Skip to Content
avatar image
Former Member

Architecture question on adapter engine?

What is the difference between running a decentral adapter engine and just having J2EE dialog instances?

Is using a decentral adapter engine a viable method of load balancing?

Does anyone have an SAP recommended architecture for load balancing with XI, or practical experience with this?


Jeremy Baker

Add comment
10|10000 characters needed characters exceeded

  • Get RSS Feed

3 Answers

  • Jun 03, 2007 at 06:21 AM


    <i>J2EE dialog instances:</i>

    This is used for load balancing.

    <i>Decentral AE -load balancing:</i>

    I would say, Decentral AE is not for load balancing, please correct me if i'm wrong. Load balancing is the term if the server is down then the processes will be routed to the other servers in order to continue the process without interruption. Am I right, if yes Decentral AE is not for load balancing.

    The min diff btw Central AE and Decentral AE is Central AE will be default once u installed XI. But Decentral AE is installed based on you landscape reqmt. So if you install Decentral AE , then you can route your messages to Central as well as Decentral AE.

    To be much clear, see i'm confguring File-XI-File scenario , in the adapters I can choose either Central/Decentral AE. So that the work load on particular AE will be less. Hence in the above scenario if you chosse Central AE, if its down it will not take Decentral AE to process the message.

    I hope it clears your doubt.

    SAP XI Architecture & load balancing:

    Best Regards,


    Add comment
    10|10000 characters needed characters exceeded

  • avatar image
    Former Member
    Jun 03, 2007 at 06:30 AM

    Well Raj, what your definition of load balancing is partially correct. What you described is typically referred to as High Availabiltiy.

    Load balancing is the distribution of processing to other "servers" to decrease the use of physical resources on a central "instance"

    Let me give an example in the ABAP world, we use dialog instances of the ABAP stack to spread load. Now it so happens that if one is down it will also pass the request to an active DI, so I guess it is HA by nature

    But what you commented on makes sense. I thought a decentral adapter engine was only for outside the firewall or to be used in B2B scenarios (offsite),

    So let me put this question out there, is anyone on this forum using Decentralized AE in their environment, and what are the reasons for doing so?

    Is anyone aware if the architecture team is also using dialog instances for the J2EE and how are they architecting this?

    I know this is a pretty broad question, if anyone wants to discuss off line my email is

    Any help would be appreciated.


    Add comment
    10|10000 characters needed characters exceeded

    • A decentral adapter engine should be used to have a local installation close to the back end system.

      A sceanrio could that between the XI and and the back ends is a firewall and you do not want to allow JMS, file or RFC access through the firewall. Then you can install a decentral adapter engine outside the firewall and have only http(s) calls through the firewall.

      A decentral adapter engine should not be used for load balancing.



  • Jun 03, 2007 at 06:08 AM

    Depending on your XI Architecture if you implemented different types of adapters you may not want the load from each adapter effecting performance of others or your XI environment. Example if your a big EDI shop you might want to split up your load where different your EDI doesn't effect other EDI. Or you may have a EDI adapter server and another type of adapter for example AS2 on another server not effecting each enviornment. If you ad all of this traffic for all of your adapters on one XI environment with multiple applications you could maybe depending on your environment effect performance. AS2 would be a go example you may want this adapter in your DMZ seperating from your XI system within your core network for Security reasons. The use of a decentralize adpater is a decision yous must mak base on your environment needs and requirements.

    I hope this helps.

    Add comment
    10|10000 characters needed characters exceeded