Now that SAP have pushed back the End-Of-Life for SAP Business Suite 7, a number of options open up for companies to take advantage of SAP technology, in the middle ground that exists between standard SAP ERP 6.0 and SAP S/4HANA.
Namely, the Suite on HANA (SoH) option, of running SAP ERP 6.0 on the SAP HANA database.
In this article we show you how to approach the task of sizing a Virtual Machine for Suite-on-HANA in Microsoft Azure.
(For more details on the EoL change see: SAP Business Suite 7 To Go To 2027)

 

What is Suite-on-HANA (SoH)?

SAP ERP 6.0 is just one software component in a group of related components that make up the SAP Business Suite product offering.
Suite-on-HANA as a supported technology stack has been around since 2012 for SAP ERP 6.0 EHP 6 and SAP HANA 1.0.
Simply put, the HANA database is used as the system database for an ERP 6.0 system.
This is instead of what is more commonly known as “AnyDB” in the SAP documentation. “AnyDB” is referring to any database other than SAP HANA.

The ERP 6.0 EHP6 Suite on HANA maintenance ends on 31st December this year (2020), so it is recommended to use later versions of those software stacks, for example: ERP 6.0 EHP 8 and SAP HANA 2.0.

 

Can We Technically Move to SoH In Our Specific Case?

First, we need to check the restrictions for SAP Business Suite using SAP note 1774566 – “SAP Business Suite – Restrictions”.
There are a few restrictions in the list that would mean we are not able to move to SoH, especially for things that might need multiple HANA database server virtual machines under one HANA database (a.k.a HANA scale-out).
If you have scale-out concerns, then take a look at SAP note 1825774 – “SAP Business Suite Powered by SAP HANA – Multi-Node Support”.
In our example scenario, we are using ERP 6.0 and we do not need to consider scale-out, so we don’t appear to be restricted, according to that SAP note.

Where Can You Host a HANA System?

Due to the hardware requirements for the HANA database, there are only really 3 hosting choices that a company has:

  • On-Premise (buying or leasing the hardware) – could also be known as Private Cloud, but not a lot of companies have real IaaS internally.

  • Managed Service Provider/Partner hosts it for you. This could also be as IaaS.

  • Public Cloud (IaaS).

  • In this scenario we are going to see how we can size for Public Cloud, in particular for Microsoft Azure public cloud, although the steps will be extremely similar for any Public Cloud provider.

 

Sizing for SAP HANA in Azure

It’s not a simple task to size anything in Azure, add into this the HANA database’s specific certification requirements and you’re into an Excel analyst’s idea of heaven (do you love spreadsheets?).
In this example, we’re going to ignore the need for a business case. I know, I know, it’s one of those things where you will actually need one, because otherwise how will you be able to measure success, in business terms?
Let’s imagine that the business case is already sold to the executives on the HANA credentials in some way or another.

 

How Do We Size Our HANA Database?

There are two methods of sizing the HANA database for Suite-on-HANA, depending on your current situation:

1, New SoH Install (no prior ERP on AnyDB).
You plan to install a new SoH system (i.e. you have no current ERP system), then you may need to take the output of the Quicksizer SAPS calculation and look at what HANA certified hardware is applicable.
In this particular case you would need a good argument for not installing SAP S/4HANA instead, it’s the newer product and will more than likely cover your requirements.

                 

This option is for a new install of Suite-on-HANA. You will need an idea of business transactional throughput and data volumes, data retention periods and any plans to perform data volume management tasks (cleanup) to be able to complete the Quicksizer, which will allow you to size the potential business system.
You can reference the following:
SAP note 85524 – “Sizing SAP Business Solutions (e.g. with the Quicksizer)” for some guidance.
You can find more about the Quicksizer here: https://www.sap.com/docs/download/2016/10/34995878-8f7c-0010-82c7-eda71af511fa.pdf
There are two main types of Quicksizer:
Classic Version (on AnyDB): https://apps.support.sap.com/sap/bc/bsp/sap/qs_oberflaeche/main.do?bsp-language=en
HANA version: https://apps.support.sap.com/sap/bc/bsp/sap/qs_oberflaeche/hana.do?bsp-language=en

You will find that the “HANA” version of the Quicksizer includes a section for “SAP Business Suite powered by HANA” but that SAP ERP is not listed in that section!
Therefore, a brand new install of ERP on HANA is quite possibly not the best direction and SAP themselves are encouraging you to use S/4HANA.

NOTE: the SAP Quicksizer uses the following classifications of sizes of systems based on the SAPS number:
SAPS Category:
XS <= 8000
S <= 16,000
M <= 32,000
L <= 48,000
XL <= 72,000
XXL > 72,000

2, DB migration of existing ERP on AnyDB.
You are moving from an existing installation of SAP Business Suite on “anyDB” (non-HANA) to Suite on HANA, then you can execute an ABAP sizing report program in your existing SAP system.

We can use SAP note 1872170 – “ABAP on HANA sizing report (S/4HANA, Suite on HANA…)” to execute the required report.
It’s possible that you will need to load the latest report ABAP code into your target production SAP system (it should be transported through your landscape) and you may even need to apply some ST-PI updates via SPAM.
If you don’t want to run it in production, then provided you run it on a system that is a (recent) copy of production, then this is fine. It does not need to be the same hardware as production, because the report is looking at data volumes inside the database.

Remember, this is sizing the database only, it will not account for any application server increase if you are also planning on adding more users to your target Suite-on-HANA system.

The output will be an estimated memory sizing requirement for the HANA database.
The sizing report memory recommendation does *not* translate directly to the hardware size on the HANA hardware certification list because it excludes:

  • O/S memory requirements.
  • HANA XSA (application server) if you are using
  • Memory for additional software such as HIPS, A/V, or if running the ABAP stack on the same server (non-production).

Make sure you allow for these additional memory requirements when choosing a VM size in Azure.

Remember there is a direct relationship between memory and CPU in a computing environment.
This is because there are defined limits to the amount of memory that an individual CPU can address. This limit differs by processor vendor and generation (age).

Source: https://www.anandtech.com/show/14146/intel-xeon-scalable-cascade-lake-deep-dive-now-with-optane

For this reason, we see a large range of Virtual Machines to choose from, but they do not come in small incremental sizes of just one or two extra vCPUs.

 

Checking Supported Azure VM Types for HANA

We are going to assume that we have executed the Sizing Report (based on the SAP note 1872170) in an existing ERP on AnyDB system.
Let’s imagine that our sizing report came out with a requirement for the HANA database to have 128GB of RAM. This equates to about 30,000 SAPS, if we assume the CPU to Memory ratio is 4GB per CPU core.

We start by checking SAP note “1928533 – SAP Applications on Azure: Supported Products and Azure VM types”.
This is specific to our choice of Public Cloud vendor (Azure).

What is needed for a HANA database requirement of 128GB ~ 30,000 SAPS (as at May 2020):

VM Series     VM Type             CPU & RAM      SAPS (2-tier)
Esv3-series   Standard_E16s_v3    16vCPU 128GB   17,420
Easv4-series  Standard_E16as_v4   16vCPU 128GB   24,175
Dsv3-series   Standard_D32s_v3    32vCPU 128GB   34,840
Dasv4-series  Standard_D32as_v4   32vCPU 128GB   48,350
DSv2-series   Standard_DS15_v2    20vCPU 140GB   30,430
Esv3-series   Standard_E20s_v3    20vCPU 160GB   21,775
Easv4-series  Standard_E20as_v4   20vCPU 160GB   30,219
M-series      Standard_M32ts      32vCPU 192GB   33,670
Dsv3-series   Standard_D48s_v3    48vCPU 192GB   52,224
Dasv4-series  Standard_D48as_v4   48vCPU 192GB   72,525

The list above is just an extract, but we can see we have a number of VMs within our region of our proposed requirement of 128GB of memory.
NOTE: We need to remember, that we are looking for a VM with more than 128GB of RAM, to allow for HANA, O/S and other software.

We now need to check the HANA IaaS certification list, and we look for our specific Public Cloud vendor’s offerings.
Following the URL will show you the Azure VMs on which HANA is certified:

https://www.sap.com/dmc/exp/2014-09-02-hana-hardware/enEN/iaas.html#categories=Microsoft%20Azure%23OLAP%23OLTP%23HANA-IAAS%201.1%23HANA-IAAS%201.0%23HANA-IAAS%202.0&order=Vendor

Comparing what is certified (in general) with what is certified for HANA, we can see the following (as at Apr 2020):

VM Type          VMSize   Mem   2-Tier SAPS
Standard_M32ts   32vCPU   192   33,670
Standard_M32ls   32vCPU   256   33,670
Standard_E64s_v3 64vCPU   432   70,050
Standard_GS5     32vCPU   448   41,670
Standard_M64ls   64vCPU   512   66,600
Standard_M64s    64vCPU   1024  67,315
Standard_M64ms   64vCPU   1792  68,930
Standard_M128s   128vCPU  2048  134,630
Standard_M128ms  128vCPU  3892  134,630

Let’s now look at the Azure pricing calculator for those applicable VMs in the UK South region (they may not be available in your preferred region!):
(https://azure.microsoft.com/en-gb/pricing/calculator/)

Standard_M32ts        £1,946.16 per month.
Standard_M32ls        £2,051.71 per month.
Standard_E64s_v3   £2,543.01 per month.
Standard_GS5          £4,046.29 per month.

All the above mentioned costs are for Pay-As-You-Go.
There are other pricing options, which could save you up-to 70% of the cost of the VM, but you will be committing to that cost for up-to 3 years.
See the post SAP on Azure Hosting Costs for a comparison of cost savings with Reserved Instances.

We can see that we have a number of options around the M-series VMs, which will give added benefits to HANA such as Azure WriteAccelerator.
(You can find more information on WriteAccelerator here: https://azure.microsoft.com/en-us/blog/write-accelerator-for-m-series-virtual-machines-now-generally-available/)

These M-series VMs fit nicely with our 128GB requirement for HANA, plus leaving memory free for the O/S and other software.
The other VMs on the list are too highly specified with regards to memory. We do not require 432GB or above, it would be wasted.

We also need to bear in mind that our sizing report is an estimate. What if we actually need less capacity than the report suggests?
In the original SAP Quicksizer information, SAP state that you should be capable of sizing both upwards and downwards once you have established what the real load requirements are (after running the system).
If we had to downsize the VM, we cannot. We are stuck at the M32ts because while the Standard_DS14_v2 (not shown above) is on the SAP HANA certification list, it’s only for SAP Business One and not for Suite-on-HANA.

 

What about non-Production?

We could probably estimate that we are more than likely going to need smaller VMs for the non-production SAP systems.
This is where SAP note 2271345 – “Cost-Optimized SAP HANA Hardware for Non-Production Usage” comes into play.
The note states that Production HANA systems are only supported on Intel on high-end E7 or high-end E5 processors. (It does not mention AMD processors, but the note has not been updated since 2018).
Of more importance is the statement that for non-production servers *any* (high-end or low-end) E7 or E5 processors can be used. Since the VMs with these CPUs will not be listed in the HANA certified list, it means we can ignore the list and just chose a VM from the Azure catalogue.
It also states that the memory to CPU core ratio doesn’t need to be followed in non-production systems.

All of the above means that for non-production HANA VMs in Azure, we have the option to use something like a “Standard_DS15_v2” with 20vCPU and 140GB RAM at just £1,497.84 per month in UK South region.
There is no requirement for the M-series in non-production.

 

Summary

Instead of summarising the path we have taken with words, I’ve tried to make it into an info-graphic.


 


References:

1774566 – SAP Business Suite – Restrictions
1825774 – SAP Business Suite Powered by SAP HANA – Multi-Node Support
85524 – Sizing SAP Business Solutions (e.g. with the Quick Sizer)
1723135 – Resource requirements for SAP ERP Central Component 6.0 EHP6
1872170 – ABAP on HANA sizing report (S/4HANA, Suite on HANA…)
2271345 – Cost-Optimized SAP HANA Hardware for Non-Production Usage
1501701 – Single Computing Unit Performance and Sizing
2271345 – Cost-Optimized SAP HANA Hardware for Non-Production Usage

SAP ERP Sizing Guidelines
https://help.sap.com/http.svc/login?url=/viewer/p/SAP_ERP_SIZING

What is SAP QuickSizer:
https://www.sap.com/docs/download/2016/10/34995878-8f7c-0010-82c7-eda71af511fa.pdf

Quicksizer classifications:
https://apps.support.sap.com/sap/bc/bsp/sap/qs_oberflaeche/pdf1.htm?area=QSDOC&filename=res_note.htm

HANA certified hardware list:
https://www.sap.com/dmc/exp/2014-09-02-hana-hardware/enEN/iaas.html#categories=Microsoft%20Azure%23OLAP%23OLTP%23HANA-IAAS%201.1%23HANA-IAAS%201.0%23HANA-IAAS%202.0&order=Vendor

Axure VM Overview:
https://docs.microsoft.com/en-us/azure/virtual-machines/sizes-memory

Azure Pricing Calculator:
https://azure.microsoft.com/en-gb/pricing/calculator/

Azure WriteAccelerator:
https://azure.microsoft.com/en-us/blog/write-accelerator-for-m-series-virtual-machines-now-generally-available/