DirectAdmin can run on a LAN/NAT, many of our clients do it, even though it's not "officially" supported.
The only reason it's unofficial is due to the non-standard way of loading the external IP into the internal/LAN device. Operating should still be fine.
1.Type the following before running the setup.sh:
echo 1 > /root/.lan
to have DA download the update.tar.gz and license.key more easily (skips the --bind-address option).
2.You'll need to make sure that the licensed IP is in the device. This guide can help with that.
3.Install DirectAdmin normally, using the setup.sh
When it asks for which ethernet device, make sure you pick the device that holds the licensed IP (often eth0:0 or venet0:0).
Enter the license IP, and not the LAN ip when asked.
After the install is done, make sure you complete steps 4 and 5 below.
4.Link the LAN IP to your public IP using the Linked IP feature.
With this feature, you'd do the following:
Add the LAN IP to DA's IP manager. Don't assign it to any Users or Domains.
View the details of the external IP: Admin Level -> IP Manager -> Click the public/external IP.
Link the internal IP to the external IP: Select the LAN IP from the drop down.
Only select Apache, do not select DNS
5.Add the following value to your directadmin.conf, and restart DA:
where you'd replace 192.168.1.2 with the LAN IP value that should be used for outbound connections.
6.You must disable popb4smtp via the exim.conf if all incoming IPs are your router's IP (always the same). If inbound IPs are external, then this is not requierd. If you type "who", check which IP shows up as your inbound ssh IP. If it's the router IP, disable pophosts.