Preparing Linux systems for installation

Before you can install IBM® Business Automation Workflow, you must prepare your Linux operating system.

Complete the following steps on your Linux® system before installing Business Automation Workflow:

1. Because WebSphere® Application Server is a prerequisite of Business Automation Workflow, complete all the required preparation steps in the Preparing Linux systems for installation topic in the WebSphere Application Server documentation.
   Note: Make sure the X Window System (X11) is installed.
2. Increase the allowable stack size, number of open files, number of processes, and file size 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 - maximum stack size (KB)
   user_name soft stack 32768
   user_name hard stack 32768
   # - nofile - maximum number of open files
   user_name soft nofile 65536
   user_name hard nofile 65536
   # - nproc - maximum number of processes
   user_name soft nproc 16384
   user_name hard nproc 16384
   # - fsize - maximum file size
   user_name soft fsize 6291453
   user_name hard fsize 6291453

   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 and the current maximum file size by using ulimit -f. 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 documentation.
3. Check for the existence of a file named /etc/security/limits.d/90-nproc.conf or /etc/security/limits.d/20-nproc.conf, which overrides the nproc value set in the limits.conf file. If this file exists, edit it and set the same nproc values that you specified in limits.conf.
4. Check for the existence of a file named /etc/profile, which overrides the nofile values set in the limits.conf file. If the ulimit -n values exist in the /etc/profile file, edit it and set the same nofile values that you specified in limits.conf.
5. If you are using Red Hat Enterprise Linux 5 (deprecated), 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 

6. On Linux on System z, if you plan to use the Installation Manager graphical interface to install IBM Business Automation Workflow, install the libgtk-2_0-0-32bit and libgthread-2_0-0-32bit libraries.
   The following example shows how to install these using the zypper command:

   zypper install libgtk-2_0-0-32bit
   zypper install libgthread-2_0-0-32bit

   For additional information, see X libraries required by IBM Installation Manager on Linux for System z
7. Set the umask value to 077 using the following command:
   • umask 077

   The value 077 is the most restrictive value that IBM Business Automation Workflow 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
8. On Red Hat Enterprise Linux 5 systems, disable SELinux, or set it to a permissive mode.
9. Restart the computer.
10. Complete the steps in Tuning Linux systems.
11. 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.
12. If you are using DB2, make sure that all your DB2 parameters meet the DB2 naming rules.