SUSE and Microsoft Solution Templates for SAP Applications

Simplified Deployment on Microsoft Azure
SUSE Linux Enterprise Server for SAP Applications

Peter Schinagl, Technical Architect SAP, SUSE

This document describes several predefined solution templates for SAP Applications from SUSE and Microsoft for simplified deployment on Microsoft Azure.

1.0 Overview

For every template there are four possible sizes available with the following naming convention:

  • Demo

  • Small

  • Medium

  • Large

The Demo and Small sizes are targeted at non-production SAP HANA workloads. The Medium and Large sizes can be used for production systems, as they are built on M-SERIES/VM which are certified.

One of the presumptions of this document is that you are familiar with SAP Netweaver and SAP HANA.

Microsoft provides a good overview page about SAP deployments in Azure at https://docs.microsoft.com/en-us/azure/virtual-machines/workloads/sap/get-started

For the High Availablity (HA) scenario you should have in addition good knowledge of

For production systems you need to take care of the monitoring requirements of SAP:

You need to provide the SAP software and license by yourself. You can download SAP software from the SAP Service Marketplace (https://service.sap.com)

To prepare the Azure VM for the SAP Netweaver and HANA installation, follow the steps outlined in the section below.

1.1 Operating System Updates

Check for SUSE Linux Enterprise Server operating system updates and fixes before installing additional software. By installing a patch, you might be able to avoid calling the support desk.

Here is an example of how to check for available patches for SUSE Linux Enterprise Server by using the zypper command:

sudo zypper list-patches

Depending on the kind of issue, patches are classified by category and severity.

Commonly used values for category are: security, recommended, optional, feature, or yast.

Commonly used values for severity are: critical, important, moderate, low, or unspecified.

The zypper command searches only for the updates that your installed packages need. As an example, you could use the command:

sudo zypper patch --category=security,recommended --severity=critical,important

You can add the parameter --dry-run to test the update without actually updating the system.

2.0 SAP HANA 2-tier (DB-tier) Template

The template provides and deploys a VM that is customized for use with SAP HANA, using the latest pay-as-you-go (PAYG) version of the SUSE Linux Enterprise Server for SAP Applications (SLES4SAP).

It deploys one server on Premium Storage (Premium_LRS) and uses Managed Disks.

Figure 1 SAP HANA 2-tier (DB-tier) Template Overview

2.1 OS Configuration for SAP HANA

SAP HANA requires specific Linux kernel settings, which are not part of the standard Azure images and must be set manually.

sudo saptune solution apply HANA

2.2 Disk Overview

The template uses the following disks and mount points for the HANA machine:

Demo

Mount Point

Disk

Size

/hana/data

0,1

128 GB

/hana/log

2,3

128 GB

/hana/shared

4

128 GB

/usr/sap

5

128 GB

/hana/backup

6

128 GB

/sapmnt

7

128 GB

Small

Mount Point

Disk

Size

/hana/data

0,1,2

512 GB

/hana/log

same disks as data

/hana/shared

3

512 GB

/usr/sap

4

64 GB

/hana/backup

5

1024 GB

/sapmnt

6

64 GB

Medium

Mount Point

Disk

Size

/hana/data

0,1,2,3

512 GB

/hana/log

4,5

512 GB

/hana/shared

6

1024 GB

/usr/sap

7

64 GB

/hana/backup

8,9

1024 GB

/sapmnt

10

64 GB

Large

Mount Point

Disk

Size

/hana/data

0,1,2

1024 GB

/hana/log

3,4

512 GB

/hana/shared

5

1024 GB

/usr/sap

6

64 GB

/hana/backup

7,8

2048 GB

/sapmnt

9

64 GB

For the installation of SAP HANA there are different ways available. You can use the native SAP mechanism of using the SAP Software Provisioning Manager (SWPM) or the HANA database lifecycle manager (HDBLCM).

For details, have a look at the SAP documentation at https://help.sap.com/viewer/p/SAP_HANA_PLATFORM.

A very short description is in addition available at https://docs.microsoft.com/en-us/azure/virtual-machines/workloads/sap/hana-get-started .

Another way would be to use the SUSE YaST based HANA install wizard, which simplifies the setup. It is discussed in a later section below.

3.0 SAP Netweaver 3-tier Template

The template provides and deploys several VMs which are customized for use with SAP Netweaver and SAP HANA as database, using the latest pay-as-you-go (PAYG) version of the SUSE Linux Enterprise Server for SAP Applications (SLES4SAP).

It deploys all server on Premium Storage (Premium_LRS) and using Managed Disks.

Figure 2 SAP Netweaver 3-tier Template Overview

3.1 OS Configuration for the SAP Netweaver VM

SAP Netweaver requires specific Linux kernel settings, which are not part of the standard Azure images and must be set manually.

sudo saptune solution apply NETWEAVER

3.2 OS Configuration for the SAP HANA VM

SAP HANA requires specific Linux kernel settings, which are not part of the standard Azure images and must be set manually.

sudo saptune solution apply HANA

For more details see the documentation at https://www.suse.com/documentation/sles-for-sap-12/book_s4s/data/sec_saptune.html

3.3 Disk Overview

The template uses the following disks and mount points for the HANA machine:

Demo

Mount Point

Disk

Size

/hana/data

0,1

128 GB

/hana/log

2,3

128 GB

/hana/shared

4

128 GB

/usr/sap

5

128 GB

/hana/backup

6

128 GB

/sapmnt

7

128 GB

The XSCS machine uses only the base OS disk.

The APP server machines use an additional 128 GB disk for /usr/sap/<SID>.

Small

Mount Point

Disk

Size

/hana/data

0,1,2

512 GB

/hana/log

same disks as data

/hana/shared

3

512 GB

/usr/sap

4

64 GB

/hana/backup

5

1024 GB

The XSCS machine uses only the base OS disk.

The APP server machines use an additional 128 GB disk for /usr/sap/<SID>

Medium

Mount Point

Disk

Size

/hana/data

0,1,2,3

512 GB

/hana/log

4,5

512 GB

/hana/shared

6

1024 GB

/usr/sap

7

64 GB

/hana/backup

8,9

1024 GB

Large

Mount Point

Disk

Size

/hana/data

0,1,2

1024 GB

/hana/log

3,4

512 GB

/hana/shared

5

1024 GB

/usr/sap

6

64 GB

/hana/backup

7,8

2048 GB

3.4 Other Settings and Machines

All machines created with the template use the Azure feature Accelerated Network (AN) (only if the VM size supports AN).

The XSCS machine gets a dynamic public IP address to be able to access all other machines in the private network and only uses the base OS disk. There is no additional disk.

The APP server machines use an additional 128 GB disk for /usr/sap/<SID> and the machines are placed in an Availablity Set with a FaultDomainCount of 2 and an UpdateDomainCount of 20.

NOTE: Availability Set

An Availability Set is a logical group in Azure to ensure that the VM resources are isolated from each other when they are deployed within an Azure datacenter. It ensures that the VMs you place within such an Availability Set run across multiple physical servers, compute racks, storage units and network switches. The Virtual Machines are placed then into an Availability Set to minimize the chances that two of them fail or are updated at the same time. This is essential when you want to build reliable cloud solutions and clusters.

4.0 SAP Netweaver 3-tier HA Template

The template provides and deploys several VMs twice to be used in an HA configuration. They are customized for use with SAP Netweaver and SAP HANA as database, using the latest pay-as-you-go (PAYG) version of the SUSE Linux Enterprise Server for SAP Applications (SLES4SAP).

It deploys all servers on Premium Storage (Premium_LRS) and using Managed Disks.

Figure 3 SAP Netweaver 3-tier HA Template Overview

4.1 OS Configuration for the SAP Netweaver VM

SAP Netweaver requires specific Linux kernel settings, which are not part of the standard Azure images and must be set manually.

sudo saptune solution apply NETWEAVER

4.2 OS Configuration for the SAP HANA VM

SAP HANA requires specific Linux kernel settings, which are not part of the standard Azure images and must be set manually.

sudo saptune solution apply HANA

For more details see the documentation at https://www.suse.com/documentation/sles-for-sap-12/book_s4s/data/sec_saptune.html

4.3 Other Settings

The XSCS machine gets a dynamic public IP address to be able to access all other machines in the private network.

All machines use the Azure feature Accelerated Network (AN) (only if the VM size supports AN).

All AVSets for the APP machines use a FaultDomainCount of 2 and an UpdateDomainCount of 20.

4.4 Disk Overview

The template uses the following disks and mount points:

Demo

Mount Point

Disk

Size

/hana/data

0,1

128 GB

/hana/log

2,3

128 GB

/hana/shared

4

128 GB

/usr/sap

5

128 GB

/hana/backup

6

128 GB

/sapmnt

7

128 GB

Small

Mount Point

Disk

Size

/hana/data

0,1,2

512 GB

/hana/log

same disks as data

/hana/shared

3

512 GB

/usr/sap

4

64 GB

/hana/backup

5

1024 GB

Medium

Mount Point

Disk

Size

/hana/data

0,1,2,3

512 GB

/hana/log

4,5

512 GB (W)

/hana/shared

6

1024 GB

/usr/sap

7

64 GB

/hana/backup

8,9

1024 GB

(w) uses Azure feature "writeAccelerator"

Large

Mount Point

Disk

Size

/hana/data

0,1,2

1024 GB

/hana/log

3,4

512 GB (W)

/hana/shared

5

1024 GB

/usr/sap

6

64 GB

/hana/backup

7,8

2048 GB

(w) uses Azure feature "writeAccelerator"

4.5 Other Settings and Machines

All machines created with the template use the Azure feature Accelerated Network (AN) (only if the VM size supports AN).

The XSCS machine gets a dynamic public IP address to be able to access all other machines in the private network and only use the base OS disk. There is no additional disk.

The APP server machines use an additional 128 GB disk for /usr/sap/<SID> and the machines are placed in an Availablity Set with a FaultDomainCount of 2 and an UpdateDomainCount of 20.

NOTE: Availability Set

An Availability Set is a logical group in Azure to ensure that the VM resources are isolated from each other when they are deployed within an Azure datacenter. It ensures that the VMs you place within such an Availability Set run across multiple physical servers, compute racks, storage units and network switches. The Virtual Machines are placed then into an Availability Set to minimize the chances that two of them fail or are updated at the same time. This is essential when you want to build reliable cloud solutions and clusters.

The HA template provides two additional instances for an HA NFS server which has an additional disk as share of 32GB.

4.6 Internal Load Balancer and Ports

Special for the HA setup is the use of the Azure Internal Load Balancer (ILB) which is necessary to use virtual IP addresses in Azure. As such, the ILB allows the use of virtual host names and IPs for the xSCS, HA-NFS and SAP HANA pacemaker clusters. Additionally the ILB is providing Layer 4: TCP and HTTP health probes.

https://docs.microsoft.com/en-us/azure/load-balancer/

The selection ABAP uses the relevant ASCS ports, JAVA uses the relevant SCS ports and ABAP+JAVA both of the ports.

ASCS/SCS Internal Load Balancer ports (examples all with instance 00 in bold):

  • ASCS ERS ports : 3300, 50013, 50014, 50016

  • SCS ERS ports : 3300, 50013, 50014, 50016

  • ASCS Ports : 3200, 3600, 3900, 8100, 50013, 50014, 50016

  • SCS Ports : 3200, 3300, 3900, 8100, 50013, 50014, 50016

  • HANA Ports : 30015,30017

  • NFS Ports : 2049

Probe Ports:

  • xSCS: 62000

  • ERS : 61000

  • HANA: 62500

  • NFS : 61000

5.0 Quick Guide to Install SAP HANA on a SUSE Linux Enterprise Server for SAP Applications

This section leads you through the installation of a default SAP HANA on SUSE Linux Enterprise Server.

It does not replace the SAP documentation - PLEASE read the SAP HANA installation documentation.

IMPORTANT: Transfer

You need to transfer the SAP media for SAP HANA to the Azure cloud environment.

5.1 File Share for SAP Media

Azure Files offers shared storage for applications using the Server Message Block (SMB) protocol which is very useful to upload the SAP HANA Media to it and use it from both machines.

https://docs.microsoft.com/en-us/azure/storage/files/storage-files-introduction

To use Azure Storage, you need to create first a storage account.

In the example below, the Azure CLI v2 command line installed on our local machine is used. It is also possible to install it on the virtual machine you have created in Azure.

For more details see https://docs.microsoft.com/en-us/cli/azure/install-azure-cli-zypper?view=azure-cli-latest.

Another way would be to follow the more general steps from https://docs.microsoft.com/en-us/azure/virtual-machines/linux/mount-azure-file-storage-on-linux-using-smb

or using the portal

https://github.com/AzureCAT-GSI/SAP-HANA-ARM/blob/master/UploadToAzure.md

Steps to Create a File Share in Azure

First you need a resource group where the storage should be placed in.

Substitute the --location parameter with the azure region you have chosen:

az group create --name mytestRG --location westeurope

Now you can create the storage account in your resource group:

az storage account create \
    --name hsrsa4sapmedia \
    --resource-group mytestRG \
    --sku Standard_LRS \
    --location westeurope

A good practice is to share the connection string using variables, as you need to add it to every following storage commands:

az storage account show-connection-string \
    --name hsrsa4sapmedia \
    --resource-group mytestRG

Set the AZURE_STORAGE_CONNECTION_STRING environment variable with the output value of the command. You should enclose the connection string in quotes.

export AZURE_STORAGE_CONNECTION_STRING="YOUR_connection_string"

5.2 SAP Media

Installation media for SAP HANA should be downloaded and placed in the Azure fileshare created in the step before. For this we create an own directory called "SapBits".

You need to download the SAP package 51052325, which should consist of four files:

  • 51052325_part1.exe

  • 51052325_part2.rar

  • 51052325_part3.rar

  • 51052325_part4.rar

If you have the files in your download directory on your machine, the command looks as follows:

az storage share create --name mediashare
az storage directory create --name SapBits --share-name mediashare

az storage file upload --share-name mediashare/SapBits --source ~/Download/51052325_part1.exe
az storage file upload --share-name mediashare/SapBits --source ~/Download/51052325_part2.rar
az storage file upload --share-name mediashare/SapBits --source ~/Download/51052325_part3.rar
az storage file upload --share-name mediashare/SapBits --source /Download/51052325_part4.rar

The next steps need to be done on your virtual machine you created for HANA in Azure. Log in to this machine.nius.

Mount it on the SUSE Linux Enterprise Server system in Azure with the command:

sudo zypper in cifs-utils unrar

mkdir -p /hana/shared/SapBits

sudo mount -t cifs //hsrsa4sapmedia.file.core.windows.net/mediashare/SapBits /mnt -o vers=3.0,username=storage-account-name,password=storage-account-key,dir_mode=0777,file_mode=0777,serverino

sudo cp -v /mnt/51052325* /hana/shared/SapBits

sudo umount /mnt

Extract the HANA software

cd /hana/shared/SapBits
unrar x 51052325_part1.exe

If you need the hana software later again, you do not need this step as it is extracted

5.3 HANA Install

Hana requires a few packages installed within SUSE Linux Enterprise Server.

zypper in -t pattern sap-hana

and configuration settings

saptune daemon start
saptune solution apply HANA

There are several possibilities to install SAP HANA, which are detailed in the following sections.

Installation Using the SUSE Installation Wizard

  • Start YaST.

  • Under Software choose the SAP Installation Wizard:

Figure 4 YaST Control Center - SAP Installation Wizard

  • Point the Installer to the directory with the SAP Media from the step above (for example /hana/shared/SapBits/51052325):

Figure 5 SAP Installation Wizard - Directory

  • The sap media get copied to the local machine:

Figure 6 SAP Installation Wizard - Copying Media

  • Say No if you asked for Supplement/3rd-party mediashare:

Figure 7 SAP Installation Wizard - Medium

  • Click Next at the screen asking for SAP add-ons:

Figure 8 SAP Installation Wizard - SAP Add-ons

  • Fill out the four fields for HANA:

Figure 9 SAP Installation Wizard - System Parameters

  • Say No if you are asked for more products:

Figure 10 SAP Installation Wizard - More SAP Products

  • Agree with the question to continue the installation:

Figure 11 SAP Installation Wizard - Continue Installation

  • HANA gets installed and started.

This installation process will take some time - be patient. You will see the log output in the window.

Installation Using the Command Line

The HANA installer will ask for some values.

Answer the questions according to your well prepared sheet with all needed parameters. Do NOT install HANA with a virtual host name, use the physical host name. Double-check before you type!

  1. Install the SAP HANA Database as described in the SAP HANA Server Installation Guide on both machines.

    1. Change to the directory where you have downloaded and unpacked the installation medium ( in our example it should be /hana/shared/SapBits ):

         cd /hana/shared/SapBits/51052325/DATA_UNITS/HDB_LCM_LINUX_X86_64
    2. Start the SAP HANA database lifecycle manager interactively at the command line:

         sudo ./hdblcm

5.4 For 3-tier Templates: How to Connect to the Other Systems

Only the XSCS machine has a public IP address and needs to be used as intermediate hop (jumphost) between your actual SSH target and yourself.

Instead of using something like unsecure SSH agent forwarding, where the data gets exposed at every jump, you can use ProxyCommand to proxy all your commands through your jumphost.

Consider the following scenario:

+--------+    +---------+    /------ | Host A |
| Laptop |--P-| XSCS    |---+
+--------+    +---------+    \-------| Host B |
                              ...
                              \------| Host X |

A configuration like this will allow you to proxy through the jumphost within the admin subnet to HOST A and B, …

on YOUR local system create a ssh config file:

$ cat .ssh/config
Host XSCS
   User adminuser used here as example
   Hostname public-ip-of-xscs
   Port 22 # a non-standard port would be a good idea

Host hosta
   User adminuser
   Hostname private-ip of host a
   Port 22
   ProxyCommand ssh -q -W %h:%p XSCS

Host hostb
   User adminuser
   Hostname private-ip of host b
   Port 22
   ProxyCommand ssh -q -W %h:%p XSCS

etc...
ssh adminuser@hosta

or

ssh adminuser@private-ip-hosta

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  12. Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles.

  13. Delete any section Entitled "Endorsements". Such a section may not be included in the Modified Version.

  14. Do not retitle any existing section to be Entitled "Endorsements" or to conflict in title with any Invariant Section.

  15. Preserve any Warranty Disclaimers.

If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version's license notice. These titles must be distinct from any other section titles.

You may add a section Entitled "Endorsements", provided it contains nothing but endorsements of your Modified Version by various parties--for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.

The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

5. COMBINING DOCUMENTS

You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections Entitled "History" in the various original documents, forming one section Entitled "History"; likewise combine any sections Entitled "Acknowledgements", and any sections Entitled "Dedications". You must delete all sections Entitled "Endorsements".

6. COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

7. AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an "aggregate" if the copyright resulting from the compilation is not used to limit the legal rights of the compilation's users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document's Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

8. TRANSLATION

Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

If a section in the Document is Entitled "Acknowledgements", "Dedications", or "History", the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document except as expressly provided for under this License. Any other attempt to copy, modify, sublicense or distribute the Document is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance.

10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See http://www.gnu.org/copyleft/.

Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation.

ADDENDUM: How to use this License for your documents
Copyright (c) YEAR YOUR NAME.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.2
or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
A copy of the license is included in the section entitled "GNU
 Free Documentation License".

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the "with...Texts". line with this:

with the Invariant Sections being LIST THEIR TITLES, with the
Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.