[Samba] Questions on this upgrade scenario

[Andrew Bartlett]

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


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