Sun Java System Access Manager Policy Agent 2.2 Guide for Microsoft Internet Information Services 6.0

Enabling Load Balancing

Various properties in the web agent AMAgent.properties configuration file can be used to enable load balancing. Edit the properties that apply, according to the location of the load balancer or load balancers in your deployment, as follows:

Load Balancer in Front of Access Manager

When a load balancer is deployed in front of Access Manager and a web agent interacts with the load balancer, the following properties must be edited:

com.sun.am.naming.url
com.sun.am.policy.am.login.url
com.sun.am.load_balancer.enable

Example 6–3 Property Settings: Load Balancer in Front of Access Manager

This example illustrates property settings in the web agent AMAgent.properties configuration file that can be used to enable load balancing:

com.sun.am.naming.url = LB-url/amserver/namingservice
com.sun.am.policy.am.login.url = LB-url/amserver/UI/Login
com.sun.am.load_balancer.enable = true

where LB-url represents the load balancer URL. The following example is a conceivable load balancer URL:

http://hostname.example.com:8080

Load Balancer in Front of Web Agent

In many cases, when a load balancer is deployed in front of the web agent only the following property must be set:

com.sun.am.policy.agents.fqdnMap

Example 6–4 Property Settings: Load Balancer in Front of Web Agent

com.sun.am.policy.agents.fqdnMap = valid|LB-hostname

where LB-hostname represents the name of the machine on which the load balancer is located.


However, if SSL-termination or a proxy server is used in the deployment, all the following properties in the web agent AMAgent.properties configuration file should be set in addition to the preceding property:

com.sun.am.policy.agents.config.override_protocol
com.sun.am.policy.agents.config.override_host
com.sun.am.policy.agents.config.override_port
com.sun.am.policy.agents.config.agenturi.prefix

This example illustrates how properties can be set to enable load balancing when the protocol, hostname, and port number of the load balancer differ from that of the web agent. However, if the load balancer and the web agent share one of these characteristics, such as the protocol or hostname, then the respective property would be left blank instead of being assigned a value of true.

com.sun.am.policy.agents.config.override_protocol = true
com.sun.am.policy.agents.config.override_host = true
com.sun.am.policy.agents.config.override_port = true
com.sun.am.policy.agents.config.agenturi.prefix = LB-url/amagent

where LB-url represents the load balancer URL. The following example is a conceivable load balancer URL:

http://hostname.example.com:8080

Load Balancers in Front of Both the Web Agent and Access Manager

This scenario is simply a combination of the scenarios described in the preceding sections. See Load Balancer in Front of Access Manager and Load Balancer in Front of Web Agent.