Hi, There are some destinations which refuse to talk to my server directly. My idea is to attempt deliver directly, and if it fails, attempt with fallback smtp server.
Looking at documentation, it seems that smtp_fallback_relay might be useful, but reading about it suggests that it won’t be helpful when there is 5xx errors. Here is an example of the error: relay=mxa-00018501.gslb.pphosted.com[208.86.201.80]:25, delay=50831, delays=50829/0.03/1.5/0, dsn=4.0.0, status=deferred (host mxa-00018501.gslb.pphosted.com[208.86.201.80] refused to talk to me: 554 Blocked - see https://ipcheck.proofpoint.com/?ip=xxx.xxx.xxx.xxx) What would be the best way to achieve my plan, when I don’t know ahead of time which destinations will be causing failures and I don’t want to relay through backup relay host all mail. Thanks, -sashk
