> On Sep 18, 2017, at 12:59 PM, Andreas Thienemann <andr...@bawue.net> wrote:
>
>> * ONLY domains that contain no real recipients to be
>> handed off to some transport for delivery may be
>> listed in virtual_alias_domains.
>
> So just to confirm: virtual_alias_maps is also consulted for a match for
> addresses _not_ listed in virtual_alias_domains?
Virtual alias rewriting applies to *all* recipients, regardless of address
class.
>> Therefore you can have in virtual_alias_maps:
>>
>> # The dreaded catchall applies to all mailboxes that
>> # are not explicitly mapped to themselves or out of the
>> # domain
>> @real.example.com catc...@local.example.com
>> j...@real.example.com j...@real.example.com
>
> What does the mapping of the mailbox to itself do? I had not seen
> that before in the docs.
It avoids hitting the catch-all for that address. More specific
lookup keys preëmpt less-specific lookup keys, but keep in mind
that rewriting is recursive and stops only when:
* A lookup key maps to itself, OR
* A lookup key is not found, Or
* The recursion limit is reached
Otherwise, the RHS of a lookup becomes the LHS of the next lookup
up to the recursion limit.
>> and then in transport_maps:
>>
>> j...@real.example.com uucp
>>
>> or, conversely
>>
>> real.example.com uucp
>>
>> If the majority of users that stay in @real.example.comm use that
>> transport.
>
> During my testing the transport_maps entry seemed to not have been
> consulted, but then again I also did not have the j...@real.example.com
> mapping back to itself. Is that entry needed in such a form?
Transport selection happens downstream of virtual alias rewriting.
If the address rewrites to something else, transport lookup is
based on the final output of virtual alias rewriting.
--
Viktor.
