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The LDAP Directory Manager has a Debug Mode (option in the last tab) which is highly recommended to be turned on when configuring the LDAP plugin for the first time or when you are having issues. When debug mode is on, you can find all the search queries performed by the directory manager. They will all be logged into the joget.log files. From there, you can observe the search filter string and improve the accuracy and performance of the lookup. You can remove the debug checkbox once everything is running well.
LDAP Directory Manager Properties
Configure LDAP Directory Manager
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