[Samba] Unable to successfully join Samba 4.8.0 or Windows 2008 R2 to a Samba 4.6.7 DC, unable to upgrade in-place

[Andrew Bartlett]

On Sat, 2018-03-17 at 07:34 +1300, Andrew Bartlett via samba-technical
wrote:
> On Thu, 2018-03-15 at 16:10 -0400, Justin Foreman wrote:
> > Okay. The master build worked on the join. Excellent. So it was 4.8.0 having a problem. 
> > 
> > I’ve attempted to join 2008 R2 now to 4.8.0 but it still blue screens. Should I start a new thread for clarity’s sake?
> 
> So, I think this, the upgrade issues and even the old
> servicePrincipalName handling bug is all the same thing.
> 
> What happened is that in the past we did not reject:
> 
> servicePrincipalName: HOST/foo
> servicePrincipalName: host/foo

To further tie threads together, that would be:
https://bugzilla.samba.org/show_bug.cgi?id=8929

> Then with 4.8 the index code rejected this.  With master for 4.9 we
> decided it wasn't the index code's job to do this, so fixed that (it
> helped another use case). 
> 
> Add to this the upgrade code for GUID indexes didn't assert that if the
> re-index failed that we must abort the transaction, so the partial
> upgrade case gets committed and it all dies on the next DB open.
> 
> At least that is the theory I'll be working to prove or disprove on
> Monday.
> 
> I think the core short-term fix is in:
> 
> commit 5c1504b94d1417894176811f18c5d450de22cfd2
> Author: Gary Lockyer <gary at catalyst.net.nz>
> Date:   Wed Feb 28 11:47:22 2018 +1300
> 
>     ldb_tdb: Do not fail in GUID index mode if there is a duplicate
> attribute
>     
>     It is not the job of the index code to enforce this, but do give a
>     a warning given it has been detected.
>     
>     However, now that we do allow it, we must never return the same
>     object twice to the caller, so filter for it in
> ltdb_index_filter().
>     
>     The GUID list is sorted, which makes this cheap to handle,
> thankfully.
>     
>     Signed-off-by: Gary Lockyer <gary at catalyst.net.nz>
>     Reviewed-by: Douglas Bagnall <douglas.bagnall at catalyst.net.nz>
>     Reviewed-by: Andrew Bartlett <abartlet at samba.org>
> 
> 
> The replication to windows may be failing because of the duplicate
> value, eventually we will need to write a dbcheck rule to fix that.
> 
> Thanks all for your patience!
> 
> Andrew Bartlett
-- 
Andrew Bartlett                       http://samba.org/~abartlet/
Authentication Developer, Samba Team  http://samba.org
Samba Developer, Catalyst IT          http://catalyst.net.nz/services/samba