This blog entry describes a best practice for how to refresh the database content of an SAP Quality or Development System based on an IBM FlashCopy of an SAP Production System.
The blog entry
Homogeneous System Copy or Refresh Database Content on IBM i with SWPM using an Existing SAP Databas... introduced a new SWPM option to do an
SAP system copy or an
SAP Refresh Database Content using an already existing database library rather than using an export or a saved library. This new SWPM option named
Homogeneous System Copy, Use Existing DB Library gives you the chance to leverage your IBM FlashCopy. Using a FlashCopy has the advantage of creating a 1 to 1 copy of the SAP database library without disturbing or interrupting the source SAP system. In many cases the SAP source system of your FlashCopy is your production system running on a 7x24 basis.
Keep in mind, the SAP System Copy option
Use Existing DB Library is different from using an SAP export directory or a save file of the SAP DB library. As the “new” library exists as soon as the FlashCopy is made, the SWPM can simply use this database library, rename it if necessary, then give it the correct permissions and ownership. Since we are using the flashed ASP as it is, the SWPM can just use it once to make the library part of the target SAP system. When you want to refresh the database content again, take a new FlashCopy and repeat the SWPM operation to use it as an existing DB library. In contrast, when the SWPM was used to perform Homogeneous System Copy operations in the past, working with a save file(savf)or a DB export, the SWPM could use the same source export file or savf repeatedly to either the same or different target systems.
Since most quality and development system databases are refreshed from the production system at some frequency, the topology of the SAP source system and the SAP target system should be adjusted to simplify the process. As you need only the SAP database library for the
SAP Refresh Database Content, you should only install the database library and the database journal receiver library into the IASP.
When you want to use FlashCopy on that IASP for
Refresh Database Content purposes, the SAP filesystem should stay in the *SYSBAS on both the source and the target systems to avoid unnecessary work.
Today, it may be the case that your production SAP filesystem is on an IASP, but this has some big disadvantages if you are trying to use
Refresh Database Content. When the SAP filesystem of the SAP production system is located on the source FlashCopy IASP, you must delete the SAP filesystem on the target FlashCopy IASP during the refresh process. This can take a lot of time related to the number of files and your hardware. For more information about the deleting process, see
SAP Note 2805638, option 1. And when the SAP filesystem of the SAP target system is located on the target FlashCopy IASP, all SAP files of the SAP target filesystem like the profiles, the kernel, etc. are wiped out by the FlashCopy. To get these necessary SAP files of your target filesystem back as they should be, you always need a good and recent backup.
The following diagrams visualize the situation:
The diagram above is an example for an SAP system topology for an SAP Refresh Database Content using a FlashCopy where the SAP filesystem is in the IASP. The SAP filesystem of the PRD system must be deleted after the FlashCopy, and the SAP filesystem of the DEV system is erased by the FlashCopy and must be restored from a backup. This configuration is possible, but the diagram demonstrates why it is not a good idea to locate the SAP filesystem on an IASP of the FlashCopy. If this is how your systems are configured today, know that is not very difficult to move the SAP filesystem from an IASP to the *SYSBAS, see SAP Note 3369420.
This diagram shows an example of a good SAP system topology for an SAP Refresh Database Content using the IBM FlashCopy. After a FlashCopy, no copy of PRD filesystem must be deleted on the target IASP and, additionally, the DEV filesystem is kept untouched on the target host. Now you can continue to perform an SAP Refresh Database Content as describes in the SAP on IBM i blog entry Homogeneous System Copy or Refresh Database Content on IBM i with SWPM using an Existing SAP Databas.... To prepare the target IASP after a successfully finished FlashCopy, use option 2 of SAP Note 2805638.
Note: For an SAP Java System or an SAP Dual-Stack System based on NW 7.0x the feature "Homogeneous System Copy, Use Existing DB Library" is not supported. The dedicated 70SWPM introduced by the SAP Note 2595196 is too old to include this system copy feature already. Instead of using the SWPM option "Homogeneous System Copy, Use Existing DB Library" your only options are to use an SAP Export or an IBM i save file of the source SAP database library. The IBM FlashCopy would not give any benefit here.
For now, good luck with your next SAP Refresh Database Content based on the IBM FlashCopy.
Final Hint: If you plan to create a new SAP system with the SAP database library located on an IASP and with the SAP filesystem located on the *SYSBAS, do the following within the SWPM installation or system copy dialog phase:
When prompted for the destination ASP of the SAP filesystem, choose
1: System ASP.
When prompted for the ASP of the SAP database library, enter the ASP number of your IASP (for example: 33). When you are using the SWPM option Homogeneous System Copy, Use Existing DB Library, enter the ASP number of that (I)ASP where the already existing SAP DB Library is located.