How to Configure Multiple CA SDM Web Engines on Application Servers?

In CA SDM Advanced Availability architecture, you normally only one webengine/domsrvr pair on each Application server. However, in certain CA SDM environments, you may want to have more than one webengine/domsrvr pair for each of your Applicatiton servers, This will help in distributing the server load without the need to configure additional hardware or virtual machines.
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Overview
In CA SDM Advanced Availability architecture, you normally only one webengine/domsrvr pair on each Application server. However, in certain CA SDM environments, you may want to have more than one webengine/domsrvr pair for each of your Applicatiton servers, This will help in distributing the server load without the need to configure additional hardware or virtual machines.
F5 load balancers can only distribute the load across servers, but not across webengines. The only way to distribute a load across webengines is to use a web director within CA SDM itself. Typically in an advanced availability environment, if you want to use more than one webengine/domsrvr pair on your application servers behind an F5 Load Balancer , you will distribute the F5 load balancers across servers, and then have a web director on each application servers to distribute that load across the web engines on that specific server. To do this, you must configure the CA SDM systems as following: 
Example Use Case
:
Consider that your CA SDM environment has the following server Configuration: 
  • Background Server
  • Standy Server
  • 3 Application Servers (APP1, APP2 and APP3)
  • F5 load balancer dividing the load among APP1, APP2 and APP3
  • One domsrvr/webengine pair on each APP server
Given the above setup configuration, your goal is to distribute, let us say, 4-domsrvr/webengine pairs on each APP server. Navigate to Administration tab, System, Configurations, and edit the configuration that you are using by performing the following on each APP server:
  1. Create a Web Director.
  2. Edit the existing webengine (the original one) and set it to use the new web director on that specific server.
  3. Add 2 more Object Managers.
  4. Add 2 more Web Engines, setting each one to use its own appropriate domsrvr on that specific server. Also, configure the web engines to use the Web Director you created in step-1.
  5. Save the configuration.
  6. Run pdm_configure on the BG (you will need to fail over to the SB first), SB (you will need to fail back to the original BG first), APP1, APP2 and APP3 servers in that order.
  7. Point the F5 Load Balancer to distribute the load between the 3 Web Directors on the APP servers.
 
The configuration will look like this visually:
APP1
  • WebDirector1
  • Domsrvr1
  • Domsrvr2
  • Domsrvr3
  • Webengine1 (Behind WebDirector1) (Set to use Domsrvr1)
  • Webengine2 (Behind WebDirector2) (Set to use Domsrvr2)
  • Webengine3 (Behind WebDirector2) (Set to use Domsrvr3)
APP2
  • WebDirector1
  • Domsrvr1
  • Domsrvr2
  • Domsrvr3
  • Webengine1 (Behind WebDirector1) (Set to use Domsrvr1)
  • Webengine2 (Behind WebDirector2) (Set to use Domsrvr2)
  • Webengine3 (Behind WebDirector2) (Set to use Domsrvr3)
APP3
  • WebDirector1
  • Domsrvr1
  • Domsrvr2
  • Domsrvr3
  • Webengine1 (Behind WebDirector1) (Set to use Domsrvr1)
  • Webengine2 (Behind WebDirector2) (Set to use Domsrvr2)
  • Webengine3 (Behind WebDirector2) (Set to use Domsrvr3)
 
 
F5 Load Balancer configuration will be as follows:
  • APP1 →WebDirector
    • Webengine1
    • Webengine2
    • Webengine2
  • APP2→WebDirector
    • Webengine1
    • Webengine2
    • Webengine2
  • APP3 →WebDirector
    • Webengine1
    • Webengine2
    • Webengine2