Preparing Linux systems for installation

Before you can install IBM® Business Process Manager, you must prepare your Linux operating system.

Complete the following steps on your Linux system before installing IBM Business Process Manager:

1. Because WebSphere® Application Server is a prerequisite of IBM Business Process Manager, complete all the required preparation steps in the Preparing Linux systems for installation topic in the WebSphere Application Server information center.
2. Increase the allowable stack size, number of open files, and number of processes by adding the following lines to the end of the /etc/security/limits.conf file or changing the values if the lines already exist. In this example, user_name is the name of the user that runs WebSphere Application Server:

   # - stack - max stack size (KB)
   user_name soft stack 32768
   user_name hard stack 32768
   # - nofile - max number of open files
   user_name soft nofile 65536
   user_name hard nofile 65536
   # - nproc - max number of processes
   user_name soft nproc 16384
   user_name hard nproc 16384

   Save and close the file, and log off and log in again. You can check the current maximum number of open files by using ulimit -n. The ulimit requirement is dynamically calculated at installation time and might need to be larger based on the options you select. For more information about this setting, run man limits.conf or see the topic Preparing Linux systems for installation in the WebSphere Application Server information center.
3. Check for the existence of a file named /etc/security/limits.d/90-nproc.conf, which overrides the nproc value set in the limits.conf file. If the 90-nproc.conf file exists, edit it and set the nproc values that are specified in the previous step.
4. Install the following packages for your operating system:

   Option	Description
   Red Hat Enterprise Linux 5	libXp-1.0.0-8 rpm-build-4.4.2-37.el5

   You can also install a later release of any of these packages if there are new packages as errata. If you have additional packages that are specific to your hardware, install them.
   The following command example shows how to use the default package manager on supported Linux distributions.

   • Red Hat Enterprise Linux 5:

     yum install libXp rpm-build 

5. Set the umask value to 077 using the following command:
   • umask 077
   The value 077 is the most restrictive value that IBM Business Process Manager will tolerate. You can optionally choose to set a less restrictive umask value for the following access levels:

   • 037 for read-only access for a group of human administrators and tools
   • 027 for read and write access for a group of human administrators and tools
   • 007 for read, write, and execute access for a group of human administrators and tools
6. On Red Hat Enterprise Linux 5 systems, disable SELinux, or set it to a permissive mode.
7. Restart the computer.
8. Complete the steps in Tuning Linux systems.
9. Ensure all servers involved are set to the same time. Use the same network time protocol for all servers on all cluster nodes, including application, support, and database clusters. A time mismatch will cause erratic behavior, including duplicate system tasks.
10. If you are using DB2, make sure that all your DB2 parameters meet the DB2 naming rules.