When you migrate your operating system from AIX Version 4.3 to AIX 5L, you need to verify whether or not your applications will run with the new version of the operating system as before. You need to verify if it is necessary to upgrade the application release at the same time as the operating system migration. In other cases, you may need to only apply patches.
Another issue is moving your application to a different hardware platform as well. This may include transferring your data with external disks by first exporting the data and then importing it onto the new hardware running AIX 5L. One of the most important tasks for you to do is to refer to your applications vendor
documentation. This way, you will find detailed upgrade procedures that will help you migrate your applications safely and with minimized downtime from AIX Version 4.3 to AIX 5L. Most importantly, allow enough time for porting your applications to AIX 5L and consider setting up test environments prior to starting the migration of your production environment. This is going to be the most crucial part of your migration process.
In the next chapters, we concentrate on some of the most used applications at customer sites. We will not describe a detailed upgrade procedure for each application, but we want to give some guidelines of the order of the migration process, things to be aware of and to look out for, and necessary tasks to do to prepare your system.
8.1 SAP and Oracle
In this section, we will not describe a detailed upgrade of SAP or Oracle, but concentrate on the AIX related issues involved when migrating your AIX Version 4.3 system running Oracle 8.1.7 to AIX 5L Version 5.1 running Oracle 9.2. The information we provide is complementary to the documentation of the official SAP Guide Upgrade to Oracle Version 9.2.0: UNIX. Furthermore, we will not cover every issue involved for each customer situation. This information acts as a guideline of things to consider when planning your migration process. We discuss how and in what order to do the AIX migration and Oracle upgrade and outline post-migration issues. In particular, customers running SAP/Oracle in 64-bit mode need to carefully plan and prepare the migration to AIX 5L. The reason for that is that some necessary operations, such as increasing the system table space, cannot be done after the operating system migration is completed.
Another important issue for most customers is the minimization of the system’s downtime. There are several pre-migration steps you can perform on the original AIX Version 4.3 system in order to keep the downtime low when migrating your operating system to AIX 5L and your database to Oracle 9.2. We will discuss certain issues involved in moving hardware platforms. This involves moving from a POWER3 machine running AIX Version 4.3 to a POWER4 machine, like IBM
^ pSeries p630, p650, p655, p670, or p690 running AIX 5L as well as SAP and Oracle.
Another good source of information related to SAP and AIX is the following publication, A Holistic Approach to a Reliable Infrastructure for SAP R/3 on AIX, SG24-5050. This includes AIX shared memory management and other
performance related issues.
At the time of the writing of this redbook, the 64-bit product availability for AIX, DB2 UDB, and Oracle DB is as shown in Table 8-1 on page 181. SAP has certified AIX 5L Version 5.1 and 5.2 of the AIX 5L family. For further information, refer to SAP Note 502532. For information on how to access SAP Notes, refer to 8.1.1, “Pre-migration issues” on page 181. Detailed information about which SAP component is available for each of the database and Web Application Server versions can be obtained from the infoservice at the IBM SAP International Competence Center (ISICC). You need to contact [email protected].
Chapter 8. Applications 181
Table 8-1 SAP DB and APP server on pSeries 64-bit availability
8.1.1 Pre-migration issues
Before you start planning and preparing the migration process, read this section carefully and refer to the SAP notes. These can be found at the SAP Service Marketplace at the following Web sites:
http://service.sap.com/instguides http://service.sap.com/notes
http://service.sap.com/systemmanagement
To access the Web sites of SAP Service Marketplace, you need an SAPNet user ID (which can be obtained at http://service.sap.com). Some of the relevant SAP Note numbers are 540 021, 539 921, 539 970, and 539 922. Furthermore, this is the place where you find the official Oracle 9.2.0 Migration guide called
Upgrade to Oracle Version 9.2.0: UNIX.
As with the AIX migration, when you plan and prepare your migration process, ensure that you have all the needed software ordered and available. This includes AIX 5L and appropriate maintenance levels as well as the SAP Update Kits:
OS Update Kit AIX 5L Version 5.1 64-bit 4.6D Kernel
OS Update Kit AIX 5L Version 5.1 64-bit 6.2.0 Kernel
Additionally, you need to download Oracle patches and patch sets, as described in the guide book Upgrade to Oracle Version 9.2.0: UNIX.
32-bit versus 64-bit
It is possible to execute both 32-bit and 64-bit software on the 32-bit as well as on the 64-bit AIX kernel. The advantage of the 32-bit AIX kernel is the ability to deal with existing resources. The 64-bit AIX kernel allows you, however, to
Operating system Database SAP Basis/Web
Application Server AIX Version 4.3 Oracle 8.1.7 4.6D, 6.1, 6.2
DB2 UDB V7 4.6D, 6.1, 6.2 AIX 5L Version 5.1 and 5.2 Oracle 9.2 Oracle 9.2
Oracle RAC 6.2
DB2 UDB V7 4.6D, 6.2
access more than 96 GB of RAM. For further discussions on this topic, refer to 4.2.2, “Binary compatibility” on page 43.
8.1.2 Migration and upgrade procedure
In this section, we describe the steps necessary to migrate your system from AIX Version 4.3 to AIX 5L Version 5.1, as well as outline the Oracle upgrade
procedure when moving your database from Version 8.1.7 to 9.2.0. We begin with some preparation tasks that you should do on your AIX Version 4.3 system prior to the migration process. In the next step, we prepare the SAP kernel, do the Oracle upgrade, and start the AIX migration itself.
AIX prerequisites
The prerequisites for AIX 5L Version 5.1 and Version 5.2 are listed in the following sections.
AIX 5L Version 5.1
For the post-migration, you will need the latest maintenance level of AIX. You can reduce the total downtime of your system if you already download it at this stage. The latest maintenance level for AIX 5L Version 5.1 is (at the time of writing) ML 03 which you can download at the following URL by searching for APAR IY32749:
http://techsupport.services.ibm.com/server/aix.fdc
Additionally, you need to check and see if you have the following APARs installed and download them using the same URL if needed:
IY28949: Array pointer incorrectly used in aio_nwait
IY28766: Add bread/bwrite, lread/lwrite, and phread/pwrite for
IY30150: waitpid dumps core on 64-bit, when called from escepti
IY29965: THREAD_WAIT() computes wait time incorrectly
IY26778: truss does not report the coded Error Numbers
The way to check if they are installed on your system is by using the instfix
command, as shown in Example 8-1 on page 183. The first two lines represent the case where you do not have to install the command because it already is on your machine. The second case demonstrates the output you get when it is not on your system. In this case, you need to download the fix.