Help Needed in External LDAP integration with On-prem apigee installation

[SARAVANAN_MURUG]

I am trying to integrate external ldap with on-prem apigee installation. I did the following set up,

conf_security_externalized.authentication.user.store.user.attribute=userPrincipalName conf_security_externalized.authentication.user.store.user.email.attribute=userPrincipalName

But this setup is not working. Management server logs show below error.

ExceptionMapper.toResponse() : Error occurred : Authentication failed for user :

ERROR SERVICES.RBAC - AuthenticationServiceImpl.authenticateAndGetRoleDetails() : Authentication Failed java.lang.NullPointerException: null

Please find the attached logs.txt for the detailed logs. I tried both direct and indirect binding.

Note: After restarting the management server, for the first management API call I got 200 OK response. But after that I always got 401 Unauthorized error.