Preparing Linux systems for installation

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

Before you begin

Because WebSphere® Application Server is a prerequisite of IBM Business Process Manager, you must complete all the required preparation steps in the Preparing Linux systems for installation topic in the WebSphere Application Server information center.

Ensure that you have Mozilla Firefox installed at version 3.5.x.x or higher.

About this task

Because certain steps are specific to a version of the operating system, all steps might not apply to your environment. If no qualifier is provided for a particular step, complete the step for all versions of the operating system. To install Installation Manager on Red Hat Enterprise Linux 6.0 (64-bit), see Unable to install Installation Manager on RHEL 6.0 (64-bit).

Note: Cognos bundles an alternate version of the libfreebl3.so library for Red Hat Enterprise Linux 6.0 (64-bit). Ensure that you preinstall this system library that is required for other utilities.

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

1. 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:

   # - stack - max stack size (KB)
   * soft stack 32768
   * hard stack 32768
   # - nofile - max number of open files
   * soft nofile 65536
   * hard nofile 65536
   # - nproc - max number of processes
   * soft nproc 16384
   * 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 the operating system for product installation in the WebSphere Application Server information center.
2. 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.
3. If you are planning to install DB2 Express as part of the installation process, ensure that you have administrative (root) privileges. As a root user, you must also ensure that all kernel requirements are met before the DB2 Express installation begins. You can locate the current values by parsing the output of the ipcs -l command. To change the values, add the following lines, in the following order, to the /etc/sysctl.conf file:

   kernel.shmmni=4096 
   kernel.shmmax=4294967296 
   kernel.shmall=8388608 
   #kernel.sem=<SEMMS><SEMMNS><SEMOPM><SEMMNI>
   kernel.sem=250 256000 32 4096 
   kernel.msgmni=16384 
   kernel.msgmax=65536 
   kernel.msgmnb=65536

   Reboot the system
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
   Red Hat Enterprise Linux 6	ksh-version.rpm Korn shell

   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.