How to avoid updating the install status by Discovery?

[Giovanni Eggidi]

Hi,

we have discovered about 12000 servers on a client project (Windows, Linux, vCenter).

With our Discovery we are overwriting the data imported manually from their old database. Discovery. In some cases the ServiceNow Discovery also modifies the install status to "Installed", but this field must remain unchanged from the previous value fill manually. 

What is the best way to prevent any changes on this field for all CMDB classes in ServiceNow?

Thanks & Regards, G.

[Kieran Anson]

A reconciliation rule would be used to manage this. These rules specify what data sources can override the values of other sources, and which attributes are overridable. 

https://docs.servicenow.com/bundle/xanadu-servicenow-platform/page/product/configuration-management/... 

[Giovanni Eggidi]

Hi Kieran, i agree with you, but I have an issue. In my case, I would like ServiceNow Dicovery to update all fields except the "install_status" for any CI Class. How should I do it? Should I create a reconciliation rule for each class, and insert all attributes except the "install_status"?

[Kieran Anson]

Reconciliation rules are inherited, so you could set a rule on cmdb_ci, that information is covered in the docs linked previously 

[Giovanni Eggidi]

Ok, I understand, but i have a specific question that is not mentioned in docs.

If I Create a Reconciliation Rule for Discovery selecting all fields of "cmdb_ci" table without "install_status" field (deselecting this field) and then I create another Reconciliation Rule for Import Set leaving the Field Attribute Empty (ALL attributes), what happened after discovery of everyone child class on the specific attrubutes which are not in root table "cmdb_ci"?