How to Install multiple DB2 9 database servers for SAP

Prior to DB2 for Linux, UNIX, and Windows Version 8, SAP customers can install only one copy of each DB2 version on a single physical machine, because the installation path is hard coded. Although DB2 Version 8 provides replacement revision package images, these images are used only for testing, and SAP does not support them in production environments.

For DB2 9, customers can install multiple DB2 software copies on a single physical machine. The database installation is independent of each other. They can be of different levels and can be installed on any valid path. Each copy can be updated independently, without affecting each other. This feature is supported in all environments with the SAP R/3 3.1I version of DB2 9. In addition, starting with SAP NetWeaver 7.1, SAP Installer fully utilizes this feature to install the DB2 software in the home directory of the instance owner.

This article explains how to set up multiple DB2 systems on a single Linux or UNIX machine and have SAP applications run with the different database software installed.

Install multiple DB2 copies on one system

Benefits of coexistence of multiple DB2 9 copies

For DB2 9, customers can install DB2 software multiple times on the host and assign a different DB2 installation to an SAP DB2 instance. Each DB2 software instance that is installed runs independently. In addition, each revision package is provided as a complete installation image, so you can choose whether to install it on a previous image or as a new image.

With this improvement, customers can allow different SAP applications to run on different levels of DB2 on the same host. For example, you can deploy and test your SAP application with a new revision package, and then move your production system to a new installation. It also provides a way to easily return to the previous patch level. Each instance can be updated independently. You do not need to apply a revision pack to a previous version and apply it to all instances, but the old method is still supported.

For example, suppose the customer has instances of I1, I2, and I3. He installs the original version of DB2 9 and updates all instances accordingly. Then install DB2 9 Fix Pack 1, and he can choose to install on the original version that is already installed, or on another path. The instance I1 and I2 are then directed to the new path for updating. Then, install DB2 9 Fix Pack 2 on the new path. At this point, you can also update all instances including I3 to Fix Pack 2 by pointing to the new path.

You can install both version 8 and version 9 on the same physical machine, or you can install multiple levels of revision packs for version 9.

Differences from previous versions of DB2

This new feature has led to many changes in DB2:

You cannot use operating system utilities (such as paged, RPM, Smit, or sisal) to query DB2 products. Instead, use a new command to DB2LS track the DB2 software installed on the machine. It provides information about the installed DB2 products, including the version and time of installation.

Example:

%/opt/ibm/db2/v9.1_01/install/db2ls

Install Path level fixpack Special Install number Install Date

---------------------------------------------------------------

/OPT/IBM/DB2/V9.1_01 9.1.0.0 0 Tue June 14:28:33 2006 EDT

/opt/ibm/db2/v9.1_02 9.1.0.1 1 Thu Sep 7 16:52:14 2006 EDT

The user cannot uninstall the DB2 software using the native operating system utilities (such as ramp or Smit). To uninstall the DB2 product, you should run the Db2_deinstall command, which is located under the installation directory.

Example:

%/opt/ibm/db2/v9.1_01/install/db2_deinstall-a

The above command removes the DB2 product from the/opt/ibm/db2/v9.1_01 directory.

Each DB2 system can have any number of DB2 instances. However, the instance name must be unique throughout the system. Command Db2ilist lists only the instances created under the path where the command was run. Similarly, the Db2ilist db2icrt and Db2idrop commands are used to create and delete instances associated with the DB2 path where the command was run.

DB2 9 Revision Bao Ying is a complete installation image. You can use an image to run a completely new database installation, or you can apply a revision pack to an existing installation. The installation procedure described below applies to the original version of the DB2 9 image and to the revision package image. The only difference is that if a user runs a new installation using a revision pack image, a trial license is installed. Then, you need to run DB2LICM a filename to add the license manually.