While syncing with LDAP, username collisions should be handled based on an LDAP sync configuration value.
The configuration options should be to indicate the following behaviors
- convert the existing (non-LDAP user) user to an LDAP user
- This is the existing behavior
- skip or ignore the collision, leaving the existing user unchanged
- a new user record should not be created
Note: Future behavior may be to cause the sync operation to fail, but that shouldn't be handed yet.
This configuration value should be set when setting up LDAP sync properties via ambari-server setup-ldap and be enforced when processing the sync operation in methods like org.apache.ambari.server.controller.AmbariManagementControllerImpl#synchronizeLdapUsersAndGroups or org.apache.ambari.server.security.authorization.Users#processLdapSync.