SAP Cloud Computing has landed. Did you know that the SAP Cloud Enabler LVM is historically derived from the Adaptive Computing Controller (ACC for short), which was first implemented at the turn of the century under SUSE Linux? It is sometimes worth looking back to sharpen the view forwards.
Virtualization on a SAN and NAS basis, which preceded Intel virtualization in the SAP Enterprise environment, was considered the innovation at the turn of the century. Intel server virtualization was then still in its infancy; blade server infrastructures – with their low hardware footprint – were all the rage at that time. A real server virtualization was not a real milestone at the time.
Attention was focused on the ability to decouple SAP services from the OS. Storage virtualization, in particular, enabled this development. It was almost a point of focus to keep all information in a central location. SAP services were therefore able to access the servers on an equal footing. The aim of the concept: the central storage of necessary local changes made to the OS, such as LDAP or mount logic. Everything an SAP application needs was stored at a central point, and was therefore decoupled from the actual OS. The effect was a movable workload on each server, integrated in an SAP infrastructure, combined with the advantage of a simplification and reduction in workload of: SAP system exchange, OS updates, hardware maintenance, creation of system copies, or system cloning.
Logical rather than
Intel virtualization provided the physical servers on VMware with a further degree of freedom. This added additional capabilities such as live migration to the approach of SAP Adaptive Computing – in some ways, a precursor of SAP Cloud Computing. Formerly, it was necessary to shut down SAP services in order to perform hardware maintenance. It is therefore clear that the resources gained resulted from the added value of the Intel VMware virtualization. This is because the system was no longer dependent on physical units, but now on logical units.
In today’s world, virtualization with VMware has intrinsically become developed into systems as a matter of course. Suse and VMware were incorporated internally at SAP to drive forward hardware virtualization, including against the background of SAP Cloud Computing with various Cloud Computing versions such as SAP Private Cloud.
Why specifically the integration of Linux? Thematically, we must see that it is immensely important to be able to decouple the SAP application logic from the OS, or to use the operating system as standard functionality. In Unix/Linux, this is installed at the outset. To keep in step with requirements was, and is, a relatively easy undertaking with the use of Linux. This also applies to the implementation, particularly in view of the tasks: initial deployment, maintaining the flexibility or minimizing patching.
High availability –
You could say: The concept of LVM and Linux fit together in an ideal manner; if you will, a perfect tandem. By contrast, in Windows, the approach is based more on local retention of resources, because here the desktop originally formed the center of the thinking. In concrete terms, for example, the registry applications are retained locally – with the consequence that in the conception, implementation, operation and maintenance, massive expenses are sometimes required to get to the goodies that Linux, as it were, already has in its belly.
And in order to ensure a corresponding high availability, for example, in the SAP Private Cloud, the SAP Linux lab developed the reference architecture of the shared lib. The focus here: an HA cluster integration in SAP LVM. SUSE has also played a key role in the HA extension. Customers can rely on a cluster solution that follows the reference architecture specified by SAP – and in addition, that has SAP LVM integration, and is also supported via the SAP Solution Manager.
Conclusion: For more than ten years, SUSE Linux has provided active support for the ACC, the LVM, and thereby Cloud Computing of today and tomorrow. As a result, this makes SAP Cloud Computing easy for existing SAP customers on Linux.