Overview

Discovery didn't get completed and just show the error from the Discovery Log ""SNMP probe timed out. Target is either unreachable or there are no valid credentials for it." 

This issue happens after clone of the instance or clone then upgrade, if Clone Preserve/Exclude settings do not include all child tables of discovery_credentials.

Discovery Credentials - Orphaned cause "SEVERE *** ERROR *** An error occurred while decrypting credentials from instance"

The error message "SNMP probe timed out. Target is either unreachable or there are no valid credentials for it." is only seen in the Discovery log but if the "agent0.log" (MID Server log) is checked, the following exceptions are found:

11/26/18 12:10:22 (830) Worker-Interactive:SNMP-8d6cea70db422300f2a328664a9619c3 DEBUG: Flushing session cache due to credential load.
11/26/18 12:10:22 (939) Worker-Interactive:SNMP-8d6cea70db422300f2a328664a9619c3 SEVERE *** ERROR *** An error occurred while decrypting credentials from instance
com.snc.automation_common.integration.exceptions.AutomationIOException: Unable to retrieve data from instance. This MID may not be validated.
at com.glide.util.MIDServerInfoPayloadDecrypter.decryptPayload(MIDServerInfoPayloadDecrypter.java:25)
at com.service_now.mid.creds.provider.standard.StandardCredentialsProvider.loadCredentials(StandardCredentialsProvider.java:289)
at com.service_now.mid.creds.provider.standard.StandardCredentialsProvider.load(StandardCredentialsProvider.java:256)
at com.service_now.mid.creds.provider.standard.StandardCredentialsProvider.loadIfNecessary(StandardCredentialsProvider.java:268)
at com.service_now.mid.creds.provider.standard.StandardCredentialsProvider.iterator(StandardCredentialsProvider.java:137)
at com.service_now.mid.probe.SNMP.getCredentials(SNMP.java:755)
at com.service_now.mid.probe.SNMP.attemptSNMPv3(SNMP.java:405)
at com.service_now.mid.probe.SNMP.attemptSNMP(SNMP.java:340)
at com.service_now.mid.probe.SNMP.probe(SNMP.java:235)
at com.service_now.mid.probe.AProbe.process(AProbe.java:96)
at com.service_now.mid.queue_worker.AWorker.runWorker(AWorker.java:125)
at com.service_now.mid.queue_worker.AWorkerThread.run(AWorkerThread.java:20)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)

11/26/18 12:10:23 (033) Worker-Interactive:SNMP-8d6cea70db422300f2a328664a9619c3 DEBUG: Flushing session cache due to credential load.
11/26/18 12:10:23 (126) Worker-Interactive:SNMP-8d6cea70db422300f2a328664a9619c3 SEVERE *** ERROR *** An error occurred while decrypting credentials from instance
com.snc.automation_common.integration.exceptions.AutomationIOException: Unable to retrieve data from instance. This MID may not be validated.
at com.glide.util.MIDServerInfoPayloadDecrypter.decryptPayload(MIDServerInfoPayloadDecrypter.java:25)
at com.service_now.mid.creds.provider.standard.StandardCredentialsProvider.loadCredentials(StandardCredentialsProvider.java:289)
at com.service_now.mid.creds.provider.standard.StandardCredentialsProvider.load(StandardCredentialsProvider.java:256)
at com.service_now.mid.creds.provider.standard.StandardCredentialsProvider.loadIfNecessary(StandardCredentialsProvider.java:268)
at com.service_now.mid.creds.provider.standard.StandardCredentialsProvider.iterator(StandardCredentialsProvider.java:137)
at com.service_now.mid.probe.SNMP.getCredentials(SNMP.java:755)
at com.service_now.mid.probe.SNMP.attemptSNMPv1_v2c(SNMP.java:361)
at com.service_now.mid.probe.SNMP.attemptSNMP(SNMP.java:346)
at com.service_now.mid.probe.SNMP.probe(SNMP.java:235)
at com.service_now.mid.probe.AProbe.process(AProbe.java:96)
at com.service_now.mid.queue_worker.AWorker.runWorker(AWorker.java:125)
at com.service_now.mid.queue_worker.AWorkerThread.run(AWorkerThread.java:20)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)

The error is being encountered every time the credentials are being loaded in the system and that happens when Discovery runs. 

Cause

The cause of the issue is there are orphaned records found in the "discovery_credentials" table.

Verify this by navigating to the "Discovery > Credentials", open the credentials and if it shows "Record not found" that is the symptoms that the credential record is an orphan record.

Solution

Identify all the orphan records and delete it.

*** If the records cannot be deleted from the User Interface or via background script, please call ServiceNow support and request to clean up the orphan records in the "discovery_credentials" table. Please quote PRB1305469.

Additional Information

Related to: 

• KB0717208 / PRB1305469 - "Excluding table-per-class (TPC) extended tables from a clone can cause orphaned Discovery Credentials with the 'Record not found' error when trying to open them".
• KB0748823 / PRB1342894 - An error occurred while decrypting credentials from instance - Creating OAuth 2.0 credential results in no credentials being retrieved by the MID server, and Probes will no longer be able to use them