UPDATE: I ended up rebuilding a new Ambari server and database from scratch, and running the 'sync-ldap' command using the default credentials (admin:admin). I think changing the default credentials before syncing the LDAP users causes the sync to fail, will try to raise an issue about this in Github. Thanks @Jay SenSharma and @Vipin Rathor for your help! I used your suggestions when I rebuilt Ambari and they were very helpful! ... View more