CMDB reconciliation rules priority

[Tresselt]

Hello. I have a question regarding some weird behavior I noticed with reconciliation rules. This was noticed in a production environment but using easy examples from my PDI.

Lets say I have two discovery sources - ServiceNow and Alitris. In my recon rules ServiceNow has priority 100 and it applies to all attributes. Alitris has priority 150 but it only applies for fqdn field.
In my head, ServiceNow still has priority over Alitris on fqdn, becuase i selected the apply to all attributes option. However this is the result:

If I manually select each and every attribute in my ServiceNow rule, I see that ServiceNow gets 1st Priority when i Preview the Rules. Is this expected behaviour?

[Kieran Anson]

Hi There,

This is one that is often confusing - From the docs

Authorization to only specific attributes in a class

To authorize a discovery source to update specific attributes in a class, create a static reconciliation rule for the discovery source, and list these attributes in the rule. A rule that grants access to specific attributes in a class overrides other static reconciliation rules with an empty attribute list that grants access to the entire class.

[Tresselt]

Interesting! Thanks for the insight. But another weird part (which was the reason I started looking into this) is that it does not seem like the CI is updated by ServiceNow Discovery even tough its not even discovered by the other source with priority 150 on the specific fields.
So for instance, in CMDB: 
Name: Server1
FQDN: ServerOne.country

ServiceNow Discovery:
Name: Server1
FQDN: Server1.Country
After running quick discovery on the specific IP, fqdn does not change. But in the multisource table i see ServiceNow reporting fqdn as Server1.Country. However, when I turn off the 150 rule, and scan again, fqdn gets updated. This is strange as the CI has no relation to that source. Any clues?