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shorewall6-nat(5)

NAME

   nat - Shorewall6 one-to-one NAT file

SYNOPSIS

   /etc/shorewall6/nat

DESCRIPTION

   This file is used to define one-to-one Network Address Translation
   (NAT).

       Warning
       If all you want to do is simple port forwarding, do NOT use this
       file. See http://www.shorewall.net/FAQ.htm#faq1[1].

   The columns in the file are as follows (where the column name is
   followed by a different name in parentheses, the different name is used
   in the alternate specification syntax).

   EXTERNAL - {address|?COMMENT}
       External IP Address - this should NOT be the primary IP address of
       the interface named in the next column and must not be a DNS Name.

       If you put ?COMMENT in this column, the rest of the line will be
       attached as a comment to the Netfilter rule(s) generated by the
       following entries in the file. The comment will appear delimited by
       "/* ... */" in the output of "shorewall show nat"

       To stop the comment from being attached to further rules, simply
       include ?COMMENT on a line by itself.

   INTERFACE - interfacelist[:[digit]]
       Interfaces that have the EXTERNAL address. If ADD_IP_ALIASES=Yes in
       shorewall6.conf[2](5), Shorewall will automatically add the
       EXTERNAL address to this interface. Also if ADD_IP_ALIASES=Yes, you
       may follow the interface name with ":" and a digit to indicate that
       you want Shorewall to add the alias with this name (e.g.,
       "eth0:0"). That allows you to see the alias with ifconfig.  That is
       the only thing that this name is good for -- you cannot use it
       anywhere else in your Shorewall configuration.

       Each interface must match an entry in shorewall6-interfaces[3](5).
       Shorewall allows loose matches to wildcard entries in
       shorewall6-interfaces[4](5). For example, ppp0 in this file will
       match a shorewall6-interfaces[3](5) entry that defines ppp+.

       If you want to override ADD_IP_ALIASES=Yes for a particular entry,
       follow the interface name with ":" and no digit (e.g., "eth0:").

   INTERNAL - address
       Internal Address (must not be a DNS Name).

   ALLINTS - [Yes|No]
       If Yes or yes, NAT will be effective from all hosts. If No or no
       (or left empty) then NAT will be effective only through the
       interface named in the INTERFACE column.

       This column was formerly labelled ALL INTERFACES.

   LOCAL - [Yes|No]
       If Yes or yes, NAT will be effective from the firewall system

FILES

   /etc/shorewall6/nat

SEE ALSO

   http://www.shorewall.net/NAT.htm[5]

   http://www.shorewall.net/configuration_file_basics.htm#Pairs[6]

NOTES

    1. http://www.shorewall.net/FAQ.htm#faq1
       http://www.shorewall.net/FAQ.htm#faq1

    2. shorewall6.conf
       http://www.shorewall.net/manpages/shorewall.conf.html

    3. shorewall6-interfaces
       http://www.shorewall.net/manpages/shorewall6-interfaces.html

    4. shorewall6-interfaces
       http://www.shorewall.net/manpages/shorewall-interfaces.html

    5. http://www.shorewall.net/NAT.htm
       http://www.shorewall.net/NAT.htm

    6. http://www.shorewall.net/configuration_file_basics.htm#Pairs
       http://www.shorewall.net/configuration_file_basics.htm#Pairs



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