Building and Configuring a Zeus Web Server Cluster with Load Balancing

Building a Zeus Web Server Cluster and Configuring Load Balancing

Zeus Web Server (ZWS) is a commercial-grade web server whose core advantages include built-in load balancing and health monitoring capabilities for backend servers. While early versions of Nginx also supported load balancing, their active health check features were limited. High-end hardware load balancers (e.g., F5 BIG-IP, Radware) are feature-rich but costly, targeting large enterprises. According to official test data, a ZWS cluster can handle tens of thousands of concurrent connections, meeting the performance needs of most small-to-medium businesses and internet applications while effectively controlling costs.

Cluster Architecture Overview

A typical ZWS cluster consists of two components:

• Administrator Host: Manages unified configuration, monitoring, and traffic distribution for the cluster.
• Real Server: Application servers that actually process HTTP requests.

The Administrator Host communicates with Real Servers via TCP/IP. The Administrator Host can also act as a Real Server. ZWS uses the Round Robin algorithm by default to distribute client requests. Combined with a High Availability (HA) solution, this enables a highly available web server cluster.

Detailed Configuration Steps

1. Preparation

Install Zeus Web Server on all hosts designated as Real Servers.

2. Register Backend Servers

On each backend server, run the registration script to add it to the Administrator Host's management list.

$ZEUSHOME/web/bin/registerwithadminserver

The script runs interactively, requiring:

• Administration Server Hostname: Hostname or IP address of the Administrator Host.
• Administration Server Port: Port of the Administrator Host (default 9090).
• Administration Server Password: Administrator password.

Successful registration output example:

This Web Server has now been successfully registered with the
specified Zeus Administration Server.
It will now be visible in the Administration Server
User Interface (on the Machines Configuration page)
as askwan:9080.
Registration with admin.askwan.com:9090 was successful.
Now restarting this server…
Zeus Web Server restarted.

Note: Registration restarts the ZWS service on the current server. Warnings like "basename: too few arguments" can usually be ignored.

3. Add Cluster Servers on the Administrator Host

Log into the ZWS administration interface on the Administrator Host. Navigate to the Cluster Configuration page. Use the "Adding a Web Server to the Cluster" function to add registered backend servers.

Key information required:

• Machine name: Hostname of the backend server.
• Port: ZWS service port on the backend server (default 9080).

Repeat this step for all backend servers to complete the basic cluster setup.

Configuration Recommendations and Notes

• Health Checks: The ZWS Administrator Host continuously monitors backend server status. If a server fails, traffic is automatically redirected to healthy servers.
• Session Persistence: For applications requiring session state, enable the Session Affinity feature in the cluster configuration.
• Version Note: This guide is based on Zeus Web Server 4.3 (released 2004). Please note this product is no longer maintained. Many of its concepts and features have been adopted and evolved by modern load balancers (e.g., Nginx Plus, HAProxy, cloud provider LB services). This article serves primarily as a reference for historical technical architecture.