[Samba] Unable to create GPO with rc3 and a few authentication problems

[Dmitry Khromov]

> I had encountered a few problems with 2 Samba 4 rc3 DCs serving domain migrated from Windows 2003 R2. I post them altogether, since they look related.
> 
> 1. Unable to create or delete GPOs.
> # bin/samba-tool gpo create somegpo
> ERROR(ldb): uncaught exception - LDAP error 50 LDAP_INSUFFICIENT_ACCESS_RIGHTS -  <dsdb_access: Access check failed on CN=Policies,CN=System,DC=klin,DC=kifato-mk,DC=com> <>
>   File "/usr/local/samba/lib64/python2.7/site-packages/samba/netcmd/__init__.py", line 175, in _run
>     return self.run(*args, **kwargs)
>   File "/usr/local/samba/lib64/python2.7/site-packages/samba/netcmd/gpo.py", line 952, in run
>     self.samdb.add(m)
> 
> I'm not sure if this is a schema or authentication problem. Could someone suggest how should that be investigated?

It looks like in default Windows schema only members of Domain Admins can modify cn=Policies. If one will allow "Domain controllers" group to have rw access too, the LDAP-related error disappears. However, sysvol FS access error will raise (due to the fact machine accounts do not have write permissions on sysvol/fqdn/Policies after samba-tool ntacl sysvolreset).
So, should samba-tool really use machine account for GPO operations?

-- 
Best regards,
Dmitry Khromov