Clustering › How to Set Up Load Balancing › How to Update the httpd.conf File

How to Update the httpd.conf File

Updating the httpd.conf file is required to set up load balancing.

1. In the Apache HTTP Server installation directory, modify the conf/httpd.conf file to include the following specifications:

   Listen 89
   LoadModule jk_module modules/mod_jk.so
   JkWorkersFile conf/workers.properties
   

   <VirtualHost *:89>
    ServerName load balancer host name
   

    JkMountFile conf/uriworkermap.properties
    JkLogFile logs/mod_jk.log
    JkLogLevel debug
   </VirtualHost>
   

2. In the specifications in Step 1, note the following lines:

   JkLogFile logs/mod_jk.log
   JkLogLevel debug
   

   You can optionally replace them with the following lines, to modify the mod_jk.log file on your production server to record only critical errors and to enable log automatic rollover when its file size reaches 10 MB:

   JkLogFile "|bin/rotatelogs.exe logs/mod_jk.log.%Y-%m-%d-%H_%M_%S 10M"
   JkLogLevel emerg
   

3. Also for the specifications in Step 1, for every VirtualHost port, add a Listen directive with the port number.

   For example, suppose you have defined a virtual host at port 89, as follows:

   <VirtualHost *:89>
   

   In that case, add the Listen directive for this port in the httpd.conf file, for example:

   Listen 89
   

   Note: The commonly used port is 89.

   This specification enables the Apache HTTP Server to listen on this port and accept incoming requests.

4. In the httpd.conf file, change the Default Type from text/plain to text/html.

   Note: This setting works well on most browsers. If you experience any difficulty with system performance or display quality after changing this option, return it to its original value.

5. Also in your browser settings, set the proper values for the ServerAdmin and ServerName options, if you have not done so.
6. Restart the Apache service, as follows:
   1. Open the Apache Service Monitor.
   2. Highlight the service to be restarted.
   3. Click Restart.
7. Test by accessing the link http://loadbalancerhostname:89/wl or any other context for CA Workflow and http://hostname:89/usm for Service View.

   Here, hostname specifies the load balancer computer, that is, the computer on which the Apache HTTP Server is configured for load balancing. For example, if the host name of the load balancer computer is ABC, then the link is http://ABC:89/wl.

8. Check the mod_jk.log file under the logs folder in the Apache directory to determine which jvmRoute node was called. An example follows:

   found worker HOST1__USMView (HOST1__USMView) for route COMPUTER1__USMView and partial sessionid
   

9. Disable the HTTP ports of the cluster computers, so that users are routed directly to the load balancer computer rather than directly to a cluster, as follows:
   1. In the server.xml files of each cluster computer, comment the connector tag which has the HTTP port information. This port is the startup node provided during installation, typically 8080 for Service View and 8090 for CA Workflow.
   2. On the CA Service Catalog GUI, click Administration, Configuration, Server Information.
   3. Replace the server host name and port number with the load balancer host name and port number.
   4. Recycle Windows services of the clusters whose server.xml files were changed.
   5. On the CA Service Catalog GUI, click Administration, Configuration, Workflow.
   6. If CA Workflow is also clustered, perform this step; otherwise, skip this step and go to the next step.

      Replace the CA Workflow host name and port number with the load balancer host name and port number.

   7. Click the Configure button.

      This action update the CA Workflow actors with the new URLs.

   8. Recycle the Windows services of the clusters whose server.xml files were changed.