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<TITLE>Linux IP Masquerade HOWTO: IP $B%^%9%+%l!<%I$N%F%9%H(B </TITLE>
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<A HREF="IP-Masquerade-HOWTO-6.html">$B<!$N%Z!<%8(B</A>
<A HREF="IP-Masquerade-HOWTO-4.html">$BA0$N%Z!<%8(B</A>
<A HREF="IP-Masquerade-HOWTO.html#toc5">$BL\<!$X(B</A>
<HR>
<H2><A NAME="Testing"></A> <A NAME="s5">5. IP $B%^%9%+%l!<%I$N%F%9%H(B </A></H2>
<P>$B$5$FFq$7$$:n6H$b$d$C$H=*$o$j!"$$$h$$$h(B IP $B%^%9%+%l!<%I$NK\3JE*$J%F%9%H$r$9$k;~$,Mh$^$7$?!#$^$@$G$"$l$P(B Linux $B%\%C%/%9$r:F5/F0$7$F(B /etc/rc.d/rc.firewall $B$,@5>o$K<B9T$5$l$k$3$H$r3NG'$7$^$7$g$&!#$=$N3NG'$,=*$C$?$i<!$OFbIt(B LAN $B$N@\B3$H!"(BLinux $B%[%9%H$+$i%$%s%?!<%M%C%H$X$N@\B3$N$I$A$i$b@5$7$/F0:n$7$F$$$k$3$H$r3NG'$7$F$/$@$5$$!#(B
<P>
<P>$B%^%9%+%l!<%I$N@_Dj$,A4$F@5$7$/9T$o$l$F$$$k$3$H$r3NG'$9$k$?$a$K!"0J2<$N(B 10 $B%9%F%C%W$N%F%9%H$r9T$C$F$/$@$5$$!#(B
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<P>
<H2><A NAME="ss5.1">5.1 $B%m!<%+%k(B PC $B$N@\B3%F%9%H(B</A>
</H2>
<P>
<P>
<UL>
<LI><P>
</LI>
<LI><B>$B%9%F%C%W(B 1 - $B%m!<%+%k(B PC $B$N@\B3%F%9%H(B</B>
<P>$B%^%9%+%l!<%I$5$l$F$$$k%M%C%H%o!<%/$NFbIt$N%3%s%T%e!<%?$G!"<+J,$N(B
$B%m!<%+%k(B IP $B%"%I%l%9$K(B ping $B$rBG$C$F$/$@$5$$(B
($B$D$^$j(B <EM>ping 192.168.0.10 </EM>)$B!#(B
$B$3$N%F%9%H$O(B TCP/IP $B$,%m!<%+%k$N(B PC $B$G@5$7$/F0:n$7$F$$$k$3$H$r(B
$B3NG'$7$^$9!#(B
$B:G6a$N$[$H$s$I$N%*%Z%l!<%F%#%s%0%7%9%F%`$K$O:G=i$+$i(Bping $B%3%^%s%I$,(B
$B$"$j$^$9!#(B
$B%m!<%+%k$N(B IP $B%"%I%l%9$X$N(B ping $B$,@5>o$KF0:n$7$J$$>l9g!"$3$N(B HOWTO $B$G(B
$BA0=R$N(B
<A HREF="IP-Masquerade-HOWTO-4.html#Configuring-clients">$B%/%i%$%"%s%H$N@_Dj(B</A>
$B$G@bL@$7$?DL$j$K(B
$B%/%i%$%"%s%H(B PC $B>e$G(B TCP/IP $B$,@5$7$/@_Dj$5$l$F$$$k$+$r3N$+$a$F$/$@$5$$!#(B
$B=PNO7k2L$O0J2<$N$h$&$K$J$k$O$:$G$9(B(ping $B$rCf;_$9$k$K$O(B Control-C $B$r(B
$B2!$7$F$/$@$5$$(B)$B!#(B
<P>
<P>
<HR>
<PRE>
masq-client# ping 192.168.0.10
PING 192.168.0.10 (192.168.0.10): 56 data bytes
64 bytes from 192.168.0.10: icmp_seq=0 ttl=255 time=0.8 ms
64 bytes from 192.168.0.10: icmp_seq=1 ttl=255 time=0.4 ms
64 bytes from 192.168.0.10: icmp_seq=2 ttl=255 time=0.4 ms
64 bytes from 192.168.0.10: icmp_seq=3 ttl=255 time=0.5 ms
--- 192.168.0.10 ping statistics ---
4 packets transmitted, 4 packets received, 0% packet loss
round-trip min/avg/max = 0.4/0.5/0.8 ms
</PRE>
<HR>
</LI>
</UL>
<P>
<P>
<H2><A NAME="ss5.2">5.2 Linux $B$NFbIt@\B3$N%F%9%H(B</A>
</H2>
<P>
<UL>
<LI><P>
</LI>
<LI><B>$B%9%F%C%W(B 2 - Linux $B$NFbIt@\B3$N%F%9%H(B</B>
<P>$B%^%9%+%l!<%I%5!<%P$G!"%M%C%H%o!<%/%$%s%?!<%U%'!<%9%+!<%I$N(B
$BFbIt(B IP $B%"%I%l%9$K(B ping $B$rBG$C$F$/$@$5$$(B
($B$D$^$j(B <EM>ping 192.168.0.1</EM>)$B!#(B
$B=PNO7k2L$O0J2<$N$h$&$K$J$k$O$:$G$9(B(ping $B$rCf;_$9$k$K$O(B
Control-C $B$r2!$7$F$/$@$5$$(B)$B!#(B
<P>
<HR>
<PRE>
masq-client# ping 192.168.0.1
PING 192.168.0.1 (192.168.0.1): 56 data bytes
64 bytes from 192.168.0.1: icmp_seq=0 ttl=255 time=0.8 ms
64 bytes from 192.168.0.1: icmp_seq=1 ttl=255 time=0.4 ms
64 bytes from 192.168.0.1: icmp_seq=2 ttl=255 time=0.4 ms
64 bytes from 192.168.0.1: icmp_seq=3 ttl=255 time=0.5 ms
--- 192.168.0.1 ping statistics ---
4 packets transmitted, 4 packets received, 0% packet loss
round-trip min/avg/max = 0.4/0.5/0.8 ms
</PRE>
<HR>
</LI>
</UL>
<P>
<H2><A NAME="ss5.3">5.3 Linux $B$N30It@\B3$N%F%9%H(B</A>
</H2>
<P>
<P>
<UL>
<LI><P>
</LI>
<LI><B>$B%9%F%C%W(B 3 - Linux $B$N30It@\B3$N%F%9%H(B</B>
<P>$B<!$K!"%^%9%+%l!<%I!&%5!<%P$N%$%s%?!<%M%C%H$K@\B3$5$l$?(B
$B%M%C%H%o!<%/%$%s%?!<%U%'!<%9%+!<%I$N30It(B IP$B%"%I%l%9$K(B ping $B$r(B
$BBG$C$F$/$@$5$$!#(B
$B$3$N%"%I%l%9$O(B PPP$B!"%$!<%5%M%C%HEy$G(B ISP $B$K@\B3$5$l$?%"%I%l%9$G$9!#(B
$B$3$N(B IP $B%"%I%l%9$,$o$+$i$J$1$l$P!"%$%s%?!<%M%C%H!&%"%I%l%9$r(B
$BD4$Y$k$?$a$K%^%9%+%l!<%I!&%5!<%P>e$G(BLinux$B%3%^%s%I(B
<EM>"/sbin/ifconfig"</EM> $B$r<B9T$7$F$/$@$5$$!#(B
$B=PNO7k2L$O0J2<$N$h$&$K$J$k$O$:$G$9(B(eth0 $B$N(B IP $B%"%I%l%9$rD4$Y$F$$$k>l9g(B)$B!#(B
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<P>
<HR>
<PRE>
eth0 Link encap:Ethernet HWaddr 00:08:C7:A4:CC:5B
inet addr:12.13.14.15 Bcast:64.220.150.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:6108459 errors:0 dropped:0 overruns:0 frame:0
TX packets:5422798 errors:8 dropped:0 overruns:0 carrier:8
collisions:4675 txqueuelen:100
Interrupt:11 Base address:0xfcf0
</PRE>
<HR>
$B$4Mw$NDL$j!"$3$NNc$K$*$$$F30It(B IP $B%"%I%l%9$O(B "12.13.14.15" $B$G$9!#(B
"ifconfig" $B%3%^%s%I$r<B9T$9$k$3$H$G(B IP $B%"%I%l%9$,$o$+$C$?$N$G!"$3$N(B
$B30It(B IP $B%"%I%l%9$K(B ping $B$rBG$A$^$9!#(B
$B$3$l$O%^%9%+%l!<%I!&%5!<%P$,3N$+$K%M%C%H%o!<%/$K@\B3$7$F$$$k$3$H$r(B
$B3N$+$a$k$3$H$K$J$j$^$9!#(B
$B=PNO7k2L$O0J2<$N$h$&$K$J$k$O$:$G$9(B (ping $B$rCf;_$9$k$K$O(B Control-C $B$r(B
$B2!$7$F$/$@$5$$(B)$B!#(B
<P>
<HR>
<PRE>
masq-server# ping 12.13.14.15
PING 12.13.14.15 (12.13.14.15): 56 data bytes
64 bytes from 12.13.14.15: icmp_seq=0 ttl=255 time=0.8 ms
64 bytes from 12.13.14.15: icmp_seq=1 ttl=255 time=0.4 ms
64 bytes from 12.13.14.15: icmp_seq=2 ttl=255 time=0.4 ms
64 bytes from 12.13.14.15: icmp_seq=3 ttl=255 time=0.5 ms
--- 12.13.14.15 ping statistics ---
4 packets transmitted, 4 packets received, 0% packet loss
round-trip min/avg/max = 0.4/0.5/0.8 ms
</PRE>
<HR>
<P>$B$b$7$3$l$i$N%F%9%H$N$I$A$i$+$,F0:n$7$J$$$J$i!"85$KLa$C$F%M%C%H%o!<%/$N(B
$B%1!<%V%k@\B3$r:F3NG'$7!"(B "dmesg" $B%3%^%s%I$r<B9T$7$?$H$-$K(B
$B%^%9%+%l!<%I!&%5!<%P$N(B2$B$D$N(B NIC $B$,I=<($5$l$k$+3NG'$9$kI,MW$,$"$j$^$9!#(B
$B$3$N=PNO7k2L$NNc$O(B "dmesg" $B%3%^%s%I$N=PNO$N:G8e$N$[$&$,0J2<$N$h$&$K(B
$B$J$k$G$7$g$&(B -
<P>
<HR>
<PRE>
.
.
PPP: version 2.3.7 (demand dialling)
TCP compression code copyright 1989 Regents of the University of California
PPP line discipline registered.
3c59x.c:v0.99H 11/17/98 Donald Becker
http://cesdis.gsfc.nasa.gov/linux/drivers/
vortex.html
eth0: 3Com 3c905 Boomerang 100baseTx at 0xfe80, 00:60:08:a7:4e:0e, IRQ 9
8K word-wide RAM 3:5 Rx:Tx split, autoselect/MII interface.
MII transceiver found at address 24, status 786f.
Enabling bus-master transmits and whole-frame receives.
eth1: 3Com 3c905 Boomerang 100baseTx at 0xfd80, 00:60:97:92:69:f8, IRQ 9
8K word-wide RAM 3:5 Rx:Tx split, autoselect/MII interface.
MII transceiver found at address 24, status 7849.
Enabling bus-master transmits and whole-frame receives.
Partition check:
sda: sda1 sda2 < sda5 sda6 sda7 sda8 >
sdb:
.
.
</PRE>
<HR>
<P>$B$^$?!"(B $B$*;H$$$N(B Linux $B%G%#%9%H%j%S%e!<%7%g%s$G$N(B NIC $B$N@_Dj$,!"$3$N(B HOWTO $B$NA0$N$[$&$G?d>)$7$F$$$kDL$j$K@5$7$/@_Dj$5$l$F$$$k$+3NG'$9$k$3$H$rK:$l$J$$$G$/$@$5$$!#(B
</LI>
</UL>
<P>
<P>
<H2><A NAME="ss5.4">5.4 $B%m!<%+%k(B PC $B$+$i(B Linux $B$X$N@\B3%F%9%H(B</A>
</H2>
<P>
<UL>
<LI><P>
</LI>
<LI><B>$B%9%F%C%W(B 4 - $B%m!<%+%k(B PC $B$+$i(B Linux $B$X$N@\B3%F%9%H(B</B>
<P>$B%^%9%+%l!<%I$5$l$F$$$k%M%C%H%o!<%/FbIt$N%3%s%T%e!<%?$+$i!"%^%9%+%l!<%I$7$F$$$k(B Linux $B%\%C%/%9$NFbIt%M%C%H%o!<%/$N%$!<%5%M%C%H!&%+!<%I$N(B IP $B%"%I%l%9$K(B ping $B$rBG$A$^$9(B($B$D$^$j(B <EM>ping 192.168.0.1</EM>)$B!#$3$l$O!"FbIt%M%C%H%o!<%/5Z$S%k!<%F%#%s%0$,@5$7$$$3$H$r8!>Z$7$^$9!#=PNO7k2L$O0J2<$N$h$&$K$J$k$O$:$G$9(B(ping $B$rCf;_$9$k$K$O(B Control-C $B$r2!$7$F$/$@$5$$(B)$B!#(B
<HR>
<PRE>
masq-client# ping 192.168.0.1
PING 192.168.0.1 (192.168.0.1): 56 data bytes
64 bytes from 192.168.0.1: icmp_seq=0 ttl=255 time=0.8 ms
64 bytes from 192.168.0.1: icmp_seq=1 ttl=255 time=0.4 ms
64 bytes from 192.168.0.1: icmp_seq=2 ttl=255 time=0.4 ms
64 bytes from 192.168.0.1: icmp_seq=3 ttl=255 time=0.5 ms
--- 192.168.0.1 ping statistics ---
4 packets transmitted, 4 packets received, 0% packet loss
round-trip min/avg/max = 0.4/0.5/0.8 ms
</PRE>
<HR>
<P>$B$b$7$&$^$/$$$+$J$$$N$J$i!"%^%9%+%l!<%I!&%5!<%P5Z$S(B
$B%/%i%$%"%s%H!&%3%s%T%e!<%?$N%$!<%5%M%C%H!&%+!<%I$N(B "link" $B%i%s%W$,(B
$BE@Et$7$F$$$k$3$H$r3N$+$a$F$/$@$5$$!#(B
$B0lHLE*$K$O3F%$!<%5%M%C%H!&%+!<%I$N8eIt$K$"$k(B LED $B$H%O%V$d%9%$%C%A$r(B
$B;HMQ$7$F$$$k>l9g$O$=$N(B LED $B$,E@Et$7$^$9!#(B
$B$b$7E@Et$7$F$$$J$$$J$i$P!"%^%9%+%l!<%I$5$l$F$$$k%M%C%H%o!<%/$NFbIt$N(B
$B%3%s%T%e!<%?$,(B
<A HREF="IP-Masquerade-HOWTO-4.html#Configuring-clients">$B%/%i%$%"%s%H$N@_Dj(B</A>
$B$N>O$G@bL@$7$?$h$&$K(B
$B@5$7$/@_Dj$5$l$F$$$k$3$H$r3N$+$a$F$/$@$5$$!#(B
$B%^%9%+%l!<%I$5$l$F$$$k%/%i%$%"%s%H$KLdBj$,L5$1$l$P!"(B
$B%M%C%H%o!<%/!&%1!<%V%k$NG[@~$r:F3NG'$7!"%^%9%+%l!<%I$5$l$F$$$k(B
$B%/%i%$%"%s%H!&%3%s%T%e!<%?$N(B NIC $B$H(B Linux $B%\%C%/%9$NFbIt(B NIC $B$N(B
$BN>J}$N(B LINK $B%i%$%H$,E@Et$7$F$$$k$3$H$r3NG'$7$F$/$@$5$$!#(B
<P>
</LI>
</UL>
<P>
<P>
<H2><A NAME="ss5.5">5.5 $BFbIt%^%9%+%l!<%I$N(B ICMP $BE>Aw$N%F%9%H(B </A>
</H2>
<P>
<UL>
<LI><P>
</LI>
<LI><B>$B%9%F%C%W(B 5 - $BFbIt%^%9%+%l!<%I$N(B ICMP $BE>Aw$N%F%9%H(B</B>
<P>$B%^%9%+%l!<%I$5$l$F$$$k%M%C%H%o!<%/FbIt$N%3%s%T%e!<%?$+$i!"(B
$B>e5-%9%F%C%W(B 3 $B$GF@$i$l$?%^%9%+%l!<%I!&%5!<%P$N30It(B IP $B%"%I%l%9$K(B
ping $B$rBG$C$F$/$@$5$$!#(B
$B$3$N%"%I%l%9$O(B PPP$B!"%$!<%5%M%C%HEy$G(B ISP $B$K@\B3$5$l$?%"%I%l%9$G$9!#(B
$B$3$N(B ping $B$O!"%^%9%+%l!<%I$,F0:n$9$k$3$H$r%F%9%H$7$^$9(B($BFC$K(B ICMP $B$O(B
$B%^%9%+%l!<%I$5$l$F$$$^$9(B)$B!#(B
<P>
<P>$B$b$7$&$^$/$$$+$J$$>l9g!"$^$:%^%9%+%l!<%I$5$l$F$$$k%/%i%$%"%s%H(B PC $B$N(B
$B%G%U%)%k%H!&%2!<%H%&%'%$$,%^%9%+%l!<%I!&%5!<%P$NFbIt(B NIC $B$N(B
IP $B%"%I%l%9$r@5$7$/;X$7$F$$$k$+3N$+$a$F$/$@$5$$!#(B
$B$^$?(B /etc/rc.d/rc.firewall $B$N%9%/%j%W%H$,%(%i!<L5$7$KAv$k$3$H$r(B
$B:F3NG'$7$F$/$@$5$$!#(B
$B%F%9%H$N$?$a(B /etc/rc.d/rc.firewall $B$N%9%/%j%W%H$r:FEYAv$i$;$F$_$F!"(B
$B$=$l$,Av$k$+$I$&$+8+$F$/$@$5$$!#(B
$B$^$?$[$H$s$I$N%+!<%M%k$O%G%U%)%k%H$GM-8z$K$J$C$F$$$^$9$,!"(B
$B%+!<%M%k!&%3%s%U%#%.%e%l!<%7%g%s$NCf$N(B "ICMP Masquerading" $B$H(B
/etc/rc.d/rc.firewall $B%9%/%j%W%H$NCf$N(B "IP Forwarding" $B$r(B
$BM-8z$K$7$F$$$k$3$H$r3N$+$a$F$/$@$5$$!#(B
<P>
<P>$B$=$l$G$b$^$@$&$^$/F0:n$7$J$$$J$i!"(BLinux $B%^%9%+%l!<%I!&%5!<%P>e$G(B
$B<!$N%3%^%s%I$rAv$i$;$F$=$N=PNO7k2L$r8+$F$/$@$5$$(B -
<P>
<UL>
<LI><P>
</LI>
<LI> "<EM>ifconfig</EM>" - $B%$%s%?!<%M%C%H$K@\B3$5$l$F$$$k(B
$B%$%s%?!<%U%'!<%9!J(Bppp0 $B$d(B eth0 $B$J$I!K$,@5$7$/F0:n$7$F$$$F!"(B
$B@5$7$$%$%s%?!<%M%C%H@\B3$N(B IP $B%"%I%l%9$,F@$i$l$F$$$k$3$H$r3NG'$7$^$9!#(B
$B$3$N=PNO7k2L$N0lNc$O>e5-%9%F%C%W(B3$B$NCf$G<($5$l$F$$$^$9!#(B
<P>
</LI>
<LI> "<EM>netstat -rn</EM>" - $B%G%U%)%k%H!&%2!<%H%&%'%$(B
(Gateway $B$NNs$NCf$K$"$k(B IP $B%"%I%l%9$r;}$DNs(B) $B$,@_Dj$5$l$F$$$k$3$H$r(B
$B3NG'$7$F$/$@$5$$!#(B
$B$3$N=PNO7k2L$N0lNc$O0J2<$N$h$&$K$J$j$^$9!#(B
<HR>
<PRE>
masq-server# netstat -rn
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
192.168.0.1 0.0.0.0 255.255.255.255 UH 0 16384 0 eth1
12.13.14.15 0.0.0.0 255.255.255.255 UH 0 16384 0 eth0
12.13.14.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
127.0.0.0 0.0.0.0 255.0.0.0 U 0 16384 0 lo
0.0.0.0 12.13.14.1 0.0.0.0 UG 0 16384 0 eth0
</PRE>
<HR>
0.0.0.0 $B$G;O$^$C$F$$$k:G8e$N9T$KCmL\$7$F$/$@$5$$!#(B
$B$=$N(B Gateway $B%U%#!<%k%I$K(B IP $B%"%I%l%9$,$"$j$^$9$M!#(B
$B$=$N%U%#!<%k%I$NCf$K@_Dj$7$?(B IP $B%"%I%l%9$,8+$($J$1$l$P$J$j$^$;$s!#(B
<P>
</LI>
<LI> "<EM>cat /proc/sys/net/ipv4/ip_forward</EM>" - $B$=$N7k2L$,(B "1" $B$K$J$C$F$$$k$3$H$r3NG'$7$F$/$@$5$$!#$=$&$J$C$F$$$l$P(B Linux $B$N%U%)%o!<%G%#%s%0$OM-8z$H$J$C$F$$$^$9!#(B
<P>
</LI>
<LI>2.2.x $B%f!<%6$J$i(B "<EM>/sbin/ipchains -n -L</EM>" $B$H$$$&(B
$B%3%^%s%I$r!"0?$O(B 2.0.x $B%f!<%6$J$i(B "<EM>/sbin/ipfwadm -F -l</EM>"
$B$H$$$&%3%^%s%I$r<B9T$7$F$_$F$/$@$5$$!#(B
$BFC$K%U%)%o!<%G%#%s%0$N>O$rD4$Y$F!"$"$J$?$,%^%9%+%l!<%I$rM-8z$K(B
$B$7$F$$$k$+3NG'$7$F$/$@$5$$!#(B
$BC1=c$J(B rc.firewall $B%k!<%k%;%C%H$r;H$C$?%f!<%6!<$N>l9g!"(B IPCHAINS $B$N(B
$B=PNO7k2L$N0lNc$O0J2<$N$h$&$K$J$k$G$7$g$&!#(B
<HR>
<PRE>
.
.
Chain forward (policy REJECT):
target prot opt source destination ports
MASQ all ------ 192.168.0.0/24 0.0.0.0/0 n/a
ACCEPT all ----l- 0.0.0.0/0 0.0.0.0/0 n/a
.
.
</PRE>
<HR>
</LI>
</UL>
</LI>
</UL>
<P>
<P>
<H2><A NAME="ss5.6">5.6 $B%^%9%+%l!<%I$5$l$?(B ICMP $B$N30ItE>Aw$N%F%9%H(B</A>
</H2>
<P>
<P>
<UL>
<LI><B>$B%9%F%C%W(B 6 - $B%^%9%+%l!<%I$5$l$?(B ICMP $B$N30ItE>Aw$N%F%9%H(B</B>
<P>$B%^%9%+%l!<%I$5$l$F$$$k%M%C%H%o!<%/FbIt$N%3%s%T%e!<%?$+$i!"(B
$B%$%s%?!<%M%C%H>e$N30It$N8GDj(B TCP/IP $B%"%I%l%9$KBP$7$F(B ping $B$r(B
$BBG$A$^$9(B($B$D$^$j(B <EM>ping 152.19.254.81</EM> $B$3$l$O(B
http://metalab.unc.edu$B!!(B-$B!!(BMetaLabs Linux Archive $B$N(B home $B$G$9(B)$B!#(B
$B$3$l$,F0:n$9$k>l9g!"(BICMP $B%^%9%+%l!<%G%#%s%0$,%$%s%?!<%M%C%H>e$G(B
$BF0:n$7$F$$$k$3$H$r0UL#$7$^$9!#(B
$B$b$7$&$^$/$$$+$J$+$C$?>l9g!":FEY%$%s%?!<%M%C%H@\B3$r%A%'%C%/$7$F$/$@$5$$!#(B
$B$=$l$G$b$^$@F0:n$7$F$/$l$J$$>l9g!"C1=c$J(B rc.firewall $B%k!<%k%;%C%H$r(B
$B;HMQ$7$F$$$k$+!"$^$?(B Linux $B%+!<%M%k$G(B ICMP Masqurading $B$rM-8z$K$7$F(B
$B%3%s%Q%$%k$7$F$$$k$3$H$r3N$+$a$F$/$@$5$$!#(B
$B$^$?%k!<%k%;%C%H$NCf$G(B enable IP MASQ $B$,@5$7$$30It%$%s%?!<%U%'!<%9$r(B
$B;X$7$F$$$k$3$H$r3N$a$F$/$@$5$$!#(B
<P>
</LI>
</UL>
<P>
<P>
<H2><A NAME="ss5.7">5.7 DNS $B$r;H$o$J$$%^%9%+%l!<%I5!G=$N%F%9%H(B</A>
</H2>
<P>
<P>
<UL>
<LI><P>
</LI>
<LI><B>$B%9%F%C%W(B 7 - DNS $B$r;H$o$J$$%^%9%+%l!<%I5!G=$N%F%9%H(B</B>
<P>$B$5$F1s3V$N(B IP $B%"%I%l%9$X$N(B TELNET $B$r9T$C$F$_$F$/$@$5$$(B($B$9$J$o$A(B <EM>telnet 152.2.254.81</EM>) (metalab.unc.edu -$B!!$3$N%5!<%P!<$O$9$4$/K;$7$$$N$G%m%0%$%s%W%m%s%W%H$,8=$l$k$^$G;~4V$,$+$+$k$+$b$7$l$^$;$s(B)$B!#(B $B$7$P$i$/$7$F%m%0%$%s!&%W%m%s%W%H$,8=$l$^$7$?$+!#(B $B8=$l$?$J$i!"(BTCP $B$N%^%9%+%l!<%I$O$&$^$/F0:n$7$F$$$^$9!#$b$78=$l$J$1$l$P!"(B198.182.196.55 (www.linux.org) $B$N$h$&$J(B TELNET $B$,;H$($=$&$JB>$N$$$/$D$+$N%[%9%H$X(B TELNET $B$r$7$F$_$F$/$@$5$$!#(B $B$3$l$,$J$*F/$+$J$$>l9g!":#$N$H$3$m(B simple rc.firewall $B%k!<%k%;%C%H$r;HMQ$7$F$$$k$3$H$r3N$+$a$F$/$@$5$$!#$3$N=PNO7k2L$N0lNc$O0J2<$N$h$&$K$J$k$G$7$g$&(B(TELNET $B$+$iH4$1$k$K$O(B Control-D $B$r2!$7$F$/$@$5$$(B)$B!#(B
<HR>
<PRE>
masq-client# telnet 152.2.254.81
Trying 152.2.254.81...
Connected to 152.2.254.81.
Escape character is '^]'.
SunOS 5.7
******************** Welcome to MetaLab.unc.edu *******************
To login to MetaLab as a user, connect to login.metalab.unc.edu.
This machine allows no public telnet logins.
login: Connection closed by foreign host.
</PRE>
<HR>
</LI>
</UL>
<P>
<P>
<H2><A NAME="ss5.8">5.8 DNS $B$r;H$C$?%^%9%+%l!<%I5!G=$N%F%9%H(B</A>
</H2>
<P>
<UL>
<LI><B>$B%9%F%C%W(B 8 - DNS $B$r;H$C$?(B MASQ $B5!G=$N%F%9%H(B</B>
<P>$B$=$l$G$O!"1s3V$N(B HOSTNAME $B$X$N(B TELNET $B$r;n$_$F$/$@$5$$(B
($BNc$($P!"(B <EM>"telnet metalab.unc.edu"</EM> (152.2.254.81))$B!#(B
$B$3$l$,F0:n$9$k$J$i!"(BDNS $B$b$&$^$/F0:n$7$F$$$k$3$H$r0UL#$7$^$9!#(B
$B$b$7%9%F%C%W(B 6 $B$,F0:n$7$?$N$K$3$l$,F0:n$7$J$+$C$?>l9g!"(B
$B%^%9%+%l!<%I$5$l$F$$$k%/%i%$%"%s%H!&%3%s%T%e!<%?$N(B
DNS $B%5!<%P@_Dj$,(B
<A HREF="IP-Masquerade-HOWTO-4.html#Configuring-clients">$B%/%i%$%"%s%H$N@_Dj(B</A>
$B$N>O$G@bL@$7$?$h$&$K@5$7$/@_Dj$5$l$F$$$k$3$H$r3N$+$a$F$/$@$5$$!#(B
<P>
</LI>
</UL>
<P>
<P>
<H2><A NAME="ss5.9">5.9 DNS $B$r;H$C$?%^%9%+%l!<%I5!G=$NDI2C%F%9%H(B</A>
</H2>
<P>
<UL>
<LI><P>
</LI>
<LI><B>$B%9%F%C%W(B 9 - DNS $B$r;H$C$?%^%9%+%l!<%I5!G=$NDI2C%F%9%H(B</B>
<P>$B:G8e$N%F%9%H$H$7$F!"(B<B>$B%^%9%+%l!<%I$5$l$F$$$k%/%i%$%"%s%H!&%^%7%s(B</B>$B$N(B
1 $B$D$+$i$$$/$D$+$N(B <EM>'$B%$%s%?!<%M%C%H(B'</EM> WWW $B%5%$%H$r%V%i%&%:(B
$B$7$F$_$F$/$@$5$$!#(B
$B$=$7$F!"$=$l$i$K%"%/%;%9$G$-$k$+$I$&$+8+$F$/$@$5$$!#(B
$BNc$($P!"(B
<A HREF="http://metalab.unc.edu/LDP">Linux Documentation Project site</A> $B$X%"%/%;%9$7$F$_$F$/$@$5$$!#(B
$B$b$7$3$l$,$G$-$k$J$i!"$9$Y$F$,$&$^$/F0:n$7$F$$$k(B!$B$H9M$($i$l$^$9!#(B
$B$b$7B>$N%5%$%H$G$OLdBj$,L5$$$N$K!"$$$/$D$+$N%5%$%H$KLdBj$,$"$k>l9g!"(B
$B0J2<$N%9%F%C%W$K$"$k2r7h:v$r8+$F$/$@$5$$!#(B
<P>
<P>$B$b$7!"(B Linux Documentation Project $B$N%[!<%`%Z!<%8$,8+$($?$J$i(B
<B>$B$*$a$G$H$&(B! $B$&$^$/$$$-$^$7$?$M(B! </B>
$B$b$7!"$=$N(B WWW $B%5%$%H$,@5$7$/8+$i$l$k$J$i!"(B PING, TELNET, SSH $B$d!"(B
$B4XO"$9$k(B IP $B%^%9%+%l!<%I!&%b%8%e!<%k$,%m!<%I$5$l$?(B FTP, Real Audio,
IRC DCCs, Quake I/II/III, CuSeeme, VDOLive $B$J$I!"B>$NI8=`E*$J(B
$B%M%C%H%o!<%/@\B3$OA4$F$&$^$/F0:n$9$k$O$:$G$9!#(B
$B$b$7!"(BFTP, IRC, RealAudio, Quake I/II/III $BEy$,F0:n$7$J$$$+!"$"$k$$$O(B
$BF0:n$,IT40A4$J$i$P!"(B "lsmod" $B$r<B9T$7$F!"$=$l$i$KI,MW$J(B
$B%^%9%+%l!<%I!&%b%8%e!<%k$,%m!<%I$5$l$F$$$k$3$H$r3N$+$a$F$/$@$5$$!#(B
$B$^$?!"%G%U%)%k%H$G$OAH$_9~$^$l$J$$%5!<%S%9$KI,MW$J%]!<%H$N%b%8%e!<%k$r(B
$B%m!<%I$7$F$$$k$+$r3NG'$7$F$/$@$5$$!#(B
$B$b$7I,MW$J%b%8%e!<%k$,8+$D$+$i$J$1$l$P!"$"$J$?$N(B
/etc/rc.d/rc.firewall $B%9%/%j%W%H$,$=$l$i$N%b%8%e!<%k$r%m!<%I$7$F$$$k(B
$B$3$H$r3N$+$a$F$/$@$5$$(B
($B$D$^$j!"(BIP $B%^%9%+%l!<%I!&%b%8%e!<%k$rAH$_9~$`$?$a$K(B # $B$NJ8;z$r(B
$B:o=|$7$^$9(B)$B!#(B
<P>
</LI>
</UL>
<P>
<P>
<H2><A NAME="ss5.10">5.10 $B$=$NB>$N5!G=!"@-G=$K4X$9$k;v9`(B</A>
</H2>
<P>
<UL>
<LI><B>$B%9%F%C%W(B 10 - $B$=$NB>$N5!G=!"@-G=$K4X$9$k;v9`(B</B>
<P>$B$b$7!"$"$J$?$N%7%9%F%`$,$3$l$iA4$F$N%F%9%H$K9g3J$7$?$N$K!"(B
WWW $B%V%i%&%8%s%0$d(B FTP $B$^$?$OB>$N%?%$%W$N%H%i%U%#%C%/$,(B
$BIT0BDj$G$"$l$P!"(B7 $B>O$N(B FAQ $B$NCf$K$"$k(B
<A HREF="IP-Masquerade-HOWTO-7.html#MTU-issues">MTU $BLdBj(B</A>
$B$rFI$`$3$H$r$*>)$a$7$^$9!#(B
FAQ $B$NCf$K$O!"$$$^$^$GB?$/$N%f!<%6!<$NLr$KN)$C$?$h$&$K!"$"$J$?(B
$B$NLr$KN)$D9`L\$,$-$C$H$"$k$3$H$G$7$g$&!#(B
<P>
<P>
</LI>
</UL>
<P>
<P>
<HR>
<A HREF="IP-Masquerade-HOWTO-6.html">$B<!$N%Z!<%8(B</A>
<A HREF="IP-Masquerade-HOWTO-4.html">$BA0$N%Z!<%8(B</A>
<A HREF="IP-Masquerade-HOWTO.html#toc5">$BL\<!$X(B</A>
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