You cannot force any other party to apply YOUR policy to THEIR systems. "Your server your rules, but my server my rules" :-) Furthermore mandatory tls can fail for a bunch of other reasons except from "not offering tls at all" ex no common cipher/tls version can be negotiated. I do mandatory tls on my servers too, but not globally. Just for selected rcpt-domains/next-hops
Cheers
tobi
Am 02.02.2018 um 09:36 schrieb Peter Keel:
Hi
I get these errors:
| TLS is required, but was not offered by host mx1.datacomm.ch[212.40.2.32]
and
| TLS is required, but was not offered by host relay.kfsb.ch[213.202.32.8]
Since I've made TLS for SMTP mandatory. The respective admins of these servers might want finally at least enable voluntary TLS; some of their customers apparently would like to receive mails from my server.
And by the way, RFC 2487 that is referred to for instance in the postfix manpage and stated that one must not make TLS mandatory has been obsoleted by RFC 3207.
Cheers Seegras