13
Two-Armed NAT Mode
o
The main purpose of the WebMux is to balance IP traffic amongst multiple web, or other,
servers. The diagram above shows a NAT installation with two WebMux units. In this example,
one WebMux is serving as the primary, and the other is serving as the secondary, or backup,
providing a fault tolerant solution (also called High Avaliability or HA).
In order for the web servers to share the incoming traffic, the WebMux must be connected to the
network. There may be two or four load balanced interfaces on the WebMux. The left-side,
load balanced interfaces connect to the Router LAN. This is the network to which the Internet
router is connected. The right-side, load balanced interfaces are connected to the Server LAN.
This network connects to all of the web servers. The WebMux routes traffic between these two
networks.
Next, virtual farms must be configured on the WebMux. A virtual farm is a single representation
of the servers to the clients. A farm consists of a group of servers that serve the same
domain,
website or services.
For example, to configure a farm (or virtual farm) to serve www.avanu.com:
First, Server 1 and Server 2 would each need the website www.avanu.com configured
on them and HTTP/HTTPS services started; and
Second, a farm on the WebMux is defined with Server 1 and Server 2 in it. The servers
could be setup to either share the traffic (load balancing), or setup as a primary server
