How about learning details to install Registry Services on AIX and zLinux systems? Get to know some examples!

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*With the collaboration and review of Maristela Salvatore @soaresm

Although they are not as user-friendly as Windows systems, environments such as IBM AIX and zLinux systems provide you with highly reliable, secure and specialized systems. For instance, IBM AIX system was recently used by the Curiosity rover sent to Mars on an exploratory endeavor. You can follow Curiosity news over its twitter @marscuriosity

These specialized systems, depending on their use, require a number of customizations so you can get their best performance and functionality level. For example, IBM AIX comes by default with the Korn Shell (Ksh) command-line interface, which does not provide you with the auto-complete feature. To make this command-line interface as user-friendly as possible, you can customize the AIX environment to use Bash (Bourne-again Shell), which enables the use of auto-complete feature.

In terms of performance, IBM AIX has a limited number of processes running in parallel, which can either affect the application performance or make it stop working altogether. For cases such as this one, variables need their values increased or unlimited.

Example1: for setting unlimited number of processes running in parallel

#chdev -l sys0 -a maxuproc=-1

When you install Registry Services on these highly specialized systems, you must also customize them to obtain the best performance. Such customizations apply to both DB2 and WebSphere Application Server, respectively the DB management system and the application server that Registry Services currently supports.

Among all possible customizations, you can set environment variables whose default values may cause you some issues or performance degradation to Registry Services. For example, set the minimum and maximum memory size so that DB2 database system has its better performance. For this case, the recommended values can be set using the following command example:

Example2: recommended values for memory size on IBM AIX

# vmo -p -o minfree=4906 -o maxfree=5418

minfree:

DB2 recommended value:

– 4096 for memory less than 8 GB

maxfree:

DB2 Recommended value:

– minfree + 512

For DB2 and WebSphere Application Server, the default values of those systems does not provide the best results for Registry Services performance. Luckily, both DB2 and WAS are very flexible and customizable. In this case, you can reach a good performance tuning by customizing values such as JVM memory, maximum number of connections, and others.

This article from developerWorks shows some of the performance customization that can be done on AIX systems: https://www.ibm.com/developerworks/mydeveloperworks/blogs/timdp/entry/performance_tuning_websphere_application_server_7_on_aix_6_1179?lang=en

At this point, you might be asking: “ where do I get information for customizing Registry Services installation on such highly specialized systems?”. Well, our experience has shown two good sources:

- Redbooks

- Networking

You should not be limited to them, but we can tell you that IBM Redbooks provided us with valuable information to get started with AIX and zLinux customizations.

Even a simple connection to a zLinux environment can be hard for the first time. This system is not as user-friendly as many IT professional are used to deal with on their daily activities. The Enter command is, in this case, triggered through the Right Ctrl key; sometimes, it is hard to get used to this kind of usage, but, yes, people with mainframe and zOs experience would not mix those key commands.

Another example, you can be required to use those system's native tools to simply make a locale change or a system update. Since they are used to work with those tools on their day to day activities, most of those experts can help you find the appropriate tool to use in each specific case.

Links for more information:

Curiosity Rover

http://en.wikipedia.org/wiki/Curiosity_rover

AIX Best Practices for DB2

http://www.redbooks.ibm.com/redbooks/pdfs/sg247821.pdf