[Samba] Questions on this upgrade scenario

[Rowland Penny]

On Mon, 27 Nov 2023 15:24:06 +1300
Andrew Bartlett via samba <samba at lists.samba.org> wrote:

> On Sun, 2023-11-26 at 21:03 -0500, James Johnson via samba wrote:
> > Hello!
> > I've encountered a CentOS 6.10 server running Samba 4.1.0 compiled
> > fromsource running as a Domain Controller in a small office. It's
> > being usedfor some basic AD functionality and sharing folders to a
> > half dozen Windowsdesktops on the local network and everything seems
> > to be running fine. I'dlike to modernize that setup with Ubuntu
> > 22.04 LTS running the latest andgreatest Samba 4.19.X from repo but
> > I'm not sure what the least terribleoption is in my case.
> >    - Backup and Upgrade Samba 4.1.0 to whatever the latest is that I
> > can on   CentOS 6.10, join the Ubuntu server as a DC with that Samba
> > same version,   demote/retire the CentOS server then upgrade Samba
> > on Ubuntu to the latest   and greatest?
> 
> This might work.  It would at least get you an in-place upgrade for
> some of the distance, but will be a pile of work and the server won't
> operate in the meantime, and you might just end up with no running
> server. 
> 
> >    - Backup CentOS Samba 4.1.0 files, setup Ubuntu server with Samba
> > 4.1   from repo, restore CentOS Samba 4.1.0 files to new Ubuntu
> > Samba 4.1.0   server and then upgrade to latest Samba? Basically
> > would be recovering it   there like a DR exercise with the Ubuntu
> > server having the same name, same   IP, etc?
> 
> This is difficult to get correct.  I wouldn't recommend it. 
> 
> >    - Create everything new on the Ubuntu server w/ a new Domain and
> > join   all the workstations there?
> 
> If this isn't a horrible process there are advantages to this, as all
> the changes Samba has made to the default domain will apply.
> 
> >    - Other less terrible options that could work?
> 
> Just install your new server, join and transfer roles.  There is a
> very good chance this will still 'just work'. 
> But regardless, for all options other than a rebuild, you will want to
> upgrade schema and functional level prep.  Lots of things to do once
> you upgrade, but upgrading is the best first step.
> Andrew Bartlett-- 
> Andrew Bartlett (he/him)       https://samba.org/~abartlet/
> Samba Team Member (since 2001) https://samba.org
> Samba Team Lead                https://catalyst.net.nz/services/samba
> Catalyst.Net Ltd
> 
> 
> Proudly developing Samba for Catalyst.Net Ltd - a Catalyst IT group
> company
> 
> Samba Development and Support: https://catalyst.net.nz/services/samba
> 
> Catalyst IT - Expert Open Source Solutions
> 
> 
> 

From what I can see, there is one DC running on Centos 6 with Samba
4.1.0, there are only 6 clients.

This is what I would do and it will probably be the quickest way:

Set up a new DC on Debian 12, using Samba from backports, this will get
you a very recent version of Samba.

Create your users and groups in the new AD Domain.

On the clients, leave the domain and then join the new domain.

Demote the old DC and then turn into a Unix domain member, sort out the
permissions on the data you have stored on it (I get the feeling that
you are using the old DC as a fileserver as well).

Create yet another Samba machine and join this as another DC (one DC is
a bad idea, two or more is good).

Any questions ?

Rowland