Apple Mac OS X Server manual Port Mapping, Viewing the NAT Service Log

Port Mapping

You can configure port mapping by adding a redirect_port directive to the configuration file passed to the natd process. You can accomplish this by editing the plist version of the configuration file /etc/nat/natd.plist. This file is in turn processed by the serveradmin tool, and used to create the configuration file /etc/nat/ natd.conf.apple, which is passed to the natd process. See the natd man page for details about configuring natd.

Note: Don’t edit the /etc/nat/natd.conf.apple file directly, since it is regenerated every time the serveradmin start nat command is executed.

To configure NAT to use the port mapping rule redirect_port tcp 1.2.3.4:80 80, you would add the following lines to /etc/nat/natd.plist, inside the configuration dictionary:

<key>redirect_port</key> <array>

<dict>

<key>proto</key>

<string>tcp</string>

<key>targetIP</key>

<string>1.2.3.4</string>

<key>targetPortRange</key>

<string>80</string>

<key>aliasPortRange</key>

<string>80</string>

</dict>

</array>

You can then confirm those settings using the serveradmin tool:

$ sudo serveradmin settings nat

...

nat:redirect_port:_array_index:0:proto = "tcp"

nat:redirect_port:_array_index:0:targetPortRange = "80"

nat:redirect_port:_array_index:0:aliasPortRange = "80"

nat:redirect_port:_array_index:0:targetIP = "1.2.3.4" Control-D

Viewing the NAT Service Log

You can use tail or any other file listing tool to view the contents of the NAT service log.

To view the latest entries in the log:

$ tail log-file

You can use the serveradmin getLogPaths command to see where the current NAT service log is located.

Chapter 14 Working with Network Services

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