Autor: martin.dm.hull Data: A: exim-users Assumpte: [exim] problems with host authentication (no IP address found for
host ...)
Hi
After upgrading our outgoing mail servers from exim 3.6 to exim 4.5, a
lot of customers are unable to send mail. There appears to be a major
difference in how host authentication is done.
Previously, exim3 took the IP address of sending host, did a reverse
lookup to get a host name and looked for a match in a file. If the
customer domain was example.com, there would be 2 lines in the file for
example.com and *.example.com. This worked well.
Not so in exim4! Some of our customers have dodgy DNS. So after getting
the host name, instead of looking for a match in the file, exim4 instead
goes and does a forward lookup on the host name and comes back with
NXDOMAIN. Exim4 reports that it couldn't find the hostname.
Now I know it would be great if our customers had their DNS correct but
that will take a long time to get them sorted, so how do I make it work
like exim3?
On a domain basis, I can add '+include_unknown' which works. However
'accept hosts = +include_unknown:+relay_hosts' does not.
