Re: [exim] 550-Relay not permited

On Mon, Nov 21, 2011 at 09:27:45AM +0000, K Z wrote:
> If i change the:
> dc_relay_domains=''
>
> to
> dc_relay_domains='*'
>
> in the update-exim4.conf.conf it allows the remote clients to send emails without the 550 relay error. But this ay it is a open relay and this i would like to avoid.
>
> I tried to:
> dc_relay_domains='example.com' but still does not work well.

It seems you are using the debian configurator. You will
probably get more apropos help on the debian forums. However I
will try to reply.

You need to explain what exactly you are trying to do. Most
mail servers do one or both of the following:

1) receive mail from anybody on the Internet for a list of
domains. These domains are usually local (local_domains /
dc_other_hostnames). Sometimes mail is relayed to other servers
(relay_to_domains / dc_relay_domains) but I don't think this is
your case. Local mail is mostly written to disk, in a place
where users can get it, usually with a POP/IMAP server.

2) receive mails from the users authorized to use the server,
and relay those mails to anyone on the Internet. You therefore
need to distinguish "your" users from "random spammers on
the Internet". The easy way for the administrator is to say
"my users are in network x.y.z.0/24". You'd put that in
relay_from_hosts (dc_relay_nets). If your authorized users have
fixed IP addresses, then that's perfect. Otherwise, you need
to force users to use a login and a password to send mail. Of
course this is more complicated! To do this, research "SASL".

Hope this helps you configure a spam-free server . . .