libnet_BecomeDC() failed - NT code 0xc00020ee

[ericdes]

This is my first attempt to join another Samba 4 as a DC. What would 
cause this error when I do a

 > bin/net vampire samba.example.com -Uadministrator 
--realm=samba.example.com'

as explained on http://wiki.samba.org/index.php/Samba4_joining_a_domain ?

Options:crossRef behavior_version[2]
         schema object_version[47]
         domain behavior_version[2]
         domain w2k3_update_revision[8]
libnet_BecomeDC() failed - NT code 0xc00020ee
Vampire of domain failed: NT code 0xc00020ee
return code = -1

Eric Desgranges
eric at vcardprocessor.com