Hi all, I''m migrating a server from Gentoo to Debian and need a bit of help with the Debian split-config system. The server is a mail hub, so mail goes in and out on a number of different network interfaces, each with a different IP and hostname. By default the server''s hostname is sent as the HELO value on all interfaces, but the hostname only matches one of the IPs - on all the others the mismatch between IP and HELO value triggers various spam filters. Under Gentoo I had solved this by defining a different Exim remote_smtp transport for each IP and set the HELO value there, but as I am switching to Debian I would like to make use of the existing configuration system. However I can only see the REMOTE_SMTP_HELO_DATA variable which sets the HELO value globally, and REMOTE_SMTP_HELO_FROM_DNS which I can''t find any documentation for but doesn''t seem to do what I want anyway. I am using the hubbed_hosts file to configure routing rules (which mail domains are forwarded to which hosts) so this would be the ideal place to specify the HELO name to use for each connection, but it doesn''t look like there''s anything in place for this. Does anyone know if what I am trying to do is possible with the Debian Exim configuration system, or will I need to copy across the custom transports I was using under Gentoo? Many thanks, Adam.
Adam Nielsen <a.nielsen at shikadi.net> wrote:> I''m migrating a server from Gentoo to Debian and need a bit of help > with the Debian split-config system.> The server is a mail hub, so mail goes in and out on a number of > different network interfaces, each with a different IP and hostname. > By default the server''s hostname is sent as the HELO value on all > interfaces, but the hostname only matches one of the IPs - on all the > others the mismatch between IP and HELO value triggers various spam > filters.> Under Gentoo I had solved this by defining a different Exim > remote_smtp transport for each IP and set the HELO value there, but as > I am switching to Debian I would like to make use of the existing > configuration system. However I can only see the > REMOTE_SMTP_HELO_DATA variable which sets the HELO value globally, and > REMOTE_SMTP_HELO_FROM_DNS which I can''t find any documentation for but > doesn''t seem to do what I want anyway.> I am using the hubbed_hosts file to configure routing rules (which > mail domains are forwarded to which hosts) so this would be the ideal > place to specify the HELO name to use for each connection, but it > doesn''t look like there''s anything in place for this.> Does anyone know if what I am trying to do is possible with the Debian > Exim configuration system, or will I need to copy across the custom > transports I was using under Gentoo?As far as I see this is not possible with the default Debian Exim config system. But I also think you don''t need more than one custom transport. I use the following one for a setup quite like yours: remote_smtp: driver = smtp helo_data = ${lookup dnsdb{ptr=$sending_ip_address}{$value}{$primary_hostname}} This will set the HELO/EHLO value according the the hostname of the sending IP or to the primary_hostname, if the lookup fails. Gr??e, Sven. -- Sig lost. Core dumped.
>> The server is a mail hub, so mail goes in and out on a number of >> different network interfaces, each with a different IP and hostname. >> By default the server''s hostname is sent as the HELO value on all >> interfaces, but the hostname only matches one of the IPs - on all the >> others the mismatch between IP and HELO value triggers various spam >> filters. > > As far as I see this is not possible with the default Debian Exim config > system. > > But I also think you don''t need more than one custom transport. I use > the following one for a setup quite like yours: > > remote_smtp: > driver = smtp > helo_data = ${lookup dnsdb{ptr=$sending_ip_address}{$value}{$primary_hostname}} > > This will set the HELO/EHLO value according the the hostname of the > sending IP or to the primary_hostname, if the lookup fails.Ah interesting, thanks for your quick response! I think this is what REMOTE_SMTP_HELO_FROM_DNS does, but enabling it didn''t work for me and I now realise it was because it only seems to apply to the remote_smtp_smarthost transport, not remote_smtp. However I was able to avoid creating a custom transport by specifying your code in my main definition file as the global HELO override: REMOTE_SMTP_HELO_DATA = ${lookup dnsdb{ptr=$sending_ip_address}{$value}{$primary_hostname}} So far this seems to be working... I guess it would be worth extending REMOTE_SMTP_HELO_FROM_DNS to apply to all remote_smtp transports instead of just the smarthost one. Cheers, Adam.
On Sat, Jan 08, 2011 at 01:34:44PM +1000, Adam Nielsen wrote:> Under Gentoo I had solved this by defining a different Exim remote_smtp > transport for each IP and set the HELO value there, but as I am switching > to Debian I would like to make use of the existing configuration system.The existing configuration system is flexible. Just add your own remote_smtp transport or modify ours.> I am using the hubbed_hosts file to configure routing rules (which mail > domains are forwarded to which hosts) so this would be the ideal place to > specify the HELO name to use for each connection, but it doesn''t look > like there''s anything in place for this.And it''s hard to add at this place, since the file is route data which is handed verbatim to exim.> Does anyone know if what I am trying to do is possible with the Debian > Exim configuration system, or will I need to copy across the custom > transports I was using under Gentoo?Our configuration is rather not geared towards such advanced (and exotic) requirements. Feel free to use as much of our work that is helpful to you and modify it to your needs. This may be a case where the split config scheme may be helpful. But I''m biased here since I''m a big fan of the split configuratoin. Greetings Marc -- ----------------------------------------------------------------------------- Marc Haber | "I don''t trust Computers. They | Mailadresse im Header Mannheim, Germany | lose things." Winona Ryder | Fon: *49 621 72739834 Nordisch by Nature | How to make an American Quilt | Fax: *49 3221 2323190