Skip to main content

SAP system migration blog series - part 1: migration overview



Summary:


This blog is part 1 of the blog series on SAP system migration. In this blog, we will provide overview about SAP migration, types of migration, their differences and usage scenario.


SAP migration overview: 


As the Greek philosopher, Heraclitus, said: “change is the only constant.” Same goes within SAP world too, often customer have to change the SAP systems along with its underlying components to meet the changing requirements, be it change from old hardware to new one, changing operating system, database. This change in SAP system components (DB, OS or Hardware) is termed as migration.


Before we go into details of migration, let’s understand architecture of a typical SAP system. 


An SAP system consist of SAP application instances, running on database (DB), hosted on operating system (OS), provisioned on hardware. Change in any one or more of these underlying components (DB, OS or hardware) warrant us to perform migration.



Types of migration: 

Broadly, there are two types of migration: Homogenous migration and Heterogenous migration


1. Homogenous migration: When an SAP system is moved to new hardware of similar architecture while keeping the underlying operation system and database same as source SAP system. 

Homogenous migration is often referred as AS-IS migration because we keep the target system configuration same as source system.




Important points to note: 

    • As rule of thumb, if SAP kernel type is not changing on the target system, then this type of migration falls under homogenous migration.
    • In homogenous migration, OS and Database type remains same in source and target system; however, their version may differ. For example, 
      • Source and target database is HANA but source is on HANA1.0 and target on HANA 2.0.
      • Source and target OS is SUSE Linux, but target OS SUSE version is higher.
      • Source OS version: Windows 2008, target OS version: Windows 2012 R2.
    • Change OS from SUSE Linux x86_64 to RedHat Linux x86_64 (or vice versa) is considered as homogenous migration as both are Linux based.
    • Hardware architecture of source and target server must be same. Thus, homogeneous migration is only possible with the following operating system platforms:

                                            Table 1: Source hardware type vs target in homogenous migration

                 Note: Endianness means the order in which a sequence of bytes is stored in the                                                         computer memory. For more information, see SAP Note 552464.

    • For homogenous migration, DB dependent method (backup/restore, HANA system replication in case of HANA DB, etc.…) or DB independent method (export/import) can be used. We will discuss homogenous migration in detail in upcoming blog.


Examples of homogenous migration: 


    • Shift from on-premises physical hardware or virtual infrastructure to virtualised environment on cloud or another datacenter but keeping OS, DB same.
    • Migrating system from old hardware (e.g., HP RX2800) which is not supported for S/4 HANA to new hardware (e.g., Superdome Flex 280) supported by S/4HANA
    • Conversion from on-premise ECC on HANA to S/4HANA cloud.
    • HANA Migration from scale-up server to scale-out server
    • Migration of SAP HANA from an existing AWS EC2 instance to an EC2 High Memory instance. Similar migration in other cloud providers like Azure and GCP.

2. Heterogenous migration: When an SAP system is moved to new hardware of similar or different architecture while changing either operating system or database or both.

Heterogenous migration is often referred as OS/DB migration.

 



                                                                    *Target has OS/DB/Hardware different than source


Important points to note: 


    • As rule of thumb, if SAP kernel type has to be changed on the target system, then this type of migration falls under heterogenous migration.
    • Hardware architecture of source or target can be different. For any combination other than table 1 shown in homogenous migration section, heterogenous migration is mandatory.
    • For Heterogeneous migration, DB independent method (export/import) is necessary. Also, migration key must be entered into the migration tool. Each OS/DB Migration requires its own key. It is assigned on the basis of the installation number and additional system-specific information. We will discuss heterogenous migration in detail in upcoming blog.

Examples of heterogenous migration: 


    • Change DB from HANA to anyDB (or vice versa)
    • Change OS from AIX to HP-UX or Solaris (or vice versa)
    • Change OS from Unix to Linux (or vice versa)
    • Change OS from Windows to Linux (or vice versa)
    • Change OS/DB from Windows/MSSQL to Linux/ASE (or vice versa)
    • Change from SAP HANA Big Endian to Little Endian (or vice versa).
    • The processor on the target host and source host does NOT use the same byte sorting.                        (little endian -> big endian; big endian -> little endian) like Intel-based to IBM Power Systems (Big-Endian) or vice versa.


Interesting trivia: 


Words- System ‘copy’ and ‘migration’ are often interchangeably used in SAP world. SAP uses mostly the word ‘copy’ (be it ‘homogenous system copy’ or heterogenous system copy’) and terms ‘Heterogeneous system copy’ as synonym for migration.


However, there is slight difference between system copy and migration: 


System copy:  It’s a process where you are copying an existing SAP system to another system which is either already there (like copy production system to quality system, often called system refresh) or copy into a new system like creating test, demo or training system or do homogenous migration to new hardware.


In short, system copy = system refresh/new system build using copy of source/homogenous migration



System migration: It’s a process of moving an existing SAP system to new host for example, moving on-premise SAP system to cloud infrastructure or any other datacenter, moving SAP system from old hardware, OS, database to new ones. 


In short, system migration = homogenous migration/heterogenous migration



Conclusion: 


Hope you have got the clear idea about SAP migration and its type. In the part2 of this blog series, we will talk in detail about homogenous migration, its various migration patterns, pros and cons, usage scenarios and tools to be used.


References and links for further study: 


    • System Copy Guide:
                  https://support.sap.com/en/tools/software-logistics-tools.html
                  ->System Provisioning
                  ->System Copy Option of Software Provisioning Manager


Labels:

Comments

  1. Gadget Portal12 November 2022 at 17:44

    I generally check this kind of article and I found your article which is related to my interest. Genuinely it is good and instructive information. Thankful to you for sharing an article like this. How to start Educational Migration.

    ReplyDelete
  2. KrishnaPhilips28 August 2023 at 05:28

    Excellent blog post! Keep sharing this type of post Thank you very much for this one. custom erp development

    ReplyDelete

Post a Comment

You might find these interesting

How to properly Start/Stop SAP system through command line ?

Starting/stopping an SAP system is not a critical task, but the method that most of us follow to achieve this is sometimes wrong. A common mistake that most of the SAP admins do is, making use of the 'startsap' and 'stopsap' commands for starting/stopping the system.  These commands got deprecated in 2015 because the scripts were not being maintained anymore and SAP recommends not to use them as many people have faced errors while executing those scripts. For more info and the bugs in scripts, you can check the sap note 809477.  These scripts are not available in kernel version 7.73 and later. So if these are not the correct commands, then how to start/stop the sap system?  In this post, we will see how to do it in the correct way. SAP SYSTEM VS INSTANCE In SAP, an instance is a group of resources such as memory, work processes and so on, usually in support of a single application server or database server with
24 comments
Read more

sapstartsrv is not started or sapcontrol is not working

 What is sapstartsrv ? The SAP start service runs on every computer where an instance of an SAP system is started. It is implemented as a service on Windows, and as a daemon on UNIX. The process is called  sapstartsrv.exe   on Windows, and   sapstartsrv   on UNIX platforms. The SAP start service provides the following functions for monitoring SAP systems, instances, and processes. Starting and stopping Monitoring the runtime state Reading logs, traces, and configuration files Technical information, such as network ports, active sessions, thread lists, etc. These services are provided on SAPControl SOAP Web Service, and used by SAP monitoring tools (SAP Management Console,  SAP NetWeaver  Administrator, etc.). For more understanding use this link : https://help.sap.com/doc/saphelp_nw73ehp1/7.31.19/enUS/b3/903925c34a45e28a2861b59c3c5623/content.htm?no_cache=true How to check if it is working or not ? In case of linux , you can simply ps -ef | grep sapstartsrv In case of windows, you need
Post a Comment
Read more

HANA System Replication - Prerequisites & Setup

Hey Folks! Welcome back to Hana high availability blog series. In our last blog we checked out operation & replication modes in hana system replication. If you haven't gone though that blog, you can checkout  this link In this blog we will be talking about the prerequisites of hana replication and it's setup. So let's get started. When we plan to setup hana system replication, we need to make sure that all prerequisite steps have been followed. Let's have a look at these prerequisites. HANA System Replication Prerequisites: Primary & secondary systems should be up & running HDB version of secondary should be greater than or equal to Primary database sever But, for Active/Active(read enabled config), HDB version should be same on both sites. System configuration/ini files should be identical on both sides Replication happe
3 comments
Read more

HANA hdbuserstore

The hdbuserstore (hana secure user store) is a tool which comes as an executable with the SAP Hana Client package. This secure user store allows you to store SAP HANA connection information, including user passwords, securely on clients. With the help of secure store, the client applications can connect to SAP HANA without the user having to enter host name or logon credentials. You can also use the secure store to configure failover support for application servers in a 3-tier scenario (for example, SAP Business Warehouse) by storing a list of all the hosts that the application server can connect to. To access the system using secure store, there are two connect options: (1)key and (2)virtualHostName. key is the hdbuserstore key that you use to connect to SAP HANA, while virtualHostName specifies the virtual host name. This option allows you to change where the hdbuserstore searches for the data and key files. Note
3 comments
Read more

ST03N : The chapter for all BASIS Admins

This blog is targeted to BASIS ADMINS Transaction for workload analysis statistical data changed over time are monitored using transaction code ST03 , now ST03N (from SAP R/3 4.6C) . With SAP Web AS 6.4 the transaction ST03 is available again. From time to time ST03 and ST03N has seen many changes but later in SAP NW7.0 ST03N has reworked in detail specially processing time is now shown in separate column. Main Use of ST03N  is to get detailed information on performance of any ABAP based SAP system. Workload monitor analyzes the statistical data originally collected by kernel. You can compare or analyze the performance of a single application server or multiple application server. Using this you start checking from the entire system and finding your way to that one application server and narrowing down to exact issue. By Default :- You see data of current day as default view , you can change the default view. Source of the image : sap-perf.ca Let's discuss the WORKLOAD MONITOR By D
4 comments
Read more

SAP application log tables: BALHDR (Application Log: Header Data) and BALDAT (Application Log: Detail Data)

  BALHDR (Application Log: Header Data): Usage : The BALHDR table stores the header information for application logs. It serves as a central repository for managing and organizing log entries. Example Data Stored: The table may contain entries for various system activities, such as error messages, warnings, or information logs generated during SAP transactions or custom programs. Columns Involved: LOGNUMBER: Unique log number assigned to each log entry. OBJECT: Identifies the object associated with the log entry (e.g., a program, transaction, or process). SUBOBJECT: Further categorizes the object. USERNAME: User ID of the person who created the log entry. TIME: Date and time when the log entry was created. ADD_OBJECT: Additional information or details related to the log entry. BALDAT (Application Log: Detail Data): Usage : The BALDAT table contains the detailed data for each log entry, linked to the corresponding entry in the BALHDR table. It stores the specific log details and me
Post a Comment
Read more

How to resolve Common Error : Standard Template "sap_sm.xls" missing

Hey everyone, putting forward a common error we usually face when we have “ Excel inplace” functionality enabled in our SAP system. This error occurs when validity of the signature of SAP standard templates expired or were incorrectly delivered via support packages. We can reproduce the error by doing as below.. Click on “spreadsheet” icon after any SAP ALV grid view of data is on screen to make this data to export into excel directly from SAP.
1 comment
Read more

SAP HANA System Replication - Operation Mode & Replication Mode

Hey Folks! Welcome back to Hana high availability blog series. In our last blog we checked out what is hana system replication and how it basically works. If you haven't gone through that blog, you can checkout link In this blog we will be talking about the replication modes and operation modes in hana system replication. So let's get started. When we setup the replication and register the secondary site, we need to decide the operation mode & replication mode we want to choose for replication. For now we won't focus on setting up replication as we'll cover it in our next blogs.  Operation Modes in Hana System Replication: There are three operation modes available in system replication: delta_datashipping, logreplay and logreplay_readaccess. Default operation mode is logreplay. 1. Delta_datashipping: In this operation mode initially one full data shipping is done as part of replication setup and then a delta data shipping takes place occasionally in addition to cont
2 comments
Read more

Work Process and Memory Management in SAP

Let’s talk about the entire concepts that are related to memory when we talk about SAP Application. Starting with few basic terminologies, Local Memory :  Local process memory, the operating system keeps the two allocation steps transparent. The operating system does the other tasks, such as reserving physical memory, loading and unloading virtual memory into and out of the main memory. Shared Memory :  If several processes are to access the same memory area, the two allocation steps are not transparent. One object is created that represents the physical memory and can be used by various processes. The processes can map the object fully or partially into the address space. The way this is done varies from platform to platform. Memory mapped files, unnamed mapped files, and shared memory are used.  Extended Memory : SAP extended memory is the core of the SAP memory management system. Each SAP work process has a part reserved in its virtual address space for extended memory. You can set
7 comments
Read more

ABAP Dumps Analysis

Ever now and then have you heard about ABAP Dumps, We also have a joke everything in temporary in life except ABAP dumps for SAP Consultants. Lets try to understand ABAP dumps from perspective of a SAP BASIS Consultant. Dumps happen when an ABAP program runs and something goes wrong that cannot be handled by the program We have two broad categories of Dumps , In custom program Dumps and SAP provided program Dumps. Dumps that happen in the customer namespace ranges (i.e. own-developed code) or known as Custom Program , can usually be fixed by the ABAP programmer of your team. Dumps that happen in SAP standard code probably need a fix from SAP. You do not have to be an "ABAPer" in order to resolve ABAP dump issues. The common way to deal with them is to look up in ST22 How to correct the error ? Hints are given for the keywords that may be used to search on the note system. Gather Information about the issue  Go to System > Status and Check the Basis SP level as well as info
Post a Comment
Read more