Adding objectClass to existing dn

Michael Ströder michael at
Tue Feb 1 15:34:43 CET 2005

Robert Cooke wrote:
> I've been trying to add an objectClass to an existing dn.
> Now I get messages like :
> {'info': "attribute 'cn' not allowed", 'desc': 'Object class violation'}
> {'info': 'modify/add: objectClass: value #0 already exists', 'desc':
> 'Type or value exists'}
> In my modlist are all the values nessecary I though. It feels like
> the chicken and the egg problem.

There's no chicken and egg problem here. The error description says that 
the attribute value for attribute 'cn' is already there. To be clear: 
Not only the attribute 'cn' itself is present. The very same attribute 
value is already stored in attribute 'cn' of this entry. This violates 
the X.500 data model. Just leave the 'cn' out of your modify list.

> To insert an objectClass you need the must attributes and to get the
> attributes you need the new objectClass.

This is another problem and can be easily solved. Add and modify 
requests are atomic.

Ciao, Michael.

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