Load balancing with the Session Initiation Protocol proxy server

load balancer for IBM WAS can help maximize the potential of the Web site by providing a powerful, flexible, and scalable solution to peak-demand problems. Configuration of a load balancer is critical to prevent any single points of failure at Session Initiation Protocol (SIP) proxy. Configuration of a load balancer is required when more than one SIP proxy is deployed.

Before beginning, complete these tasks.

• Install load balancer for IBM WAS. See the information provided in the Edge Components Information Center. This information center is available on the WAS Library page.

• From the load balancer for IBM WAS, complete the steps for setting up server machines for load balancing. Ensure set up a loopback address for the operating system. See the load balancer Administration Guide in the Edge Components Information Center.

• Start the Session Initiation Protocol (SIP) proxy server.

Complete these steps to integrate the SIP proxy server with the Load Balancer.

 

1. Start the load balancer.

   1. From the command prompt, type dsserver start .

   2. Then type lbadmin to start the admin console for the load balancer.

   3. From the admin console, right click Dispatcher , and then select Connect to Host.

   4. Right click on the hostname and select Start Executor.

2. Start the configuration wizard for the load balancer.

   1. Select default host.

   2. Type a cluster address. You should not be able to ping the cluster address before the Executor starts. Specify this same value for host when creating a user-defined port.

   3. Type a port number, such as 5060.

      Specify this same value for port when creating a user-defined port.

   4. Add servers to the port. Add each server to which the load balancer will proxy traffic. In the configuration, the load-balanced server is the proxy server for the configuration.

   5. Start an advisor by typing the name of the advisor. For example, for HTTP traffic, start the HTTP advisor. For SIP traffic, start the SIP advisor. The advisor tells the manager whether or not a specific port is accepting traffic.

3. Alias the cluster address on the SIP proxy server loopback adapter. See the topic entitled "Setting up server machines for load balancing" in the load balancer for WAS Administration Guide, V6.1.

4. Set an IP sprayer from the admin console.

   1. From the admin console ...

      Servers > Server Types > WebSphere proxy servers > proxy_server_name > SIP proxy server settings > SIP proxy settings.

   2. Under General Properties, in the IP sprayer configuration section, select the checkbox for the IP sprayer from which you want the SIP proxy server to receive traffic: Enable TCP sprayer , Enable SSL sprayer, or Enable UDP sprayer.

   3. Enter a value for the Host . This is the host for the load balancer.

   4. Enter a value for the Port . This is the port for the load balancer.

   5. Click Apply, and then click Save.

5. Define SIP proxy server custom properties from the admin console.

   1. From the admin console ...

      Servers > Server Types > WebSphere proxy servers > proxy_server_name > SIP proxy server settings > SIP proxy settings.

   2. In the Additional Properties section, click Custom properties.

   3. Specify a value for these SIP proxy custom properties, and then click OK.

      These settings are now available from the SIP proxy settings page in the admin console and do not require that a custom property be set, however the custom properties are supported. If the custom property is set, the value of the custom property is used even if we set the value in the admin console.

      • LBIPAddr
      • SIPAdvisorMethodName

6. Set up a loopback address that represents the IP address for the load balancer. See the load balancer documentation for information about setting up loopback addresses.

7. Create a user-defined port from the WAS admin console.

   1. From the admin console ...

      Servers > Server Types > WebSphere proxy servers > proxy_server_name Ports > New.

   2. Select User-defined port.

   3. Enter SIP_LB_Address for the Port Name.

   4. Enter a value for the Host . This is the host for the load balancer.

   5. Enter a value for the Port . This is the port for the load balancer.

   6. Enter a value for PROXY_SIP_ADDRESS

      This is the actual hostname for the proxy server machine.

   7. Click Apply, and then click Save.

8. Modify the SIP proxy transports from theadmin console.

   1. From the admin console, click From the admin console ...

      Servers > Server Types > WebSphere proxy servers > proxy_server_name > SIP container transport chains > UDP_SIP_PROXY_CHAIN > UDPInbound Channel.

   2. Under SIP proxy transports, modify UDP_SIP_PROXY_CHAIN .

   3. From the Port drop-down list, select SIP_LB_Address

   4. Click Apply, and then click Save.

9. Restart the proxy server to save the changes.

 

Related tasks

Install a Session Initiation Protocol proxy server

 

Related

SIP proxy server custom properties

 

Related information

Edge Components Information Center