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Author's profile photo Tomas Black

Exploring the “Switch expert mode on” feature during Upgrades and EhP implementations

     This Wiki Article explains a feature from SUM tool (Software Update Manager) called Switch expert mode on, which, when enabled, make several options available to customize and optimize the upgrade process.

     On the initial steps of the upgrade, SUM stops in phase PREP_CONFIGURATION/INITSUBST asking for some customers inputs, as seen below:



     By checking this option, you will be able to:

  • adjust manually the Support Packages set to be imported in phase BIND_PATCH, even if this is not necessary;
  • change the shadow instance host (providing the ability to use a remote shadow instance) and shadow instance number (which is automatically generated);
  • remove installed languages or their respective components that SUM does not find the appropriate DVD;
  • use saved profiles from a previous update for the shadow instance.


     You can find this information on the SUM guide. As of August/2015, the latest version is SUM 1.0 SP13. It is described on page 56, on the following link (ABAP only, Windows X64 + Oracle):     


     Please select the appropriate guide according to your system needs (ABAP+Java or Java only) here.


     The Near Zero Downtime (nZDM) feature is available only if the ADVANCED mode is selected (as it is on the screenshot above), as seen on the guide:

“The Software Update Manager (SUM) is equipped with the near-Zero Downtime Maintenance (nZDM) technology. This technology includes features in the Advanced preconfiguration mode settings to minimize the Business Downtime while applying …

     This is the screen you get for the Near Zero Downtime feature in SAPGui. nZDM is a feature introduced recently in SUM aimed to reduce the overall downtime during upgrade. Please refer to note #1678565 for more information about it, as well as the following links:


     Regarding the parallelism feature:  you can always select the number of processes for the different processes, independent of the Preconfiguration mode selected or the selection (or not) of the Expert Mode.

Please refer to note #1616401 for complete information about this feature within SUM, SPAM, SAINT and other tools.


     If you have not selected ADVANCED, you’ll be prompted to select the number of parallel process and proceed to the option to select a different host to run background jobs, or let the tool select one automatically. The system will list as many hosts as available, just make sure to have directory ../SUM/abap mounted on the selected server! Also note that, during downtime, the background jobs will be started mandatory on the Central Instance (or Primary Application Instance), and any other background host will be shut down. Please refer to these HELP.SAP links to ensure your background server is correctly configured:

Activating Background Processing

     You can also select to use the “Memory Optimizer Activator” feature. Please refer to note #1630256 for its complete explanation and usage.Regarding the “Downtime-minimized” strategy, if you opt to run the shadow instance on a different host, please make sure you have a working HARDWARE KEY, as explained in note #1867710.


     Then you have the option to select the remote shadow instance, in case you have opted to run it on a different host. Enter the hardware key as explained on the note above.


     On the next screen you have the ability to use ICNV (Incremental Table Conversion) to perform table adjustments (conversion) during the uptime. Incremental table conversion lets you perform conversions before the upgrade downtime portion, that is, during production operation (uptime portion). The benefits of this procedure are the reduced overall downtime, simpler conversion back to SAP standard for modified tables and conversion of large tables without affecting production operation. Please refer to this HELP.SAP link for more information about ICNV.

     ==> BEWARE that if you use nZDM, ICNV will be switched off automatically by SUM!  <==

     Also you have the option to update the Dialog Instances during the upgrade, if you mark the checkbox “Update Dialog Instances”. In older releases you had to reinstall them using the installer tool (sapinst).


     You also have the option to select the SGEN strategy and its number of parallel process:


    Beware that running SGEN during upgrades is different than running it after the procedure. If you opt to run SGEN afterwards, you’ll have more options to set it up and configure it according to your needs. Please refer to the following links for more information:


      Lastly, you can uninstall any non-standard languages from your system in phase LANG_SELECT, by just unselecting them, as seen below:



     In case you want to rectify values you entered earlier on, you can stop SAPup and restart it with some options that will enable specific parameters to be reedited.     Please proceed as follows:

  1. Stop the upgrade program by choosing “Update -> Stop update” from the main menu of the installation GUI;
  2. Choose “ABAP-> Start With Options” from the menu;
  3. Enter the desired command and press “Execute”. Check below the list of available commands and what they do;
  4. After you have changed the parameters, restart the program

–> Options

SAPup set confpar
this option will allow you to enter again the Archive Mode option, Number of parallel processes and option to Update the Dialog Instances:





     You can also run this command directly on the OS level, you’ll be able to reenter these values. The only difference is that there will be no SAPGUI.

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      Author's profile photo Eduardo Rezende
      Eduardo Rezende

      Hi Tomas,

      Very good your document!
      Keep sharing.



      Author's profile photo Former Member
      Former Member

      thanks for this excellent article

      very usefull and clarifying!

      Author's profile photo Srinivas Kakarla
      Srinivas Kakarla

      Excellent compilation of SUM advanced features. thanks much !!

      Author's profile photo Former Member
      Former Member

      Hi Thomas

      Sorry this is my SUM, but where is the menu : choosing “Installation -> Stop Installation” from the main menu of the installation GUI? Is maybe update -> stop Update?

      Thanks in advance



      Author's profile photo Tomas Black
      Tomas Black
      Blog Post Author

      Hello Sandro

      you're right. It is option "Update" --> "Stop Update", I'll update the information accordingly.

      Best regards,

      Tomas Black

      Author's profile photo Former Member
      Former Member

      Hello Tomas

      Thanks for the quick reply.

      Best regards


      Author's profile photo Former Member
      Former Member

      Hi Tomas,

      Looking for your suggestion/education/knowledge on INITSUBST phase where we define Work-processes for parallel processes. We will be using nZDM option for SP and EHP deployment on various our systems like ECC, CRM, SRM, SCM , BW systems. so its very critical for us to zero on the principle that we need to follow while defining workprocesses.

      What's the 'Thumb rule' to follow while defining the NOs of workprocesses for varies areas?

      Which are the areas more critical that leads for system performance?



      Author's profile photo Tomas Black
      Tomas Black
      Blog Post Author

      Hello Sekhar,

      the tool brings some default values, which I suggest to keep on the initial test upgrades.

      (the general recommendation is 1 parallel process per CPU)

      You can increase the number accordingly:

      - R3load numbers should be high if you're doing DMO. If your system has ~128 CPUs (including the cores - see ST06), you can safely use 100+ R3loads - actually you could try 3-5 processes per CPU. The R3load is smaller when compared to with the load on database, so the number or tp/R3trans should be smaller.

      - R3trans processes should stick to the  1 x 1 (processes x CPU)

      - Batch jobs rely on the capacity of the server to handle them. PARCONV uses this feature, and this phase is one of the most crucial during downtime. On this case I suggest to stick to the default value and change it on the test upgrades, to compare downtime processing results.

      Best regards,

      Tomas Black

      Author's profile photo Brahama Kroma
      Brahama Kroma

      What are the #s of CPU, Memory, etc.. needed for such configuration? Performance is the major concern if you have this as an issue starting the upgrade of EHP. Another concern is how long will the upgrade take based on nZDM if you keep up with the alerting script for every intervention during the upgrade?



      Author's profile photo Tomas Black
      Tomas Black
      Blog Post Author

      Hello Brahama,

      see my reply to Sekhar above for the parameters of SUM tool.

      Regarding seizing of the server (# of CPUs, memory, etc), I don't have an official recommendation, I only recommend values and settings for the UPG tool based on what the server can provide.

      What do you mean by  "if you keep up with the alerting script for every intervention during the upgrade?"  with nZDM? Which alert scripts?


      Tomas Black

      Author's profile photo Brahama Kroma
      Brahama Kroma

      Great job on this document Tomas 

      Author's profile photo Brahama Kroma
      Brahama Kroma

      Thanks Tomas, your reply to Sekhar did answer my questions.


      Author's profile photo Tomas Black
      Tomas Black
      Blog Post Author

      Hello Brahama Kroma and CHANDRA KANIMENI, you can refer to KBA #1616401 for further information regarding parallelism and performance under upgrades/updates.