Data Precedence Rules

[Rachana Vulli]

I created 2 Data Sources on Server class. Created Reconciliation Rules for the discovery source with one having High priority and the other with low priority but the records are being updated by low Priority Data/Discovery source as well which shouldn't happen in our case.

I also see that there are no records being created in 'cmdb_datasource_last_update' table which might be the cause.

How the records should get created in that table for every data source run.

Also, if that's not the cause, what might be the issue and how to resolve it

Thanks,

Rachana

[CMDB Whisperer]

If there are no records in the cmdb_datasource_last_update table that is because your data sources are not using the IRE to transform the source data.  You cannot effectively manage multiple data sources without IRE, as reconciliation rules cannot be run.  Note that all data sources should be using the IRE.  When the reconciliation rule is processed, the current discovery source looks for records from previous data sources in the cmdb_datasource_last_update table and it cannot compare the priorities of multiple data sources if some of those data sources are not writing to that table. 

Although you can use traditional transform maps with IRE API's to achieve this I strongly recommend using IntegrationHub ETL application.  Although there is a bit of a learning curve the capabilities are much more flexible and reliable, and require less coding.

[mb27]

I'm having the same problem. I've installed Service Graph Connector for SCCM and I don't see any records for data source SG-SCCM in the cmdb_datasource_last_update table.  I thought it would use IRE by default. Do I need to do something for it to use IRE?  

There are no reconciliation rules for SG-SCCM. Do I need to add a reconciliation rule so it uses IRE?

[CMDB Whisperer]

As far as I know you should not have to have reconciliation rules and SGC for SCCM should be writing to the last update table regardless.  All SGC use IRE.  You might want to try checking out this article for suggestions on debugging further.  https://support.servicenow.com/kb?id=kb_article_view&sysparm_article=KB0793220

[Rachana Vulli]

Hi,

I agree we are not using IRE rules for all our data sources and wanted only for few data sources. Is there any other possible way to achieve it only using IRE for few data sources?

Also, How is it possible to make our data sources use IRE rules to transform the source data?