From: Wietse Venema (wietseporcupine.org)
Date: Sun Feb 03 2008 - 10:03:45 CST

• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

Ken D'Ambrosio:
> > Ken D'Ambrosio:
> >> Hi, all. I tried sending an e-mail to a domain, and got a bounce
> >> telling me that there was no associated MX record. I thought SMTP
> >> was supposed to
> >> failover and try the hostname, itself, no? Port 25 on the host is open,
> >> and seems to be accepting mail to users at that domain (I checked via
> >> telnet). Is there some parameter I'm missing somewhere to get Postfix
> >> to try this?
> >
> > Please show the complete error message.
> >
> > I use Postfix to send to non-MX destinations every day.
>
> [stock bounce stuff deleted]
>
> <zackzackbrown.com>: Host or domain name not found. Name service error for
> name=zackbrown.com type=MX: Host not found, try again

According to the RFC, the SMTP client MUST look up the A record IF
AND ONLY IF the MX record DOES NOT EXIST.

DOES NOT EXIST != TRYAGAIN.

        Wietse

• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]