Re: [exim] Exim as a backup MX server

On 07/04/2020 19:43, Linda Pagillo via Exim-users wrote:
> set up Exim as a backup MX server for the
> Windows servers.

Preferably you need to have the backup know what the legitimate
email accounts are - both local-part and domain - so that it
can reject bad ones at SMTP time. Otherwise it becomes a source
of backscatter (and, while I think of it, please do ensure that
your primary does the same. It's not the default Exchange
configuration; they do accept-then bounce as standard).

Getting that knowlege depends on your existing setup.
Possibly it's a case of pointing Exim at your AD server,
and hoping it really does talk LDAP sanely.
--
Cheers,
Jeremy