Hi, thank You for Your feedback.
Does this solution is also described by RFC ? I reviewed RFC but I see that SMTP loadbalancing should be done using DNS with proper setup MX records. With kind regards Zalezny On Fri, Nov 27, 2015 at 2:10 PM, Wietse Venema <wie...@porcupine.org> wrote: > Zalezny Niezalezny: > > Hi, > > > > I have a question regarding Domain MX record and physical SMTP > Loadbalancer. > > > > In my infrastructure we have several Postfix machines with local > mailboxes. > > Each system sending messages to relay servers using internal relay > domains > > with MX records. My team colleague told me that we will not use anymore > > local relay domains with MX records but Virtual host (with preconfigured > > relay systems behind) and F5 loadbalancer to transfer message from > Postfix > > servers to the relay hosts. > > > > I would like to know Your opinion about it ? I know that MX record has > been > > designed to avoid problems like E-mail loop etc.etc. Till now its working > > perfect for me. > > > > Does loadbalancer will not affect smtp communication ? > > The load balancer MUST provide Postfix with the remote SMTP client > IP address. Postfix has support for doing that with: > > - HAproxy protocol (uses the Postfix smtpd_upstream_proxy_protocol > and smtpd_upstream_proxy_timeout features). > > - nginx (uses the XCLIENT protocol). > > If your load balancer does not support one of the above protocols > then Postfix will not work properly, because all SMTP connections > will have the IP addres of the load balancer instead of the real > client. > > To prevent mailer loops, configure: > > /etc/postfix/main.cf: > proxy_interfaces = the loadbalancer external IP address(es) > > With these things taken care of, load balancers should work. > > Wietse >
