Confused by SAP Kernel releases? Read this for your clarification.
The SAP Kernel is the technical core which contains the executable files. It is responsible for communication and execution of SAP programs, like solving the client requests and communicating with the Database and other systems. The Kernel consist of a lot of libraries, drivers and executable files and it is located physically in the file system.
How to classify a SAP kernel
Mostly when SAP releases a new SAP product version, then a new SAP Kernel version is also built and compiled. There are several reasons for this. Firstly, they have fixed earlier SAP Kernel version issues and it supports new operating systems, databases and hardware. These changes to SAP Kernel ensure better reliability and compatibility.
The evolution of the SAP kernel, the introduction date and End of Maintenace date is shown below:
Looking at the graphic it is evident, that the SAP Kernel has a strong dependency to the SAP product and SP level. After SAP NW 7.40 SP08, the SAP Kernel version has been stable. Changing the SAP SP level doesn’t require changing the SAP Kernel version anymore. It is enough only to update SAP Kernel SP level.
What is the different between kernel update and upgrade
SAP recommends keeping an up to date SAP Kernel version. This avoids unplanned SAP systems crash and keeps away issues.
A SAP Kernel package is released to Operation system and database separately. For example, when planning to update SAP Kernel SP level or version, one needs to choose the right operation system version and architecture as well as database and download two SAP Kernel packages. SAPEXE….SAR (an operation system compatibility) and SAPEXEDB….SAR (database compatibility).
But when a new SAP product with new SAP Kernel version has been released, the new Kernel version can also be used with an earlier SAP product, because the SAP Kernel has downward compatibility (DCK). It means that a newest SAP Kernel version can be used with an earlier SAP product, which uses an older SAP Kernel version. This procedure is called the SAP Kernel upgrade: A SAP Kernel version and not the SP level has been changed.
When to update and when to upgrade SAP Kernel
Since SAP releases new SP levels periodically it is recommended to update to a newer SP level occasionally. Keep in mind, that updating a Kernel means, implementing corrections in the Kernel and nobody wants to have too much errors, issues and security defects in the own system.
But sometimes it isn’t possible to update SAP Kernel SP level, because the SAP Kernel version is out of maintenance. Then it is only possible to upgrade the SAP Kernel version. All SAP Kernel versions can be upgraded, even the ones undergoing maintenance.
Upgrading to a newer Kernel version is similar to updating to the latest SAP Kernel SP level. The only difference, but a really important one, is in the Kernel compilation procedure. The SAP Kernel upgrade uses additional database resources, because the new SAP Kernel version stores the new ABAP repository object to the database. After upgrading SAP Kernel it is best to execute SGEN program.
In the diagram below shows, which Kernel goes along with the different SAP NetWeaver versions:
When upgrading SAP Kernel, follow these SAP recommendation notes:
- 2251972 – Using kernel 7.45 instead of kernel 7.40, 7.41, or 7.42
- 2350788 – Using kernel 7.49 instead of kernel 7.40, 7.41, 7.42 or 7.45
- 2556153 – Using kernel 7.53 instead of kernel 7.40, 7.41, 7.42, 7.45, or 7.49
All these Kernel versions support HANA database.
You can display the NetWeaver version:
Open menu “System” -> “Status …” -> click the Component button
You can display more info about the Kernel:
Open menu “System” -> “Status …” -> click the “Other kernel info.” Button