HP CIFS Server 3.0a Administrator's Guide version A.02.01

Backup Domain Controller Support
Introduction
Chapter 5 95
HP CIFS Server and MS Windows server can each function as a BDC
to its own type of PDC.
HP CIFS Server cannot create Security Account Management (SAM)
update delta files. It cannot interoperate with a PDC to synchronize
the SAM from delta files that are held by a BDC.
The Samba 3.0 BDC does not support replication to a PDC. Running
a Samba 3.0 BDC with a non-LDAP backend can have the difficulty
in synchronizing the SAM database. Refer to Table 5.1, Domain
Backend Account Distribution Option, in the Official Samba
HOWTO and Reference Guide for more information on possible
design configuration for a PDC/BDC infrastructure.