[Samba] Failed to modify SPNs on error in module acl: Constraint violation during LDB_MODIFY (19)

[Adam Tauno Williams]

On Tue, 2016-02-02 at 23:38 +0100, Markus Dellermann wrote:
> sometimes I see following in the logs:
> /source4/rpc_server/drsuapi/writespn.c:234(dcesrv_drsuapi_DsWriteAcco
> untSpn)
> Failed to modify SPNs on 
> CN=PCNAME,CN=Computers,DC=DOMAIN,DC=NAME,DC=NAME,DC=de: error in
> module acl: 
> Constraint violation during LDB_MODIFY (19)

I am seeing a very similar message - Failed to modify SPNs on
CN=TERRINE-WHITE,OU=Terminal Servers,DC=example,DC=com: error in module
acl: Constraint violation (19)

> In the net i found this "explanation":
> 
> "LDAP_CONSTRAINT_VIOLATION 
> Indicates that the attribute value specified in a modify, add, or
> modify DN 
> operation violates constraints placed on the attribute. The
> constraint can be 
> one of size or content (string only, no binary)." 
> 
> Hm, is this triggerd by dns-updates?
> I see this only with two clients
> How can I "debug" this ?
> 
> I am using samba 4.3.4 with bind-dlz
> clients are win7
> 
> Thank you for your thoughts!
> 
> Markus
> 
-- 
Adam Tauno Williams <mailto:awilliam at whitemice.org> GPG D95ED383
Systems Administrator, Python Developer, LPI / NCLA