I'm receiving error mails: couldn't reach your server; e-mail not sent. When I look at the Exim error logs, I see the host where I sent the mails from, followed by 'relay not permitted'. What can I do now?
You need to add the IP address of your host(s) to the list of the "permitted relayers".
Here is a simple article on how to configure that under Ubuntu, which has a split file type of configuration (as debian) and so differs from the official one.
update-exim4.conf.confto the IP address of the machine you want to relay from. Then you do the split config dance and run
update-exim4.confand you should now be able to relay email from that IP (or range of IPs).
After several hours of working in circles I stumbled upon the answer that worked for me. It didn't matter how many permutations of
dpkg-reconfigure exim4-config I tried, adding in entries for dc_relay_nets or dc_relay_domains or direct edits of exim4-local-domains.txt. It turns out there is a file named exim4-relay-mail-from-this-list-of-ip-addresses.txt in
/etc/exim4 that simply needs the ip address or CIDR block of the net you want to relay for (e.g. 18.104.22.168/24). Mine is set up with a single entry on each line, not a semicolon separated list like much else in exim4. A restart of exim4 was required in my case.
Now, with a name like that it would seem only a fool could miss something this obvious, but in all my internet searches this file name never once materialized and everything I read directs back to using
dpkg-reconfigure and working with dc_relay_nets. Hope this helps someone else avoid lost time.
I had the same problem. I found an answer to this question here:
the solution is to edit the file update-exim4.conf.conf as follows:
for "hostname" I entered the output of the command hostname, although I don't know if that is right. I also entered the relevant values for example1.com, and I was able to receive email when I sent it to firstname.lastname@example.org.