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EM 13c, 12c: Known Issues in the Discovery of Database and Listener Targets in Enterprise Manager 13c and 12c Cloud Control (Doc ID 1543745.1)

Last updated on DECEMBER 02, 2021

Applies to:

Enterprise Manager for Oracle Database - Version and later
Information in this document applies to any platform.


To understand the usual causes of database and listener targets not being discovered as expected.  
To supply troubleshooting steps to debug the discovery script.

Note: This note concentrates on single instance databases and listeners; for RAC discovery issues, see <note:1432013.1>


Troubleshooting Steps

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In this Document
Troubleshooting Steps
 Known Issues
 1. oratab problems.
 2. $TNS_ADMIN/$ORATAB env settings
 3. Problems with the format of the listener.ora.
 4. Problems with permissions on the listener.ora.
 5. Database/Listener Target Already Exists
 6. Database Details Are Wrong
 7. Database Discovery Failed With 'EMD_URL is Invalid'
 8. Database Discovery Fails on Test Connection with Error: Connection Failure may be due to a slow network
 9. Database Discovered Name is 'Wrong'
 1. Check the entries in <Agent Base>/agent_inst/sysman/log/emagent_perl.trc.  
 2. If nothing seems obvious from the above, then it's possible to trace the discovery in DEBUG mode.
 3. If there are no entries such as "" and "Start of Database and Listener Discovery" in the emagent_perl.trc.
 a) Check whether the database discovery module has been disabled (if using auto-discovery or "run discovery now")
 b) Check whether any other discovery metrics have been run in emagent_perl.trc (if using auto discovery)
 c) Check whether the discovery plugin exists (if using "discovery via guided processes" or all targets/database/add database)
 4. Interpreting the Output of the Discovery Debug Trace 

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