On 29 Jul 2019, at 0:56, Viktor Dukhovni wrote: > On Sun, Jul 28, 2019 at 08:14:38PM +0000, Bjoern A. Zeeb wrote: > >> Now sometimes the same email comes back to MX-E via an *alias* (no From: >> changes) on MX-3. MX-E will receive the looped back email from MX-3 >> and then decides by its transport rules that it should send it to MX-I. >> >> Here’s the problem: MX-E now tries to do SASL auth to MX-I for this >> looped back email and that fails. >> >> Is there any better (simpler) solution than to have a dedicated/split >> outgoing or incoming MX for this user? > > Use the "relay" transport for inbound traffic, and the "smtp" transport > only for outbound traffic. In the "relay" transport disable SASL auth: > > relay unix ... smtp > -o smtp_sasl_auth_enable=no
Thanks!
