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Re: Lenny/exim4: how to set helo for outgoing SMTP



Kilian wrote:


Under etch, I just changed helo_data in /etc/exim4/exim4.conf.template
manually - not very nice, but it did what I needed. Now my mailconfig is
broken because some hosts won't accept my mails as the HELO does not
match the IP of the firewall, of course. Is there really no way to
change the outgoing HELO value in exim 4.69-9? I am using the "internet"
config of exim4.


My exim4 installation has:

- a HELO which can be resolved by public DNS i.e. has an A record
- a PTR record and an A record in public DNS which are complementary i.e. each points to the other

These are also the conditions which my exim4 looks for in incoming SMTP connections (in addition to a lot of country code and other filtering).

I agree with the other poster, that I'm using a single configuration file where HELO is set by primary_hostname in the first few lines of the main configuration section. This is exim4 4.63-17 on etch.

As it happens, the PTR-A pair for my IP address correspond to my subdomain at my ISP, and neither bear any relationship to any of the domains I actually use for email. I'm not aware of any email domain which refuses my email, though the only 'difficult' one I send to regularly is AOL.

It is alleged that there are some mail admins who require HELO and PTR to match, but to me that seems silly. While the specification for PTR records allows for multiple PTRs for one IP address, I think in practice there's little software which can deal with this. So anyone sending mail for multiple domains from one IP address will have unmatched PTR and HELO strings most of the time.

The difficult hurdle for the spammer in control of a home computer to jump is the PTR-A pair setup, as one must be set by the domain host and the other by the ISP. Neither are under user control.

--
Joe


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