Autor: John Dalbec Fecha: A: Tony Finch, Exim Users Mailing List Asunto: Re: [Exim] verify=sender/callout performance?
Tony Finch wrote: > "Alan J. Flavell" <flavell@???> wrote:
>
>>On Fri, 21 Mar 2003, John Dalbec wrote:
>>
>>
>>>The documentation mentions that verify=sender/callout is a
>>>performance hit.
>>
>>Sure - you've got to do practically all the work of setting up a
>>fresh mail transaction.
>
>
> Unless there's a cache hit.
>
>
>>And many an MTA will do no more than confirm an address as
>>syntactically correct, irrespective of whether it really exists,
>>which makes the callout a waste of time and effort.
>
>
> That's what verify = sender/callout,random is for.
Reading doc/NewStuff it's not clear whether the correct syntax is
"sender/callout,random" or "sender/callout=random". Exim seems to
accept both?
John
>
>
>>BTW, callout can also block mail from envelope senders whose mail
>>domain never responds.
>
>
> If you are inclined towards charity in this case then use
> verify = sender/callout,defer_ok
>
> Tony.
> --
> f.a.n.finch <dot@???> http://dotat.at/ > THE WASH TO NORTH FORELAND: EAST TO SOUTHEAST 3 OR 4. FAIR. MODERATE OR GOOD.
> SLIGHT.
>
> --
>
> ## List details at http://www.exim.org/mailman/listinfo/exim-users Exim details at http://www.exim.org/ ##
>
>
>