ServiceNow Discovery keeps creating duplicate normalized hardware models

[Tad]

A normalized hardware model (Dell Inc. Precision 5000 Series 5540) is defined and a list of CIs created with this model. Discovery = ServiceNow finds an existing CI defined to this model and creates another normalized hardware model with the same name and moves this CI to this new model.  Now there is a new duplicate normalized hardware model name with 1 CI.  

                           Manufacturer               Name                                         Model Number

Existing Model     Dell Technologies        Precision Mobile Workstation     5540
New Model           Dell Inc.                      Precision 5540

Of course both models Normalize to the same name.

This a real issue!  How can models be managed if Discovery keeps creating new ones?  How can this be prevented?  The understanding is with ServiceNow HAM and Content Service that all identical CIs would be created with only one model.

[Scott Halverso1]

I'm interested in what other say. 

I agree, now that there is a hardware mormalization engine there is opportunity to improve the calls to the age old makeandmodeljs script that the OOTB api that decides whether there is an existing model or if a new one needs to be created.  So far the hardware normalization capabilities is only done in arrears, instead of on the way into asset/cmdb.    MakeandModelJS is used whether coming in from discovery or any of the Service Graph connectors.

Article that talks about the best practice use of makeandmodeljs api.

https://support.servicenow.com/kb?id=kb_article_view&sysparm_article=KB0725174

[Tad]

I have discovered a solution to my problem through testing.  It works 99% of the time.  

The solution is NOT to create hardware models manually and allow the ServiceNow MID server to create the model - at least for our environment since we use ServiceNow Discovery.

Once Discovery creates the model, the CIs in the manually created model are moved to the Mid Server created model.  The manually created model is deleted.  Now when the device is Discovered it continues to be updated and remain in the new MID server created model.  This is solved our problem with duplicate models.

We started with 1 model and reviewed the results for a couple weeks.  No duplicate models.  We tested 10 other models and had the same successful result.  We then proceeded to use the same process for the remaining models.  Yes, it took a while but no more duplicates!  Now when the ServiceNow Content Service normalized the model, sometimes it creates models with the same Display Name even though the Name + Manufacturer + Model Number are different.  We can't control the definitions in the Content Service.

Again, we are using ServiceNow Discovery therefore I do not know if this will work with other Discovery tools that are integrated with ServiceNow.

Currently we have 1 Dell model that still causes issues for us.  ServiceNow Discovery keeps creating additional models.  We have tried many test unsuccessfully.

ServiceNow recommends HAM Pro to solve this problem by opting into the Content Service.  We did that and it didn't work!  We found out it was all about who/what created the hardware model.

[Tom Nichols]

HAMPro does not solve the issue.  it's so weird how the normalized values will be the same, but ServiceNow still creates new models anyway.

[Tom Nichols]

We use HamPro and have normalization provided by Servicenow.  However, we still get duplicates.  I have one with "Dell" as the manufacturer and "Server M630" as the model number.  I have another with "Dell Inc." as the manufacturer and "M630" as the model number.

Model number is (weirdly) not normalized, so they would not change, but manufacturer is, but it doesn't make a difference.  BOTH models have the following:

Normalized Manufacturer:  "Dell"

Normalized Product "PowerEdge Server"

Normalized Model "M630"

Even though the normalized values are the same for both, we end up with 2 models, each with a different number of assets tied to it.  What's the point of normalization if you create duplicate models anyway?  

The normalization engine should have rules to realize that 2 models exist with the exact same values and get rid of one (or at least mark it "inactive" and move all the assets).