[Samba] Upgrading Samba AD without upgrading any DC

[Rowland Penny]

On Fri, 7 Feb 2025 17:05:59 +0000
Stephen Brandli via samba <samba at lists.samba.org> wrote:

> HI,
> 
> Really appreciate you guys!
> 
> Three questions:
> 
> First, I am installing new DCs using Bookworm's stable install.

That would get you Samba 4.17.12, but using bookworm-backports will get
you 4.21.3 ( the latest version ).

>  The
> current DCs are running Bullseye (again using i's latest).  I don't
> think upgrading a DC directly will be easy if I have to do it.

I upgraded Raspberry pi bullseye to Raspberry pi bookworm and it worked

>  (They
> run in containers on a Buster host.)

You really need to upgrade the host as well, buster LTS went EOL over
six months ago.

>  Is it feasible/advisable to
> upgrade by installing a couple of new DCs, joining them to the
> domain, and then retiring the older servers?

You can do that, but it raises the RID pools.

>  Or, would it be best
> that I install a DC on a Bullseye server that can be upgraded, join
> the domain, and then upgrade that?
> 

You could do that, but use bookworm and skip the upgrading.

> Second, if things go wrong, can a backup of a Bullseye DC be
> installed on a new Bookworm DC?  What type of backup would you
> recommend?
> 

I cannot recommend doing a backup of a DC, backing up the domain with
samba-tool is okay, but only use such a backup if you suffer a
catastrophic failure of all DCS.

Rowland