Upgrade 2.2 -> 2.4

[Anthony Prades]

On 03/29/2011 09:25 PM, Henrique de Moraes Holschuh wrote:
> On Tue, 29 Mar 2011, Ondřej Surý wrote:
>> I have just tested the upgrade from 2.2 to 2.4 on my server and it's
>> still quite complicated even when the spool is empty :-(.
>>
>> We need to work on that since almost all cyrus-*-2.2 packages were
>> left in the Install/Conf-files state and purging them removed some
>> files from -2.4 packages.
>>
>> I'll try to do more serious testing, but it seems that we will need to
>> upgrade scripts in 2.2 as well.
>
> Actually, I think we have some outstanding nastyness in 2.2 with
> security implications that deserves a look as well, but I have not found
> time to work on that at all.  It is all in the BTS.
>
> It is possible to use preinst to safeguard against installing without the
> unfixed 2.2 packages, and avoiding data loss is a damn good reason to do
> that.  OTOH, if all that happens is a broken package that --reinstall
> can fix, we can probably document that in {NEWS,README}.Debian, plus the
> upgrading docs.
>

Hi,

during my personal test, I wrote preinst script to backup all Cyrus 
databases into "/var/backup". This is available there: 
https://github.com/toony/pkg-cyrus-imapd-2.4-toony/tree/debian-sid-upgrade

I can commit this as a starting point.

In all cases, I think that backuping before upgrade is a "damn good 
reason" too.

Anthony