Sharding, 2 instances, each one pointing to a different DB ("default" and "one")
Login in the "default" instance and create a company associated to the shard "one".
Login in the "one" instance and configure some LDAP properties (enable it for example). Save preferences.
DB of shard one is updated. Any other subsequent changes and saving of the properties causes UI to show the values that you firstly saved. DB is no longer updated.