If you go thru sour code: "smtp/smtp_connect.c", it will merge both destinations in transport and multiple destinations in smtp_fallback_relay, then try these destinations one by one. If destination is MX record format (without square bracket), it will query all DNS MX record and try them one by one. So MX format can support multiple destination in workaround, however such support depends on DNS server. If we add such support by adding several codes in "smtp/smtp_connect.c", I think it's more convenient for user to set different destinations. That's why I want to add such patch to current Postfix source code.
2013/7/15 Wietse Venema <wie...@porcupine.org> > King Cao: > > Currently Postfix doesn't support multiple destinations on transport > (eg: > > smtp: [192.168.0.1]:25, [192.168.0.2]:10025 this is not supported). > > However Postfix support multiple destination on smtp_fallback_relay (eg: > > smtp_fallback_relay = [192.168.0.1]:25, [192.168.0.2]:10025). > > Now I have implemented this feature(support multiple destinations) > based > > on Postfix 2.8.8 (it's easy to add it on latest version). > > My question is who can I contact with to check whether/how I add my > patch > > on source code tree. > > Wietse: > > Use smtp_fallback_relay. > > King Cao: > > I know smtp_fallback_relay can support multiple destinations, however, > > this setting is for all domains. If I want to set different multiple > > destinations for different domains/sub domains, the only workaround is to > > use MX query (without square bracket[]), but such workaround can't set > > different port for different destinations. That's why I want to add some > > patch to support multiple destinations for transport (also support > > different port). > > Multiple destinations per nexthop would break queue manager's > concurrency scheduling policies or it would would break the queue > manager's independence of nexthop syntax. > > I am suspicious about applications that require manual configuration > of different fallback routes for different destinations. If you > really need such things then you can use different transports, each > having their own smtp_fallback_relay, smtp_bind_address and so on. > > Wietse >
