(Glue-2408) SLT Integration

SNP Glue™ provides an option to integrate SAP LT with its data extraction framework. This enables you to leverage the existing SLT implementation and provide the ever-growing SNP Glue™ support for multiple targets.

The solution enables you to:

  • Support batch and real-time data integration.

  • Write to multiple targets, leveraging queues.

  • Control load and performance.

  • Deploy SNP Glue™ on a separate box from SLT.

  • Handle new sources/targets in an automated way.

The integration leverages SAP LT SDK to write to custom ABAP-based targets via BADI implementation. The end-to-end process is seamless and automated.

This page describes the configuration required and additional information about troubleshooting and clean-up activities.

For detailed information about implementing these steps, follow the guide from the SAP Note 2652704.

Prerequisites

This scenario requires SAP LT configuration and SNP Glue™ SLT integration Add-on installed on the SAP system.

Note that the following SNP Glue™ Add-ons should not be installed on the SLT system:

  • SNP Glue™ BEx Query Fetcher (BICS)

  • SNP Glue™ ODP Fetcher

Deployment

The solution can be deployed in 2 modes:

  • Standard deployment

  • Separate box deployment

Standard deployment

SLT and SNP Glue™ run on the same SAP system.

The prerequisites for this scenario are the following:

  • Component DMIS_2011_1_731 SP15 or above is present

Separate box deployment

In this deployment, SLT and SNP Glue™ run on separate SAP systems.

The prerequisites for this scenario are the following:

  • SNP Glue™ and SNP Glue™ SLT connectors are imported to SAP LT and the SNP Glue™ Box.

  • RFC communication is enabled in both directions between SLT and SNP Glue™.

  • Component DMIS_2011_1_731 SP15 or above is present in the SNP Glue™ Box.

Configuration Information

Before the replication run

For the replication to start the valid SAP LT configuration needs to exist and the SNP Glue™ SLT setup needs to be preset.

SAP LT configuration

Go to transaction LTRC and click the button New to create a new configuration. The system displays a dialog box where you can specify the settings for the new configuration. Note the following important settings when creating the configuration:

  • In the step Specify Target System, enter the connection data to the target system. Choose RFC Connection as the connection type. In the field Scenario for RFC Communication, select the value Write Data to Target Using BAdI from the dropdown list. If you don’t see Data to Target Using BAdI you have a newer version of SLT which needs you to select OTHERS and choose SLT SDK in the dropdown list. The RFC connection is automatically set to NONE.

  • In the step Specify Transfer Settings, use the input help (F4 help) for the field Application to find the application ZDVD_GLUE. The application is automatically added to the SAP LT customizing when SNP Glue™ transport is imported into the system.

In the newest versions of SLT (2018_1_752 DMIS SP8), Glue replication as the application in the Specify general data tab needs to be selected.
Only after specifying the application, the option to choose SLT SDK as a target system will become available in the type Other.

Preset of SNP Glue™ SLT setup

Via SNP Glue™ cockpit (/DVD/GLUE) access in the menu Tools > SLT integration > Setup maintenance. This will direct you to the SM30 for the table /DVD/GL_SLT_SETT. SNP Glue™ SLT setup needs to be filled before starting any replication in SAP LT.

The Maintain button will enable you to create/edit a setup that will be used for the generation of the SNP Glue™ objects. The fields of the table are:

After the replication run

SAP LT replication will generate SNP Glue™ objects and prepare the data to be transferred to the target storage. In case the created replication for a specific source is no longer required by the user, generated SNP Glue™ objects with SNP Glue™ SLT metadata can be deleted. Also, all actions within the SNP Glue™ SLT integration create application logs.

Container name in lower case (Binary storages)

To create a container on the target with a name in lowercase, profile settings can be used. The name of the profile is one of the parameters of SLT settings. To create a container with the name in lower case and without the prefix, use <SOURCE_TABNAME_LOWER> placeholder instead of <GLUE_TABNAME> in profile settings. If the prefix is desired, use GLUE_TABNAME_LOWER> placeholder.

Unsupported data types - RAW fields

In case the source table contains RAW fields, the type RAW is replaced with data element /DVD/GL_RAW_STRG, which can be added to the data element mapping in the /DVD/SM_SETUP transaction.

Transfer data to target storage

To complete the data transfer the extraction via the generated Extraction Process needs to be executed. For that, the Queue watchdog can be used (if it was set in the SNP Glue™ SLT setup) or the user can manually perform the extraction.

Schema drift

If the source schema was changed for the table already running within the configuration, the target adjustment will be executed automatically.

In case the replication of the data from a source table gets stuck and there are visible errors for the table (such as Migration object has been deleted due to changes in table definition or Replication job canceled by the user (job name/1LT/.. )) it is necessary to manually suspend and resume replication for the table or to deactivate and activate the whole configuration to unstuck the replication.

Update of generated objects

In SNP Glue™ SLT version 2208, the performance of the SLT replication has been improved significantly. This is beneficial, especially when replicating data from tables with frequent changes. This change is relevant for newly created SLT configurations, if you want to also use it on already created ones follow the steps described below:

  1. Update Glue Queue Fetchers

Go to SNP Glue™ cockpit (/DVD/GLUE) and in the menu pick Tools > SLT integration > Update Glue objects.

The screen contains a select option for the Mass transfer ID , a select option for the Source table, and an RFC destination.

The button Show objects can be used for a visual check of the objects that can be updated.

Execute the report to update generated Glue objects.

2. Update Glue Queues

Go to SNP Glue™ cockpit (/DVD/GLUE) and in the toolbar select Queue overview.

Enter filter criteria.

Select desired queues and press the calculate button.

Deletion of generated objects

Via SNP Glue™ cockpit (/DVD/GLUE) access in the menu Tools > SLT integration > Deletion report. This will submit a report for deleting the generated SNP Glue™ objects for the specific combination of Mass transfer ID and source name.

The screen contains a select option for the Mass transfer ID which is mandatory, a select option for the Source table, and the checkbox for Force Delete for deletion of corrupted Glue tables.

The button Show objects can be used for a visual check of the objects before the execution of deletion based on the filled selection.

After pressing the execute button, the confirmation pop-up will be displayed.

SNP Glue™ SLT application logs

To access application logs go to transaction SLG1 and fill screen input Subobject with /DVD/GL_SLT.

Running in production

This section describes things to keep in mind to ensure a reliable data load in production.

Using batch user

A technical user should be used for scheduling replications and other periodic tasks. Role /dvd/glue_user should be sufficient under normal circumstances.

Make sure you use the technical user in the following places:

  1. Glue scheduler /dvd/gls

     

  2. JCO Watchdog /dvd/jco_mng

     

Assigning resources to the scheduler

To maintain proper load times and avoid data getting stuck in queues, you need to assign sufficient resources to the Glue scheduler.

Four parameters can be customized:

Package size: For efficiency, you should keep it sufficiently large, the most frequently used value is 100MB.

Max process runtime (minutes): Once it is reached, the job commits data to storage and finishes successfully, even though there was more data queued for replication. The free background job is then used to run another replication. The example value is 5 minutes. The recommendation can differ based on the target storage used.

Max number of jobs: One Glue replication job can replicate roughly 5MB (ABAP size) of SAP data per second if there is no other bottleneck. Make sure to assign a sufficient number of jobs to be able to handle the load.

Max jobs used for full loads (%): Divides available resources between full loads and delta loads. Initially, when most data replicated is in the initial load, the value should be around 80%. When loads shift to mostly delta, you should lower the value near 30%.

Oracle LOB segments

When cluster tables are used on Oracle, as is the case with Glue queues, but also some SLT functionality, you should periodically run a reorganization of LOB segments to reclaim released space.

See SAP notes for details:
https://me.sap.com/notes/821687 

https://me.sap.com/notes/541538