It is possible to prevent migrations of all objects of a class. If the class is declared with no_migrate attribute set to true (see Section 10.9.3, “Class Attributes”), all instances of the class won't be allowed to migrate. If you create an instance of the class, the object will always reside on the node on which it was created. If you will try to migrate these objects, the Core will log a warning message and discard the migration.