How to troubleshoot Discovery!!

[sanyalshubh]

Our team reports that Discovery is failing to identify some Linux servers, and the CIs are not being created or updated in the CMDB.
How to troubleshoot ?

[Pankaj kr · Accepted solution]

Validate if those linux server are under the ip range of your discovery schedule, check further on the ECC queue and then error tasks. Try these steps, hopefully this will help you in figuring out what is missing.

[Pankaj kr · Accepted solution]

Validate if those linux server are under the ip range of your discovery schedule, check further on the ECC queue and then error tasks. Try these steps, hopefully this will help you in figuring out what is missing.

[Ravi Gaurav · Accepted solution]

Hi @sanyalshubh 

Below steps will help you :-

1. Verify MID Server Health

Since MID Servers execute Discovery probes, check:

• Status: Navigate to MID Server > Servers and ensure the MID Server is Up and Validated.
• Logs: Review logs under MID Server > Log Messages for errors.
• Permissions: Ensure the MID Server has proper access to the target environment (firewall, network, and credentials).

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2. Check Discovery Logs for Errors

Navigate to Discovery > Status > Discovery Log and look for:

• Errors or warnings related to failed authentication, unreachable hosts, or missing permissions.
• Sensor processing errors that may indicate issues with processing returned data.

If Discovery Log shows "No Response from Target", verify network connectivity.

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3. Test Network Connectivity

From the MID Server host, run:

• Ping: ping <target_linux_server> → If no response, check firewalls or VPN settings.
• SSH Test:
  ssh -v <username>@<target_linux_server>
  • If SSH fails, ensure the port (default 22) is open and credentials are correct.

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4. Verify Credentials in Discovery

Go to Discovery > Credentials > Credentials and check:

• Ensure valid Linux SSH credentials are present.
• Run "Test Credential" for a failing server.
• If test fails, confirm the user has sufficient sudo privileges (if needed).

✅ Fix: Add the correct user and grant sudo permissions if Discovery requires elevated access.

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5. Check Identification & Reconciliation (I&R) Logs

• Navigate to CMDB Identification and Reconciliation > Identification Log.
• Look for errors like:
  • Multiple Matches Found (duplicate CIs).
  • No Matches Found (discovery failing to identify the CI).

✅ Fix: Adjust Identification Rules for Linux CIs if needed.

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6. Review Discovery Pattern Execution

If using patterns:

• Navigate to Discovery > Patterns > Linux Server Pattern.
• Run the Pattern Debugger for failing servers.
• Ensure the correct steps are being executed.

✅ Fix: If steps fail, update the pattern to match the environment.

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7. Validate Discovery Schedule & IP Ranges

• Go to Discovery > Schedules and verify:
  • The correct IP ranges are included.
  • Classification phase successfully identifies Linux servers.
• Run Quick Discovery on an affected server to test.

✅ Fix: Adjust IP ranges or Discovery schedules if needed.

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8. Check CMDB Data Integrity

• Navigate to CMDB Health Dashboard and check for:
  • Duplicate CIs
  • Orphaned CIs
  • Outdated CIs

✅ Fix: Run CMDB reconciliation and clean up duplicates.

[JasmineReid]

Thank you so much for the solution, it helped me.