Mac 10.7 Server syslogd listen to external connections

First make a backup of the plist, then do the following:

Convert it to XML so it’s editable:

sudo plutil -convert xml1 /System/Library/LaunchDaemons/com.apple.syslogd.plist

Edit the file; I used pico with this command (you can also use TextWrangler, etc.):

sudo pico /System/Library/LaunchDaemons/com.apple.syslogd.plist

You need to insert this key:

<key>NetworkListener</key>
 <dict>
        <key>SockServiceName</key>
        <string>syslog</string>
        <key>SockType</key>
        <string>dgram</string>
 </dict>

Convert the plist back to binary format:

sudo plutil -convert binary1 /System/Library/LaunchDaemons/com.apple.syslogd.plist

Unload and reload syslogd:

sudo launchctl unload /System/Library/LaunchDaemons/com.apple.syslogd.plist sudo launchctl load /System/Library/LaunchDaemons/com.apple.syslogd.plist

Afterwards check Console.app for incoming logs from your router, etc.