A basic installation of GroupWise WebAccess requires the WebAccess Agent and the WebAccess Application, as shown in the following diagram. The WebPublisher Application is also required if you plan to use GroupWise WebPublisher.
Figure 53-1 A Basic Installation of GroupWise WebAccess
Depending on your needs, it might be necessary for you to add additional WebAccess Agents or to have multiple Web servers running the WebAccess Application and WebPublisher Application.
GroupWise WebAccess is designed to allow one installation of the WebAccess Application and WebPublisher Application to support multiple WebAccess Agents, as shown in the following diagram.
Figure 53-2 Multiple WebAccess Agents
There are various reasons why you might want to add additional WebAccess Agents, including:
Improving reliability: One WebAccess Agent might provide sufficient access and performance, but you want to protect against downtime that would occur if the WebAccess Agent became unavailable because of server failure or some other reason. Installing more than one WebAccess Agent enables you to set up failover support to make your system more reliable.
Improving performance: The WebAccess Agent is designed to be close to the GroupWise databases. It requires direct access to a domain database and either direct access to post office databases or TCP/IP access to the Post Office Agents. For best performance, you should ensure that the WebAccess Agent is on the same local area network as the domain and post offices it needs access to. For example, in most cases you would not want a WebAccess Agent in Los Angeles accessing a post office in London.
Improving availability: The WebAccess Agent has 12 threads assigned to process user requests, which means that it can process only 12 requests at one time regardless of the number of users logged in. If necessary, you can increase the number of threads allocated to the WebAccess Agent, but each thread requires additional server memory. If you reach a point where WebAccess is unavailable to users because thread utilization is at a peak and all server memory is being used, you might need to have several WebAccess Agents, installed on different network servers, servicing your post offices. For information about changing the number of allocated threads, see Section 54.1, Configuring the WebAccess Agent.
As with the WebAccess Agent, you can also install the WebAccess Application and WebPublisher Application to multiple Web servers, as shown in the following diagram.
Figure 53-3 The WebAccess Application and WebPublisher Application Installed to Multiple Web Servers
Some reasons for wanting to use this type of configuration include:
Enabling WebAccess users on an intranet to access GroupWise through an internal Web server and WebAccess users on the Internet to access GroupWise through an exposed Web server.
Increasing Web server performance by balancing the workload among several Web servers, especially if you are using the Web server for other purposes in addition to GroupWise WebAccess.
Hosting WebAccess (the WebAccess Application) on one Web server for your GroupWise users and WebPublisher (the WebPublisher Application) on another Web server for public Internet use.
If necessary, you can use multiple WebAccess Agents in this configuration, as shown below.
Figure 53-4 The WebAccess Application on One Web Server, and the WebPublisher Application on Another