==== Required information ====
- iRedMail version (check /etc/iredmail-release):    0.9.6
- Linux/BSD distribution name and version:    Ubuntu 16.04.2
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):     MySQL
- Web server (Apache or Nginx):    Apache
- Manage mail accounts with iRedAdmin-Pro?    No
====

Hi,

I have iRedMail up and running well (thanks for the software!). Outgoing email goes via direct SMTP submission to the external destination server. All works fine over 99% of the time but, rarely, the user gets a blacklist bounce (generally because my IP on Dream Ocean is sharing an IP range with another user whose behavior is poor).

When my user tells me of the problem, I can engage with the destination server abuse admin but this takes time. I do have access to relaying via ISP and the setup instructions on http://www.iredmail.org/docs/relayhost.html works well.

However, I would prefer to first send emails directly (as it permits more control and I can be more sure I get error messages back) and then only automatically fallback to the ISP relayhost if this attempt fails.

Is this even possible?

Cheers,

Martin