[Samba] DC Upgrade from 4.1.7 to 4.6.7

[HB]

> -----Message d'origine-----
> De : samba [mailto:samba-bounces at lists.samba.org] De la part de Rowland
> Penny via samba
> Envoyé : lundi 21 août 2017 16:34
> À : samba at lists.samba.org
> Objet : Re: [Samba] DC Upgrade from 4.1.7 to 4.6.7
> 
> On Mon, 21 Aug 2017 15:52:01 +0400
> HB via samba <samba at lists.samba.org> wrote:
> 
> > Hello all,
> >
> > Our Samba AD DC is running perfectly for years with the following
> > basic setup (see smb.conf below) :
> >       - one DC running Samba 4.1.7 / CentOS 6.5 (compiled from
> > sources)
> >       - internal DNS
> >       - this DC is also a Print Server
> >       - about 400 PC workstations (mainly win7 Pro / win10 Pro and
> > some XP Pro), and about 300 users
> >       - several Synology NAS file servers joined as domain members
> >
> > Since 4.1.7 is quite old, I would like to upgrade to the last stable
> > Samba 4.6.7.
> > I wonder what is the best way to make this upgrade without any risks
> > to break the links between PCs and the domain in production.
> >
> > I see two alternatives :
> > 1) As described in Wiki > Updating_Samba :
> >      Upgrade the running DC :
> > 	- Compile the last stable release 4.6.7
> > 	- stop samba
> > 	- install 4.6.7 over the 4.1.7
> > 	- make the Database Check and fix errors if any
> > 	- restart samba
> > In this alternative , would it be much careful to gradually upgrade to
> > each major release after some tests between each (4.1.7 to 4.2 then
> > 4.2 to 4.3 , ... , then 4.5 to 4.6) ?
> > Or install directly 4.6.7 over 4.1.7 should not cause any problem ?
> >
> > 2) Add a new DC :
> > 	- create and add a new DC based on samba 4.6.7 (CentOS 7) to the
> > domain
> > 	- transfer the FSMO roles from old 4.1.7 DC to the new DC (no
> > incompatibility between 4.1 and 4.6 ?)
> > 	- replicate the sysvol dir to the new DC
> >
> > 	after validation that everything is ok , either :
> > 	- demote the old DC
> > 	- or upgrade the old DC to 4.6.7 also and keep it as secondary DC
> >
> > My questions are the following :
> > - Are my two alternatives correct ? Any comments are welcome .
> > - Are there any problems I have to anticipate ?
> > - What would be your advices to make this upgrade the most secured
> > way, knowing that the DC is in production and my absolute priority is
> > to have no implication on the clients. I can schedule the operation
> > out of worked hours, but I can't assume any interruption during the
> > opened days.
> > - The current DC is also a Print server, is there an easy way to
> > change a DC to a simple Domain member (that keeps the print server
> > role)?
> >
> 
> Normally, both of your suggested ways would be valid, but, because of the
> big jump between versions and the large amount of changes that have
> occurred, I would tend to go with your second option and add a new DC and
> then demote the old DC.
> 
> You cannot directly demote a DC to a Unix domain member, you would have
> join it to the domain, so I would take this chance to update the OS and then
> set up Samba etc as shown on the wiki.
> 
> I would also consider adding a second DC, just in case.
> 
> Rowland

Thanks Rowland for your advice.

In order to transform the old DC + Print Server to a member print server , I plan the following operations : 
1- transfer the FSMO roles to the new DC 
	New-DC# samba-tool fsmo transfer --role=all 

2- demote the old DC 
	Old-DC# samba-tool demote -Uadministrator 

3- stop the samba service 

4- change smb.conf for a domain member 

5- join the the domain 
	Old-DC# net ads join -Uadministrator 

6- Start winbindd , smbd, nmbd services 

Am I correct ?  

Will I have to recreate printers and upload the printer drivers again or will all the print stuff remain from the old DC configuration? 

Thanks a lot.