Best practices in migrating SAP applications to Azure – part 2

Опубликовано 25 апреля, 2019

Principal Program Manager, Microsoft Azure Global SAP Deployment Engineering

This is the second blog in a three-part blog post series on best practices in migrating SAP to Azure.

Journey to SAP S/4HANA from SAP Business Suite

A common scenario where SAP customers can experience the speed and agility of the Azure platform is the ability to migrate from a SAP Business Suite running on-premises to SAP S/4HANA in the cloud. This scenario is a two-step process. The first step being migration from enterprise resource planning (ERP) on-premises to the Suite on HANA in Azure, and then converting from Suite on HANA to S/4HANA.

Diagram of the journey to SAP on Azure

Using the cloud as the destination for such a migration project has the potential to save organizations millions of dollars in upfront cost for infrastructure equipment, and can shave roughly around 12 to 16 weeks off the project schedule as the most complex components of the infrastructure are already in place and can easily be provisioned when required. You can see where these time savings come from by looking at the time it takes to go through the request for proposal (RFP) process, to procure expensive servers with large memories, or potentially to procure dedicated appliances with only a five year lifespans such as storage arrays, network switches, backup appliances, and other data center enhancements. Not to mention the time and cost associated with an expertly trained team that can deploy S4/HANA based on tailored data center integration (TDI) standards as required by SAP. These are the same obstacles the consulting firm Alegri was running into during their experience migrating to S/4HANA on Azure. To read more about their experience, refer to Alegri's customer story, “Modern corporate management without any burden.”

While planning for a migration, you want to have a solid project plan that has all the tasks, milestones, dependencies, and stakeholders identified. You will also want a defined governance model and a RACI chart showing which group owns which tasks. Projects of this size have so many moving parts and dependencies between multiple internal and external teams. Disciple in governance is a must.

When getting started with the actual execution, you would typically want to identify all the SAP prerequisites specific to the versions that are currently in use. Larger SAP migration projects will typically have a number of parallel efforts going on at the same time. You want to be sure the infrastructure design on Azure is fully compliant with SAP’s support matrix. To do so, start by reviewing the SAP documentation and deployment guides on AzureAzure's SAP deployment checklist, and the product availability matrix (PAM). This is a great starting point because while you’re working on the initial landscape design, the basis admins can start running the readiness check looking at impact of the legacy custom code in the SAP Business Suite system, the S/4HANA sizing, and other S/4 perquisites required before the upgrade can begin. Together you’ll group on any new items that were uncovered before finalizing the design.

Next is the infrastructure deployment on Azure. The initial deployment is minimal, just enough infrastructure to support the initial sandbox and development tiers. Requirements at this state include:

The above requirements will comprise the new target environment. It is important to note that an ExpressRoute will be required to provide enough bandwidth for migrating medium to large databases. The basis admins can start installing the Suite on HANA database and the initial application servers. This will give the broader project team all the working area they need to run through as many migration runs as necessary to iron out any issues.

We get a lot of questions around the best migration method to use when migrating SAP from on-premises to Azure, which is understandable given the number of options including backup/restore, export/import, SUM and DMO, and more. When migrating the SAP Business Suite to S/4HANA on Azure, it’s easier to use the SUM and DMO option from SAP to handle the database migration and installing new application servers in Azure. This also provides an opportunity to have the new landscape in Azure on the latest supported operating system versions for optimal capabilities, performance, and support. My fellow Azure colleague Kiran Musunuru just recently authored a white paper on “Migration Methodologies for SAP on Azure” that outlines using the SUM and DMO option to migrate SAP Business Suite to S/4HANA as well as tools, options, individual steps, and the overall process of the migration.

Here are some tips that I’ve learned through my migration experience to help you avoid any last minute surprises.

  • Check the minimum required SAP versions and release levels across the landscape.
  • Check the PAM for Java components to see if they are required for your S/4HANA deployment.
  • Use the benchmark tool in DMO to get realistic migration times for the system. This helps with determining the best ExpressRoute sizing for the migration, and sets expectations for required downtimes.
  • Know the Unicode requirement to upgrade to S/4HANA.
  • Know the dual stack systems remediation.
  • Know that OS flavor and versions might differ from existing internal IT standards.
  • Plan for the Fiori deployment.
  • Be prepared to perform multiple migration mock runs for complex or very large landscapes.

Once the migration from the on-premises system to the Azure environment is complete, the conversion from the SAP Business Suite on HANA to S/4HANA can begin. Before starting I would review SAP’s conversion guide for the S/4HANA version that you will be upgrading to. For example, here is the conversion guide for S/4HANA 1809.

Deploying a new S/4HANA landscape can all be done in Azure by the basis team and eliminates any dependencies on the many internal IT teams that would be required with a deployment in a traditional on-premises environment. Most customers will likely start with a simple sandbox or new development system from a system copy of the newly migrated suite on the HANA system. This provides a staging area to run through all the simplification checks, custom code migrations, and actual S/4 conversion mock runs. In parallel, the basis team can start deploying the QAS and production tiers including the new VM’s and configuration for Fiori. Once the necessary checks and conversion have been completed, the process is simply repeated for QAS and production.

This blog post is meant as a general overview of the process and I didn’t touch on any of the functional areas as I wanted to focus on the items that are connected to the Azure platform. We also have a number of scripting and automation options around deploying S/4HANA landscapes on Azure. For an overview you can visit the blog post, “Automating SAP deployments in Microsoft Azure using Terraform and Ansible” written by Tobias Niekamp from the Azure Compute engineering team.

Next week, my colleague Troy Shane will cover the migration of SAP BW/4HANA. It will also cover how best to deploy SAP BW/4HANA in a scale-out architecture today and in the near future when our new Azure NetApp Files becomes generally available for SAP HANA workloads.