[Dovecot] LMTP SIZE Option

[Robert Schetterer]

Am 24.06.2010 11:08, schrieb Luca Corti:
> On Thu, 2010-06-24 at 09:40 +0200, Robert Schetterer wrote: 
>>  Hi Timo, if overquota bounce with dovecot2 lmtp was asked here
>> this allready works , tested it with postfix combi
> 
> I guess SIZE optimizes the process. You can reject *before* DATA, at
> RCPT TO stage.
> 
> ciao
> 
> Luca
> 
yes of course it would ,but tried
to write a postfix policy server which does like this
but its extrem ugly, i stopped it ,and know now why its not allready done
by others, the main probelem is that you never know the real size
of a mail until its fully got ( or late got , and there many other
problems too i.e can i trust the client about size he gave etc), but
with dove2 lmtp
and postfix  asks dove2 lmtp in smtp income stage about quota so mail
can be bounced overquota before the con is finished what means
the main problem i.e thinkable backscatter cause by overquota is fixed
that way. ( behave that i tested, hopefully right)
alternate you can use postfix with the vda patch ( not remommended by
orginal developers of postfix ) , dont looked in their patch how solved
the quota problem, but if you use it ,you will loose filtering with
sieve done by lda or lmtp , cause it delivers directly to maildir,
other soltuion ( smtp proxy milter etc ) may always ask th quota by
backplained real mailservers smtp process,
so for now to me it looks like dove2 with lmtp ist the best solution you
can get at the moment , or write yourself a policy daemon etc
finally the theme is that complex that i might fail here with tec
details, but this is my current knowledge, perhaps some others
have better ideas/knowledge recently

-- 
Best Regards

MfG Robert Schetterer

Germany/Munich/Bavaria