Upgrading from an older samba4 installation.

* Compile the new version of samba4 by following the HOWTO, but do
  not install it yet, and do not run provision.
* Stop any samba process
* Backup your samba4 provision:
  go into the directory where your samba4 provision is stored (/usr/local/samba by default)
  do tar cf $HOME/backup.tar private etc var sysvol
* do make install
* run 'samba-tool dbcheck'

This will do a consistency check of the data, and is all most existing
installations will require.

If you are upgrading from a quite old provision (Samba 4.0 alpha 13 or
earlier) then running upgradeprovision will do an upgrade of security
descriptors, and upgradeprovision --full will perform a more
comprehensive upgrade of the data (including schema and display
specifiers).  This attempts to do a new provision, and to then copy
existing data into that database.

If you are upgrading from a more recent version, particularly alpha16
or later, then it is better *NOT* to run upgradeprovision as the
database format has not changed.

To upgrade from BIND9 flat files to the internal database store for
Bind 9 DLZ, use ./source4/scripting/bin/samba_upgradedns

