Compress attachments

[Michael Menge]

Quoting Adam Tauno Williams <awilliam at whitemice.org>:

> On Mon, 2009-08-31 at 16:51 +0200, Paolo Cravero wrote:
>> andreas.moroder at sb-brixen.it wrote:
>> > Is it possible to configure cyrus the way that it compresses the
>> > attachments on the storage ( not for tranfer as in RFC 4978 ) ? I know
>> AFAIK there is no cyrus option to do this. Moreover cyrus does not separate
>> attachments from the message body, so the whole message would need to be
>> gzipped. For each and every message.
>> > that diskspace is cheap, but when you have to get back thousands of
>> > mailboxes from a backup, the smaller the files are the faster the
>> > restore is done.

IHMO the size does not matter that much, if you have many small files  
and a filebased backup, the metadata handling on restore will take a  
great percentage of the restore time and is independent of the size.

You need two different aproches for restore of few mailboxes
and disaster recovery. The first case can be done with any normal backuptool,
and delayed expung will take care of mails which arrived and where  
deleted bevor they where backuped. It also makes restoring of mails  
easy.

For desaster recovery you need somthing where you can acces a copy of  
the data,
or can stream the data back to disk. So you need an image based  
backup, snapshot or replication.

>
> Why not just compress the backup/restore stream?
>

IMHO the size of transfered data is not the problem.

>> Well, replicate live mailboxes data rather than rely on a single node and
>> frequent backups. :-) I'm also starting to love the delayed expunge facility
>> with respect to cheap disk space.
>
> I could never go back to living without delayed expunge;  a fabulous
> feature!

I don't want to miss it either


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