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Zero Downtime Option of Software Update Manager

In this blog the Zero Downtime Option was introduced.
The most recent updates on Zero Downtime Option of SUM can be found in the following blog post: Zero Downtime Option of SUM (ZDO) is “available on request”.


In SUM we call the new zero downtime maintenance (ZDM) procedure “Zero Downtime Option of SUM (ZDO)”. Since January 2015 the next step to reduce the overall business downtime for updates, upgrades and also customer releases was available for pilots. With help of our customers in meanwhile more than 60 updates/upgrades we tested successfully the zero downtime procedure in customer PoCs and productive landscapes.

In close cooperation to our customers the CoE / Consulting colleagues did an excellent job and in all these customer projects mainly in North America and Europe we shared the knowledge about ZDO. 


With SUM 1.0 SP16 that is available since February 2016 the ZDO procedure is available on request.


What can you expect from ZDO?

The new zero downtime procedure is a new procedure of the Software Update Manager (SUM). So you just continue with the tool you use anyway and know in detail. The new zero downtime option of SUM (ZDO) abolishes the technical downtime and finally enables a business downtime of down to zero. So it is a big step towards serving the increased business requirements of the availability of logistics systems.


With zero technical downtime and almost zero business downtime the costs of maintenance windows will be reduced significantly. It is easier to schedule additional maintenance windows, e.g. to install a feature pack or a new release when the business requires new functionality. With ZDO, upgrades can be performed at any time and any frequency. Thus maintenance planning can react more flexibly and the innovation adoption timeline becomes shorter.


The ZDO procedure supports SAP updates / upgrades and custom development activities as well.

ZDO-use case.JPG

The import of custom transport transport requests is available in SUM since SUM 1.0 SP14 (standard and advanced mode) and this is used for ZDO as well.



How does it work?

With ZDO of SUM SAP architects found a smart solution to manage the conflicting database table access between the update and the user without the need of a system copy. Only a small subset of DB tables has to be copied. The additional DB space is in the range of the existing SUM features for downtime minimization.

The huge difference with ZDO however is, that end-users now run their business while the upgrade is completely executed. The conflicting DB table access between the update and the users is managed on the database layer and is hidden from the end-users as well as from the administrator.
The zero downtime option intends to support customer update or customer upgrade activities on a regular basis. It has to be comfortable in use with minimum costs and acceptable effort for the IT team. The zero downtime technology is integrated in SUM (Software Update Manager). It is therefore equipped with a proven automated procedure and uses the new UI. The zero downtime technology furthermore needs a minimum footprint of DB space when big systems need to be updated several times a year. Thus the zero downtime option does not work with a clone-based architecture. The zero downtime technology works “in-place”. All actions are performed within the same database, and the upgrade and production get different views on the tables.



With zero downtime we refer to the update procedure end-to-end. This means that we also consider the subsequent activities that are usually scheduled after SUM has run, e.g. customer transport requests, cool-down or ramp-up.

Regarding customer transport requests you maintain the transport buffer in the configuration screen and all imports of this buffer, no matter if it is related to e.g. SPAU, DDIC, development or customizing are considered. The SUM imports the transports with import_all. In standard or advanced mode you get all transports related to repository in uptime (shadow), non-repository transports are managed by the SUM as well but have to be imported during the downtime phase. In ZDO even all customer transports are imported in up time.


So the ZDO covers all your big releases no matter if it is an SAP update or a customer release.

After the update when SUM has successfully upgraded the system during up time, the current version of ZDO needs a small period of business downtime. Users cannot work on the old software version in parallel to the new software version. Currently all users have to log off and log on again. A quick restart is needed at this time.



Which products and maintenance activities are supported?

The following graphic shows the technical details about the first shipment of zero downtime in SUM (status December 2016):


This is the availability according to current planning and can be changed at anytime.

You need to read the SAP note 2163060 to get all details about “available on request”.


In focus of the zero downtime option of SUM are the most downtime critical SAP products and Add Ons. If you miss an add on or product here, it is appreciated when you tell us your planning.

Due to technical reasons a BW or an embedded BW is not supported.


Thanks to a big variety of pilot projects we consider different stacks on different databases for the zero downtime enablement. So most of the databases already support the ZDO technology. The databases in green will “be available on request” according to current roadmap


Restrictions of ZDO enablements:

– SAP EWM is currently restricted to installations on SAP NetWeaver only



What does “available on request” mean?

 The most common products and database combinations are “available on request” and are available for your tests and productive upgrades without any additional costs.


For detailed info see SCN article Zero Downtime Option of SUM (ZDO) is “available on request”

and read SAP Note 2163060 – “Prerequisites and Restrictions of Zero Downtime Option of SUM” to get all requested info.



What does “on project basis” mean?

“Available on project basis” refers to a restricted shipment phase. It ensures a direct support for customers and developers get feedback that is needed to validate and improve the new technology close to business continuity. The update project with ZDO is based on a service contract.

This means SAP Support (AGS) or SAP Consulting have to be involved. The software life cycle development team will support your update/upgrade project directly in close cooperation with SAP Service / SAP Consulting and the customer.


In about 60 update executions on customer side this pilot setup was proven. It ensures a direct onsite support for the first PoC activities, enables the know-how transfer, supports your cookbook improvements / adaptions to get the best benefit of ZDO and finally ensures a direct and very fast support from the SAP development team.


Are you limited regarding the use case of ZDO in a pilot project?

Not at all. The first pilot  in January 2015 was performed in U.S.A. with 2 PoC iterations The first productive upgrade on SAP HANA for the internal project system (ERP) at SAP in May 2015 was the start for a roll-out to all critical system in the SAP company. In September we celebrated the first ERP update on customer side.



Do you want a deeper insight?

If you want to get further information about how ZDO works in detail and would like to be one of the pilot project participants in the next months, feel free to get in touch with @jensfieger (Product Manager Downtime Minimization of Cloud & Lifecycle Management).

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  • Hi Martin,

    Great news.

    I'm in the middle of an EHP7 upgrade and I'm already using the nZDM feature.

    We are running several mocks because the UPG is integrated into an UC + Migration that are being done in one shot only.

    It is possible to test the ZDO? is it already available for ECC in ramp up?

    Can you send me more details, thanks in advance.



    • Hi Antonio,

      with zero downtime in SUM we started with the approach to consider the whole business downtime. So we considered discussed the cut over planning of several companies and considered customer transports and also tried to optimize the cool down.

      However migration activities are not possible. These kind of projects still need the clone concept.

      Of course, it is possible to test. In parallel to our development activities we had proof of concepts with customers to get their feedback at an eraly stage and to see the preocedure running on systems outside SAP.

      When we ship it and start the "available on projects" we talk with customers and real cut over projects. When we see the need to have a kind of RKT session I will take care about. What is your idea? How do you want to test?

  • Hi Martin,

    Definitely like to get further info, especially what's the technology used and processes running behind ZDO!

    Hope to hear from you soon!


    • Hi Nicholas,

      are you at the d-code? I will explain architectural details and customer experience in a d-code session (ITM207)

      And it is possible to arrange a webinar call. Usually I would arrange this with help of the ASUG or DSAG.

      And finally I will publish further info in the next months, of course.

      Best regards,


  • Hi Martin,

    I see that the bar set for start releases supported by ZDO is quite high - EhP7 for ERP, etc.

    Will we see ZDO being used for lower releases? Eg. ECC 6.0?



    • Hi Ajay,

      sorry for late reply. I was in vacation.

      And I agree, the start release to use ZDO is quite high. Main reason is, that for the ZDO architecture to manage an upgrade instance in parallel to a productive instances several development activities in SAP NetWeaver were needed.

      We discussed if we move the coding to older SAP NetWeaver releases as well. However this is not easy and we estimated a long project duration for this. But this means, that when the functionality would be available for older SAP NetWeaver releases as well, the today new releaase would have been a major release for many customers anyway. Therefore we decided to keep the SAP NetWeaver release as it is and spend the capacity in customer projects and use it for enablements of other SAP products.

      Best regards,


  • Hi Martin,

    this new option is very important for a lot of our customers in healthcare area with 7 x 24 service needed, but they oftenly have older non-unicode installations. Is it planned to reduce this restriction to unicode systems?

    Best Regards


    • Hello Helmuth,

      at the moment we only support unicode systems. It is an additional internal development project to support non-unicode systems. And the support is not on the shortterm list. However it might be very helpful to get direct customer feedback and demand for zero downtime for non-unicode systems as well.

      I would appreciate some more insights. So please get in conatct with me.

      best regards,


  • Hello Mr Herrmann,

    Can you provide some information on what addition resources i.e Disk storage, Memory, CPU need to use the ZDO option.  I am putting together a comparison of the different methods (Standard, NZDT, and ZDO).  Can you send me a copy of you dcoded-code session (ITM207) on architecture examples?



    • Hello Thomas,

      since November 2014 we are in customer projects / PoCs and we definitely need some time to get key figures about DB size and CPU comparing to SUM standard or advanced mode for example.

      However as said it is an in-place approach. The DB size should be comparable to the SUM advanced mode (nZDM activated). For SUM advanced mode (incl. nZDM) processes are needed for the record and replay technology. And even with this technology CPU was not a topic. And this technology is not used for ZDO. I don't see any issues here.

      But again final results need a big variety of runs. And each customer needs to check it in his environment anyway.

      Best regards,


  • Hello Martin,

    Is there a difference between nZDM and ZDO? If so where can I get more insights on this difference?

    Any info regarding this will be of great help.

    Thanks and with best Regards,

    Anusha R

    • Hi Anusha,


      the procedure is compeltely different and the technology as well. We invested a lot to be able to run the sub-system interaction, to get a smooth V1-v1 transfer and to enable all AIMs for a parallel update to the users.

      Please send me an email and I send you some details about.

      Please tell me also via email which info you need, so I will add it in SCN as well.


      Best regards,


    • Hello Martin

      Appreciate if you could send the differences between nZDM and ZDO to my mail-id,

      I have a couple of queries surrounding this topic and probably the docs help me understand better, as i could hardly see any technical documents on the this topic in net.



  • Hi Martin

    Thanks for the excellent information.  Would you know if we can combine Oracle 12c upgrade and ZDO/nZDM ?

    Will it also work with different OS ( for now Linux 5.x to Linux 6) or from HP-UX to Linux 6.

    Thank you

    Santosh Lad

    • Hello Santosh,

      sorry for very late reply. I answered but obviously I had technical issues. Now the answer: the ZDO is focused on ABAP and like all other features and procedure in SUM it considers the all-in place approach. This means it is always the same DB but only different schemas. With this architecture a DB upgrade in parallel is not feasible. For this a clone approach is needed.

      Just to show and explain the different options I published the following article:

      Minimizing planned downtime during maintenance

      Best regards,

      Martin Herrmann

  • Hello Martin,

    Is there already a roadmap for Zero Downtime Option?

    ZDO is a very important feature for one of our customer.

    If this feature can not be implemented, the customer thinks about changing the software-supplier.

    Best regards

    André Reinsch.

    • Hello André,

      at TechEd in October / November this year I published the current roadmap regarding availability and functionality of ZDO.

      I have updated the blog accordingly. Please check if this is feasible for your customer

      Best regards,


  • Dear Martin,

    Does SAP plan to combine ZDO with DMO ? I think this very important for customer that would like to migrate to S/4 HANA but they have very limited business downtime.

    Thanks and Best Regards


    • Dear Tamizee,

      I completely undertsand your question and of course our customers need to consider the downtime when they start a conversion project to S/4HANA.

      But ZDO is not the donwtime optimization procedure for this. For the conversion we mainly need to consider optimization with help of the shadow.

      Boris Rubarth is the responsible Product Manager for DMO.

      Best regards,


    • Dear Tamizee,
      ZDO is not an option for the system conversion from SAP ECC to SAP S/4HANA. We do work on reducing the downtime for the system conversion, but when mentioning ZDO you have to keep the relations: a system conversion is a different story than an update/upgrade.
      Best regards, Boris

      • Dear Boris,

        Thanks for clarification regarding differences of ZDO and DMO. Looking forward to hear further announcement of reducing downtime for system conversion 🙂 .

        All the best.

        Best Regards