On Thu, 12 Aug 2021 11:56:36 -0400, Matt Corallo stated: >On 8/12/21 09:37, Wietse Venema wrote: >> Matt Corallo: >>> I tried variations of this but never could get it to work - as far >>> as I could tell the nexthop is fully resolved by the time we get to >>> the smtp daemon, so there aren't any relevant settings to override >>> or otherwise set the default on the nexthop there. >> >> In the FILTER command you specify transport AND nexthop. There is >> nothing to be resolved BEFORE the SMTP client. > >Ah, thanks. Sadly I'm not sure this solves the immediate issue either >as it seems to override local domain delivery as well. i.e. it results >in any of the source addresses which would need proxying to external >domains being proxied to local domains as well. > >For context, this doesn't feel like a crazy setup - some users have >external addresses they want to be able to send mail as, which we >(obviously) need to relay via their external providers' smtp with >authentication. For local-domain mails, there are some providers >(*cough* Microsoft *cough*) which treat all mail from low-volume IPs >as spam, no matter what best-practices you comply with, so we want to >relay anything to Microsoft domains out via a third-party provider. > >Its currently working with a second postfix instance and a simple >socketmap program in transport_maps to lookup if a domain's MX is >*.outlook.com. > >Matt
Have you made any attempt to get your IP 'whitelisted' with Microsoft? -- Gerard
