The AIX Operating System

What is AIX? 

AIX 5L is an open UNIX operating environment from IBM. It provides high levels of integration, flexibility and reliability—essential for meeting the high demands of today's e-business applications. It operates over IBM pSeries, IBM Cluster 1600 and IBM RS/6000 servers and workstations.

AIX is fully integrated to support the concurrent operation of 32- and 64-bit applications in their full range of scalability, with key internet technologies such as Java and XML parser for Java included as part of the base operating system. Best of all, a strong affinity between AIX and Linux permits popular applications developed on Linux to run on AIX with a simple recompilation.

What does that mean??? 

AIX was developed by combining the BSD and System V versions of UNIX.  Most of the difference between AIX and other UNIX operating systems can be found in the way the OS is managed, most noticeably with the System Management Interface Tool, or SMIT.

AIX will run in either 32- or 64-bit mode.  It will not run 32- and 64-bit applications at the same time.

IBM offers several different types of hardware platforms, including the pSeries, which  is what runs the AIX operating system.

The RS/6000

The Reduced Instruction Set Computing System 6000 is a hardware platform that supports the AIX operating system.

RISC has been in existences since the 1970s, when it was developed by IBM.  The basic premise was to reduce the number of instructions needed to carry out a given task, which in turn reduces processor time.

The operating system is responsible for resource allocation, including CPUs, memory, processes, and devices.  The operating system will manage these resources based on factors such as schedule, priority, ownership, and access privileges.  It is comprised of three layers:

·         Command layer (shell)

·         Service layer

·         Kernel (manages resources)

Figure 1.1 displays the hierarchy of how responsibilities are divided up in an operating system.

Installing AIX

There are several options when installing the AIX base operating system (BOS).

·         New and Complete Overwrite - This method installs AIX on a new machine or completely overwrites any BOS that exists on your system.

·         Preservation - This method replaces an earlier version of the BOS but retains the root volume group, the user-created logical volumes, and the /home file system. It overwrites the /usr, var, tmp, and / (root) file systems. Product (application) files and configuration data are lost.

·         Migration (POWER-based systems only) - This method upgrades from an older version of AIX.  A migration installation preserves most file systems, including the root volume group, logical volumes, and system configuration files. It overwrites the /tmp file system.

When installing AIX, the easiest method is to use the SMIT menu, which will be covered in a later section.

Any AIX operating system software can be installed in two different states:

·  Applied: The software has been installed, but the previous version has been retained. The new version can be uninstalled without needing additional files.

·  Committed: The software has been installed, and the previous version has been destroyed.  If the new version must be uninstalled, it will need to be downloaded or installed from installation media.

And there are different types of files that can be installed. Between the most common we can find

RPM (RedHat Packages previously compiled for AIX) you can find them at ftp.software.ibm.com

installp packages that is the AIX package standard

and source code packages that can be compiled directly in the system.