Ubuntu Virtual Servers

(This section is under construction.)

The idea is to use a URL (such as worldvista.myoffice.org) for your site (that is registered on an Internet DNS (Domain Name Server)) to access the VistA server, instead of using the actual IP address of the server. Most configurations involve a LAN, and usually the registered URL generally points not to the (LAN) IP address of the server computer (within the LAN), but to the (WAN, or Internet) IP address of the router itself. Therefore, communications arriving at the router must be forwarded properly from the router (connected to the Internet) to the server (within the LAN).

NAT

Consumer-grade routers generally use NAT port-forwarding to send traffic that arrives at the router to a specific server within the LAN (such as the one hosting the VistA server). Certain types of traffic can be designated as flowing over "ports" and (in the simplest scenario) a specific server can be designated as the destination on the LAN to which all the traffic over a specific port will be sent.

Your router's configuration utility (often accessible from a web browser) allows you to configure "NAT port forwarding" so that traffic arriving at a certain port (such as port 22) will be "forwarded" to a specific server on the LAN (which will have its own unique IP address within the LAN).

With Astronaut, all communications are sent through a secure SSH tunnel. By convention, SSH communications are usually sent on port 22 (but that can be changed). If you only have one SSH server on your LAN, using port 22 will be fine. However, if there are more than one SSH servers on your LAN, or if you want a modicum of greater security, then a different port can be used for SSH.)

• Copy and edit a configuration file in the Apache2 sites-available folder.

cd /etc/apache2/sites-available
sudo cp default worldvista
sudo kate worldvista

• Edit the virtual host file so that it looks like:

<VirtualHost *:22>
ServerAdmin webmaster@worldvista.myoffice.org
DocumentRoot /opt/worldvista/EHR
ServerName worldvista.myoffice.org
ServerAlias www.worldvista.myoffice.org worldvista.myoffice.org
</VirtualHost>

where worldvista.myoffice.org is an example URL for your server (use your own, of course)

• Restart Apache2:

sudo /etc/init.d/apache2 restart

• Make sure your router forwards port 22 to the (static) IP address (on your LAN) at which the computer (or virtual machine) hosting the VistA server resides.

Changing the SSH port

(Under construction).

• See Ubuntuguide's section on SSH in the meantime.