Re: [Exim] name resolution with mailman and exim

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Author: Marc MERLIN
Date:  
To: Philip Hazel
CC: exim-users, precision
Subject: Re: [Exim] name resolution with mailman and exim
On Sat, Nov 04, 2000 at 05:47:36PM +0000, Philip Hazel wrote:
> > GI can tell exim not to verify the sender's address, but frankly, it doesn't
> > make a big difference compared to all the DNS queries that have to happen.
> > I'm guessing that by default, exim will have the same problem and hang until
> > each domain in rcpt to has been successfully resolved.
>
> Only if you set receiver_verify.


You are very correct, by default exim does the "right thing", perfect. (I
should know, I've been using exim for a while, but someone I got scared by
seeing loads of mailman mail not being delivered because of sendmail doing
DNS lookups on all the receipients at SMTP transaction time)

> > I could tell exim to just spool mail right away (i.e. do not attempt
> > immediate deliveries).
>
> You could, but that isn't relevant to whether it looks up the
> recipient's domains while receiving the message.


Considering the above, that makes sense.

> > That said, I'd much prefer another approach.
> > Is there a way to tell exim: process whatever you can do right away,
> > whatever resolves right now, and queue the rest?
>
> No, because that is exactly what it does all by itself when delivering a
> message.


Saw that too, perfect.

> You can tune the resolver timeouts in Exim:
>
> dns_retrans
>
>     Type:    time
>     Default: 0s

>
>     The options dns_retrans and dns_retry can be used to set the
>     retransmission and retry parameters for DNS lookups. Values of zero (the
>     defaults) leave the system default settings unchanged. The first value is

(...)

So if a query doesn't get any answer after dns_retrans x dns_retries seconds
(modulo what really happens in the resolver code), the mail gets spooled,
and exim tries again later, right?


Sorry for my initial Email, I should have known some of the answers already,
I got confused by seeing all the problems sendmail was causing in the
existing installation.

Thanks for your answers,
Marc
-- 
Microsoft is to operating systems & security ....
                                      .... what McDonalds is to gourmet cooking


Home page: http://marc.merlins.org/ | Finger marc_f@??? for PGP key