Hello Praveen,
The DS_System.* log files (under the <DMC_install>/logs directory) contain the all errors related to LDAP.
If you need more details about the LDAP error, you can edit the DS_System_log.properties file under the Config directory, and change the parameter:
LogInitialLevel from 6 (default) to 13 (trace)
And restart DMC.
Once you found the problem, make sure that you change the configuration back and restart DMC again, to avoid too many error messages in the log files.
I do not recommend changing the json file. My recommendation is to setup DMC back to the SuperAdmin, and reconfigure LDAP again.
To change the authentication in DMC back to SuperAdmin, you can use the script according to the DMC manual at:
https://www.ibm.com/docs/en/db2-data-mgr-console/3.1.x?topic=configuration-resetting-authentication
I hope that helps!
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Cintia Ogura
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