Re: [Exim] dnslookup failing for shortened domains

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Author: Christopher Chaduka
Date:  
To: Chip Coldwell
CC: exim-users
Subject: Re: [Exim] dnslookup failing for shortened domains
Try these options:

qualify_recipient and recipient_unqualified_hosts

HTH

Kiri

On Friday 02 January 2004 19:31, Chip Coldwell wrote:
> This is apropos exim v4.30 on Debian GNU/Linux, compiled from source.
>
> I've been having a problem with shortened addresses. Addresses such
> as "norcross@phys5", shortened from "norcross@???" are
> failing as unrouteable, even though "qualify_single" is set in the
> dnslookup router and "domain harvard.edu" is in /etc/resolv.conf. I
> traced the problem using "exim -d -bt norcross@phys5". I added a
> single line to host.c:host_find_bydns for debugging purposes:
>
> DEBUG(D_dns) debug_printf("DNS lookup qualify_single=%d
> search_parents=%d\n", qualify_single, search_parents);
>
> With this in place, here's the output of "exim -d -bt norcross@phys5":
>
>
> Considering norcross@phys5
>
> routing norcross@phys5
> --------> dnslookup router <--------
> local_part=norcross domain=phys5
> checking domains
> DNS lookup qualify_single=0 search_parents=0
> DNS lookup of phys5 (MX) gave HOST_NOT_FOUND
> returning DNS_NOMATCH
> phys5 in "@ : @mx_any"? no (end of list)
> phys5 in "! +local_domains"? yes (end of list)
> calling dnslookup router
> dnslookup router called for norcross@phys5
> domain = phys5
> DNS lookup qualify_single=1 search_parents=0
> DNS lookup of phys5-MX: using cached value DNS_NOMATCH
> dnslookup router declined for norcross@phys5
> "more" is false: skipping remaining routers
> no more routers
> norcross@phys5 is undeliverable:
> Unrouteable address
>
> What's happening is pretty clear: during evaluation of the router
> pre-conditions, host_find_bydns is called with qualify_single=0.
> Since "phys5" is not a top-level domain, this fails with
> HOST_NOT_FOUND, and the result is put in the cache, poisoning it for
> the later lookup with qualify_single=1.
>
> I consider this a bug.
>
> Chip


--

Christopher Chaduka
Technical Department
M-Web Zimbabwe (Pvt) Ltd
http://www.mweb.co.zw