   <para>
	¿©±â¿¡¼­ ¿¡·¯°¡ ³­´Ù¸é, Ä¿³ÎÀÌ state trackingÀ» Áö¿øÇÏÁö ¾ÊÀ» °¡´É¼ºÀÌ Å©´Ù.
	ÀçÄÄÆÄÀÏÇÒ °ÍÀ» ±ÇÇÑ´Ù. ±×¸®°í, ÀÌÁ¦ ÀÎÆ®¶ó³Ý(·ÎÄÃ, ³»ºÎ
	³×Æ®¿öÅ©)À¸·ÎºÎÅÍÀÇ »õ·Î¿î ¿¬°á¸¸ Çã¶ôÇÑ´Ù. ppp0¸¦ eth0³ª ÀÚ½ÅÀÇ
	<emphasis>¿ÜºÎ</emphasis> µð¹ÙÀÌ½º·Î ´ëÃ¼ÇÏ¶ó. (!´Â '¿Ü¿¡ ¾î¶² °ÍÀÌµç'¶õ
	¶æÀÌ´Ù)
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A INPUT -m state --state NEW -i ! ppp0 -j ACCEPT</command></screen>
   <para>
	ÀÌÁ¦ ´Ù¸¥ ¸ðµç ¿¬°áÀº ¸·´Â´Ù:
   </para>
   <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -P INPUT DROP</command>  # À§ÀÇ µÎ ÁÙÀÌ ¼º°øÇßÀ» °æ¿ì¿¡¸¸</screen>
   <para>
	Ã³À½ µÎ ·ê Áß¿¡ ÇÏ³ª¶óµµ ½ÇÆÐÇÑ´Ù¸é, ÀÌ ¸¶Áö¸· ·êÀº ¸¶½ºÄ¿·¹ÀÌµùÇÏ´Â
	°ÍÀ» ¸·À» °ÍÀÌ´Ù. ÀÌ ·êÀ» µÇµ¹¸®±â À§ÇØ¼±, "<command>iptables -P INPUT ACCEPT</command>"À» ÇÏ¸é µÈ´Ù.
   </para>   
  </sect1>

<!-- Section1: Post-install -->

  <sect1 id="post-install">   
   <title>¼³Ä¡ ÈÄ¸¦ À§ÇÑ ¼³¸í</title>
    <para>
	 ÀÌÁ¦ ¸ðµç °ÍÀÌ ÀÛµ¿µÉ °ÍÀÌ´Ù.  ´ÙÀ½À» ÀØÁö ¸¶¶ó:
    </para>
     <itemizedlist>
      <listitem>
       <para>
		³»ºÎ ³×Æ®¿öÅ©¿¡ ÀÖ´Â ¸ðµç Å¬¶óÀÌ¾ðÆ®ÀÇ °ÔÀÌÆ®¿þÀÌ °ª¿¡ ³»ºÎ IP
		ÁÖ¼Ò¸¦ ¼³Á¤ÇÑ´Ù. 
		(À©µµ¿ì¿¡¼­´Â ¿À¸¥ÂÊ Å¬¸¯ÇÏ¿© ³×Æ®¿öÅ© È¯°æ->µî·ÏÁ¤º¸->°ÔÀÌÆ®¿þÀÌ¿¡
		°¡¼­ °ªÀ» ¸®´ª½º °ÔÀÌÆ®¿þÀÌ ³»ºÎ IP¸¦ ¼³Á¤ÇÑ´Ù)
       </para>
      </listitem>
      <listitem>
       <para>
		ISPÀÇ HTTP ÇÁ¶ô½Ã°¡ ÀÖ´Ù¸é ¼³Á¤ÇÏ°Å³ª, Åõ¸í ÇÁ¶ô½Ã¸¦ »ç¿ëÇÏ°Ô ¸ðµç
		Å¬¶óÀÌ¾ðÆ®µéÀ» ¼³Á¤ÇÏ°í, (°æ°í - Å« ³×Æ®¿öÅ©¿¡¼­´Â Åõ¸í ÇÁ¶ô½Ã°¡
		¾ÆÁÖ ´À¸®´Ù´Â °ÍÀ» ÀÚÁÖ µé¾ú´Ù) È¤Àº »õ ¸®´ª½º °ÔÀÌÆ®¿þÀÌ¿¡ squid¸¦
		½ÇÇàÇÑ´Ù. (ÀÌ°ÍÀº ¿É¼ÇÀÌÁö¸¸, Å« ³×Æ®¿öÅ©¿¡¼­ ¼±È£ÇÑ´Ù)
       </para>
      </listitem>
      <listitem>
       <para>
		ÀÌÁ¦ º¸¾ÈÀ» »ý°¢ÇØ º¸ÀÚ. ¸ÕÀú ÀÏ¹ÝÀûÀ¸·Î Æ÷¿öµùÀ» ²ôÀÚ:
		"<command>iptables -P FORWARD DROP</command>", ±×¸®°í iptables¿Í
		<filename>/etc/hosts.allow</filename>°ú
		<filename>/etc/hosts.deny</filename> »ç¿ë¹ýÀ» ÀÍÈù´Ù. °æ°í -
		¸¶½ºÄ¿·¹ÀÌµùÀÌ ÀÛµ¿µÉ ¶§±îÁö´Â ÀÌ iptalbes ·êÀ» ½ÃµµÇÏÁö ¸¶¶ó.
		¸¶Áö¸· ·êÀ» DENYÇÒ·Á¸é, ¿øÇÏ´Â ¸ðµç ÆÐÅ¶À» ¸í¹éÇÏ°Ô Åë°úÇÏµµ·Ï ÇØ¾ß
		ÇÑ´Ù. (µÇµ¹¸±·Á¸é, "<command>ipatbles -P FORWARD ACCEPT</command>")
       </para>
      </listitem>
      <listitem>
       <para>
		ÀÌÁ¦ ÀÎÅÍ³ÝÀ¸·Î Á¢¼ÓÇÒ ¼ö ÀÖ´Â ¼­ºñ½º¸¦ Çã¶ôÇÑ´Ù.
       </para>
       <para>
		¿¹¸¦ µé¾î, À¥¼­¹ö Á¢¼ÓÀ» À§ÇØ¼± ´ÙÀ½À» ÇÑ´Ù:
       </para>
       <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A INPUT --protocol tcp --dport 80 -j ACCEPT</command>
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A INPUT --protocol tcp --dport 443 -j ACCEPT</command></screen>
       <para>
		ident¼­ºñ½º(¿¹: irc Á¢¼Ó)¸¦ À§ÇØ¼­´Â ´ÙÀ½À» ÇÑ´Ù:
       </para>
       <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -A INPUT --protocol tcp --dport 113 -j ACCEPT</command></screen>
      </listitem>
     </itemizedlist>

    <para>
	 Å×½ºÆ®ÇÒ·Á¸é:
    </para>

     <itemizedlist>
     <listitem>
      <para>
	   À¥ Á¢¼ÓÀÌ °¡´ÉÇÑ Å¬¶óÀÌ¾ðÆ®¿¡¼­ Á¢¼ÓÀ» ½ÃµµÇÑ´Ù. ±¸±Û IP´Â
	   216.239.33.100(¸¹Àº ±¸±Û IP Áß ÇÏ³ª)ÀÌ°í Á¢¼ÓÀÌ °¡´ÉÇØ¾ß ÇÒ°ÍÀÌ´Ù.
	   ¿¹: "<command>ping 216.239.33.100</command>" "<command>lynx 216.239.33.100</command>".
      </para>
     </listitem>
     <listitem>
      <para>
	   µµ¸ÞÀÎ ³×ÀÓÀ¸·ÎÀÇ Á¢¼ÓÀÌ °¡´ÉÇÑÁöµµ ½ÃµµÇÑ´Ù. ¿¹: "<command>ping
	   google.com</command>" "<command>lynx google.com</command>" È¤Àº
	   IE/Netscape·ÎÀÇ Á¢¼Ó
      </para>
     </listitem>
     </itemizedlist>

    <para>
	 eth0´Â ¿ÜºÎ ÀÎÅÍ³Ý Ä«µåÀÌ°í, 123.12.23.43Àº ¿ÜºÎ IPÀÌ´Ù.
    </para>

  </sect1>

<!-- Section1: FAQ -->

  <sect1 id="FAQ">
   <title>FAQ's</title>
   <itemizedlist>
    <listitem>
     <para>
	  ³»°¡ ÀÌ¿ëÇÑ ·êµéÀ» º¼·Á¸é?
     </para><para>
      - ´ÙÀ½À» ½ÃµµÇÑ´Ù.
      <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -L</command>
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -t nat -L</command></screen>
     </para>
    </listitem>
    <listitem>   
     <para>    
	  ¾ÈµÈ´Ù! iptables/NAT/SNAT/MASQ ¸ðµÎ ¾ÈµÈ´Ù.
     </para><para>
	  - ÃÖ½ÅÀÇ Ä¿³ÎÀ» ±¸ÇÏ¿© iptables¿Í NAT ¿É¼Ç Áö¿øÀ¸·Î ÄÄÆÄÀÏÇÏ¶ó.
     </para>
    </listitem>
    <listitem>
     <para>
	  ¾ÈµÈ´Ù! ¸¶½ºÄ¿·¹ÀÌµùÀÌ ÀüÇô ÀÛµ¿À» ¾ÈÇÑ´Ù.
     </para><para>
      - Try <command>echo 1 > /proc/sys/net/ipv4/ip_forward</command>
     </para>
    </listitem>
    <listitem>
     <para>
	  ¾ÈµÈ´Ù! ³×Æ®¿öÅ© ÀÚÃ¼°¡ ¾ÈµÈ´Ù.
     </para><para>
      - ´ÙÀ½À» ½ÃµµÇÑ´Ù. 
      <screen format="linespecific">
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -F</command>
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -t nat -F</command>
<prompt moreinfo="none">$&gt;</prompt> <command>iptables -t mangle -F</command></screen>
     </para><para>
	 ¸ðµç ·êÀÌ ¾ÈµÈ´Ù¸é, ´Ù¸¥ iptables ·êµéÀ» Àç½ÇÇàÇÑ´Ù.
     </para>
     <para>
      - <command>iptables -P FORWARD ACCEPT</command>¸¦ ½ÃµµÇÑ´Ù.
     </para>
    </listitem>
    <listitem>
     <para>
	  ¾ÆÁ÷ ÀÛµ¿À» ¾ÈÇÑ´Ù!
     </para><para>
	  - "<command>dmesg | tail</command>"´Â ¿¡·¯³ª´Â°¡? ¾Æ´Ï¸é "<command>
		cat /var/log/messages | tail</command>"´Â ¾î¶°ÇÑ°¡?
     </para>
    </listitem>
    <listitem>
     <para>
	  ÀÌÇØ°¡ ¾È°£´Ù, ±×³É ÀÛµ¿À» ¾ÈÇÑ´Ù!
     </para><para>
	  - ¸ð¸£°Ú´Ù. ±×·¯³ª ´ÙÀ½ÀÌ °¡´ÉÇØ¾ß ÇÑ´Ù:
     </para><screen format="linespecific">
1) °ÔÀÌÆ®¿þÀÌ¿¡¼­ ¿ÜºÎ·Î ÇÎÀÌ °£´Ù.
2) °ÔÀÌÆ®¿þÀÌ¿¡¼­ ³»ºÎ Å¬¶óÀÌ¾ðÆ®¿¡ ÇÎÀÌ °£´Ù.
3) ³»ºÎ Å¬¶óÀÌ¾ðÆ®¿¡¼­ °ÔÀÌÆ®¿þÀÌ·Î ÇÎÀÌ °£´Ù.</screen>
     <para>
	  ÀÌ°ÍÀº ¸¶½ºÄ¿·¹ÀÌµîÀ» ½ÃµµÇÏ±â <emphasis>Àü¿¡</emphasis> °¡´ÉÇØ¾ß
	  ÇÑ´Ù.
     </para> 
    </listitem>
    <listitem>
     <para>
	  ÀÌ°ÍÀ» ¾îµð´Ù°¡ ´Ù ³Ö´Â°¡?
     </para>
     <para>
	  - <filename>/etc/network/interfaces</filename> ÆÄÀÏÀÌ³ª firewall.rc¿¡
		³Ö´Â´Ù.  interfaces ÆÄÀÏ¿¡ ³Ö´Â´Ù¸é, ¿ÜºÎ ÀÎÅÍÆäÀÌ½ºÀÇ ¾Õ¿¡ ¿Ã¸®°í,
		"<command>iptables -t nat -F</command>"¸¦ ³ªÁß¿¡ ³»¸®´Â °ÍÀ¸·Î
		¼³Á¤ÇÑ´Ù.
     </para>
    </listitem>
    <listitem>
     <para>
	  ¿äÃ»½Ã ppp¸¸ ¾î¶»°Ô °¡´ÉÇÏ°Ô ÇÏ´Â°¡?
      How do I get it to only bring the ppp up on demand?
     </para><para>
	  - ISP °ÔÀÌÆ®¿þÀÌÀÇ IP°¡ 23.43.12.43ÀÌ¶ó°í ÇÒ ¶§, ´ÙÀ½ ÇÑÁÙÀ»
		<filename>/erc/ppp/peers/provider</filename>ÀÇ ³¡¿¡ Ãß°¡ÇÏ¶ó.
     </para><para> 
        <command>:23.43.12.43</command>
     </para><para>
		(ÀÌ°ÍÀº À¯µ¿ IP¸¦ À§ÇÑ °ÍÀÌ´Ù - °íÁ¤ IP´Â
		my.<command>external.ip.number:23.43.12.43</command>¶ó°í µÉ °ÍÀÌ´Ù)
     </para><para>
		±×¸®°í ÆÄÀÏÀÇ ³¡¿¡ ¶óÀÎ ÇÏ³ª¸¦ Ãß°¡ÇÑ´Ù:
     </para><para>
        <command>demand</command>
     </para><para>
		pppd´Â ¿¬°áÀÌ ²÷±æ °æ¿ì, "<command>ifdown ppp0</command>" È¤Àº
		"<command>poff</command>" ¸í·ÉÀÌ ÀÖÀ» ¶§±îÁö ¹é±×¶ó¿îµå¿¡¼­
		Àç´ÙÀÌ¾óÀ» ½ÃµµÇÑ´Ù.  ÀÌ°ÍÀº "<command>nopersist</command>" ¿É¼ÇÀ»
		¼±ÅÃÇÏÁö ¾ÊÀ» °æ¿ìÀÌ°í, ¼±ÅÃÇÑ´Ù¸é ¿¬°áÀÌ ²÷±âÀÚ¸¶ÀÚ, pppd´Â ¸ØÃâ
		°ÍÀÌ´Ù.  10ºÐÀ» º¸·ùÇÑ µÚ ¿¬°áÀ» ²÷°í ½Í´Ù¸é, "<command>idle
		600</command>"¶õ »õ·Î¿î ¶óÀÎÀ» Ãß°¡ÇÏ¸é µÈ´Ù.
     </para><para>
     </para>
    </listitem>
    <listitem>
     <para>
	  ¿¬°áÀÌ °è¼Ó Á×´Â´Ù!
      </para><para>
	  - Ã¹¹øÂ°, ´ÙÀÌ¾ó¸µÀ» ¿ä±¸ÇÏ´Â°¡? ±×³É ¿ø·¡ ±×·¸°Ô µÇµµ·Ï µÇ¾îÀÖ´Â°Ç
		¾Æ´Ñ°¡? /etc/ppp/peers/provider¸¦ Ã¼Å©ÇÏ¶ó, ±×¸®°í ¸¶½ºÄ¿·¹µùÇÏ±â
		Àü¿¡ ´ÙÀÌ¾ó¸µÀÌ µÇ´ÂÁö È®ÀÎÇÏ¶ó.
      </para><para>
	  - µÎ¹øÂ°, ¸¸¾à À§ÀÇ ¹®Á¦°¡ ¾Æ´Ï¶ó¸é, ³ª°°ÀÌ ¾û¶×ÇÏ°Ô µ¹¾Æ°¡°í ÀÖÀ»Áöµµ
		¸ð¸¥´Ù.  Ä¿³Î 2.4.3 ¹öÀüÀ¸·Î µ¹¾Æ°¡¼­ ÀÛµ¿µÇ´ÂÁö È®ÀÎÇØºÁ¶ó. (³ªµµ
		¿Ö ±×·±Áö Àß ¸ð¸¥´Ù)
      </para>      
    </listitem>
    <listitem>
     <para>
	 ³ª ÀÌ·± ¹æ¹ýÀÌ ½È´Ù! ¹Ì¸® ¸¸µé¾îÁø ½ºÅ©¸³Æ®³ª GUI³ª ±×·±°ÍµéÀ» ¿øÇÑ´Ù.
     </para><para>
      - ¿©±â¸¦ Âü°íÇÏ¶ó:  <ulink url="http://shorewall.sourceforge.net/">
        http://shorewall.sourceforge.net/</ulink>
     </para>
    </listitem>
    <listitem>
     <para>
	  ÄÉÀÌºí¸ðµ©Àº °íÁ¤ IPÀÎ°¡ µ¿Àû IPÀÎ°¡?
     </para><para>
	  - ÁÁÀº Áú¹®ÀÌ´Ù. µ¿ÀûÀÌ¶ó°í »ý°¢ÇÏ´Â°Ô ³ªÀ» °ÍÀÌ´Ù.
     </para>
    </listitem>
    <listitem>
     <para>
	  DHCP ³×Æ®¿öÅ©´Â °íÁ¤ IPÀÎ°¡ µ¿Àû IPÀÎ°¡?
     </para><para>
	  - µ¿ÀûÀÌ´Ù.
     </para>
    </listitem>
    <listitem>
     <para>
	  ¼­ºñ½º´Â ¾î¶»°Ô ÇÏ´Â°¡?
     </para><para>
	  - IP Æ÷Æ®µéÀ» Æ÷¿öµùÇÏ°Å³ª ¸®´ÙÀÌ·ºÆ®ÇÏ¶ó - ¶Ç ÇÑ¹ø °Å·ÐÇÏÁö¸¸,
		¹æ¾îº®ÀÌ ÇÊ¿äÇÏ´Ù¸é ¼³Ä¡ÇÏ¶ó.
     </para>
    </listitem>
    <listitem>
     <para>
	  Å¬¶óÀÌ¾ðÆ®¿¡¼­ ¸®´ª½º °ÔÀÌÆ®¿þÀÌÀÇ ¿ÜºÎ IP·Î ÇÎÀº µÇ´Âµ¥ ÀÎÅÍ³ÝÀº
	  ¾ÈµÈ´Ù.
     </para><para>
	  - "<command>rmmod iptable_filter</command>"¸¦ ÇØºÁ¶ó. - ´ÙÀ½ ¹öÀü¿¡¼­
		´õ ÀÚ¼¼È÷ ¾ð±ÞÇÏ°Ú´Ù.
     </para><para>
	  - <emphasis>routed</emphasis>³ª <emphasis>gated</emphasis>¸¦ ÀÛµ¿ÇÏÁö
		¾Ê°í ÀÖ´ÂÁö È®ÀÎÇÏ¶ó. - Ã¼Å©¸¦ À§ÇØ¼­´Â, "<command>ps aux | grep -e
		routed -e gated</command>".
     </para><para>
      - ¿©±â¸¦ Âü°íÇÏ¶ó. <ulink url="http://ipmasq.cjb.net">http://ipmasq.cjb.net</ulink>
     </para>
    </listitem>
    <listitem>
     <para>
	  ¼³Á¤µÈ ¿¬°áµéÀ» ¾î¶»°Ô º¸´Â°¡? ¿¹¸¦ µé¾î, netstat..
     </para><para>
      - cat /proc/net/ip_conntrack À» ½ÃµµÇÏ¶ó.
     </para>
    </listitem>
    <listitem>
     <para>
	  squid Á¤º¸¿Í ¶ó¿ìÆÃ µî¿¡ °üÇØ ´õ ¾Ë°í ½Í´Ù!
     </para><para>
      - Advanced Routing HOWTO¸¦ º¼ °ÍÀ» ±ÇÇÑ´Ù.
        http://www.linuxdoc.org/HOWTO/Adv-Routing-HOWTO.html
     </para>
   </listitem>
    <listitem>
     <para>
	  ÀÌ HOWTO ¹®¼­´Â ¾²·¹±âÀÌ´Ù!  ÀÌ ¹®¼­¸¦ ¾´ »ç¶÷µéÇÑÅ× ¾î¶»°Ô µûÁú ¼ö
	  ÀÖ´Â°¡?
     </para><para>
	  - irc.opensource.netÀÇ #debian ¹æ¿¡ °¡¼­ JohnFlux¸¦ Ã£¾Æ¶ó.
	  - ¹ø¿ª¿¡ °üÇÑ °ÍÀÌ¸é, irc.hanirc.orgÀÇ #debian ¹æ¿¡ °¡¼­ hutbaramÀ»
		Ã£¾Æ¶ó.
     </para>
    </listitem>
    <listitem>
     <para>
	  ÀÌ HOWTO ¹®¼­´Â ¾²·¹±âÀÌ´Ù! ´õ ³ªÀº ¹öÀüÀº ¾îµð¼­ ±¸ÇÏ´Â°¡?
     </para><para>
      - <ulink url="http://ipmasq.cjb.net">http://ipmasq.cjb.net</ulink>
     </para><para>
	  - LDPÀÇ Masq-HOWTO ¹®¼­¸¦ Âü°íÇÏ¶ó.
     </para>
    </listitem>    
   </itemizedlist>

  </sect1>
</article>

