Discovery not identifying Windows devices that it used to?

[Marcel H_]

I've been having some issues lately with Discovery not identifying Windows devices that it used to find, classify, identify and scan with no problems. Now when scanning a subnet of Windows servers, with known good credentials (I've tested by logging into the servers with the same account running the MID Server service) it will stop in the Identifying stage with a scan status of "Completed 2" and won't identify the CI.

When I check the logs, I get a lot of "Failed Exploring CI Pattern, Pattern name: Windows OS - Servers, To Check Pattern Log Press Here" errors. When checking the pattern log there really isn't anything useful in it:

I then run the Check Pattern debug against one of the same IP addresses, and it completes with no issues. I even did a fresh MID Server install to see if that was an issue, but get the same results.

Has anyone else ever run into issues like this where devices that have always been discovered suddenly can't?

[Ashutosh Munot1]

Hi,

check this:

https://docs.servicenow.com/bundle/orlando-it-operations-management/page/product/discovery/task/t_Id...

https://community.servicenow.com/community?id=community_question&sys_id=d97083e1db98dbc01dcaf3231f96...

Also check the Windows Identifier as well. As mentioned in above script.

https://hi.service-now.com/kb_view.do?sysparm_article=KB0539839

This explains the issue.

Thanks,
Ashutosh

[Marcel H_]

Thanks so much for the direction on this. I've been able to solve quite a few issues, especially after comparing what is in our production instance vs my personal developer instance.

We still have a lot of devices that aren't being discovered, but most likely because they are devices that aren't classified OOB like IP Phones, A/V devices, security devices, etc.

[DuaneNMore]

Go to the Input Queue of the HorizontalDiscoveryProbe Pattern Launcher: Windows OS - Servers from the Discovery. Open it up and go to the Payload.

Take everything from the curly brace before "items" all the way through the penultimate right curly brace before </output>.

Realistically you may have to go to a JSON validator site to get this completely right. I happen to use https://codebeautify.org/jsonviewer.

Once you have something good, go to "Identification Simulation", go to "Start with Existing Payload". 

Select Data source ServiceNow and paste "good" JSON payload in and hit "Run Simulation" If something is busted in the Output Payload this will pick it up.

Hope this helps! Discovery of this has saved my bacon a number of times.