samba - Mar 2021 - samba 4.9.7 - DC online backup error - "uncaught exception - 'TarFile' object has no attribute '__exit__'"

Hello Andrew,

Thank you for your input. I really appreciate getting suggestions and advice
from such a prominent Samba veteran!

According to your thoughts my plan will be to start to join a new DC (DC3) to
the domain and then try to do an online backup on the new DC. Hopefully this
will work better.

If all work out well I plan to transfer the FSMO rules to DC3 (from the current
holder DC1). Is there certain steps I need to take before or after the transfer
of the FSMO rules? Do I need to change DNS entries etc? I suppose I need to
change the rsync based Sysvol replication (which I have set up according to
https://wiki.samba.org/index.php/Rsync_based_SysVol_replication_workaround) to
replicate from DC3 to DC1 (instead from DC1 to other DC:s as is now the case).

Thanks again and best regards,

Carlos

________________________________
From: Andrew Bartlett <abartlet at samba.org>
Sent: Friday, March 19, 2021 7:12 PM
To: Carlos Gardel <carlosito2021 at outlook.com>; samba at lists.samba.org
<samba at lists.samba.org>
Subject: Re: [Samba] samba 4.9.7 - DC online backup error - "uncaught
exception - 'TarFile' object has no attribute '__exit__'"

On Thu, 2021-03-18 at 19:27 +0000, Carlos Gardel via samba
wrote:
> Hi,
>
> I've been running two DC:s (DC1 and DC2) in a pure samba AD domain
> since 2015 on Centos 6. Starting with version 4.1.14 I have upgraded
> my way to version 4.9.7. It seems I have now reached the limit for
> possible upgrades of these DC:s since it is no longer possible to
> upgrade to 4.10 on Centos 6.
>
> I'm now preparing to deploy a DC3 on a Centos 8 vm with samba 4.14.0.
> Before joining it to the domain I have tried to make an online backup
> of the AD on the two existing DC:s following the guide at
> https://wiki.samba.org/index.php/Back_up_and_Restoring_a_Samba_AD_DC.
>
> When I run the command (as root) "samba-tool domain backup online --
> targetdir=/root/samba-backup/ --server=DC2 -UAdministrator" I get the
> following error:
> I would be very grateful for all the help I can get since it would
> feel fantastic to be able to perform a backup before I start to join
> new DC:s and make changes to the existing setup.
The backup is taken over the network, so just start he backup on a new
modern Samba version, rather than with the old one.

Python 2.6 was poorly tested with Samba - every release we would have a
bug filed about some issue or other - which is one of the reasons we
raised the minimum version recently to 3.5 and 3.6 - it was becoming
foolish to pretend to support versions that we didn't run CI on.

Andrew Bartlett
> Best regards,
> Carlos
>
--
Andrew Bartlett (he/him)       https://samba.org/~abartlet/
Samba Team Member (since 2001) https://samba.org
Samba Team Lead, Catalyst IT   https://catalyst.net.nz/services/samba

Samba Development and Support, Catalyst IT - Expert Open Source
Solutions

On Wed, 2021-03-24 at 12:33 +0000, Carlos Gardel via samba
wrote:
> Hello Andrew,
> 
> Thank you for your input. I really appreciate getting suggestions and
> advice from such a prominent Samba veteran!
No worries.
> According to your thoughts my plan will be to start to join a new DC
> (DC3) to the domain and then try to do an online backup on the new
> DC. Hopefully this will work better.
You can do the backup, before you join, on any server with modern Samba
installed, it need not be the new DC3, but could be.  The point of the
backup tool is that it does not modify the domain.  It also allows you
to know that most likely the join will work beforehand.

Andrew Bartlett

-- 
Andrew Bartlett (he/him)       https://samba.org/~abartlet/
Samba Team Member (since 2001) https://samba.org
Samba Team Lead, Catalyst IT   https://catalyst.net.nz/services/samba

Samba Development and Support, Catalyst IT - Expert Open Source
Solutions