[CentOS] Large scale Postfix/Cyrus email system for 100, 000+ users

Tue Oct 23 17:51:04 UTC 2007
mouss <mlist.only at free.fr>

Matt Shields wrote:
> On 10/23/07, mouss <mlist.only at free.fr> wrote:
>> There are primarily two ways:
>>
>> [virtual aliase]
>> you can use virtual_alias_maps to redirect foo at example.com to
>> foo at hostN.example.com, provided the final server accepts such addresses.
>>
>> If the final server doesn't accept these, and you use smtp to relay to,
>> then you can write the addresses back, using smtp_generic_maps.
>>
>> [transport]
>> an laternative is to use use (per-user) transport_maps. something like
>>
>> foo at example.com         relay:[hostN.example.com]
>>
>>
>> In bothe approaches, the mappings can be generated using sql statements
>> (mostly CONCAT). something like
>> ...
>> query = SELECT concat('relay:[', host, '.example.com]')
>>         FROM User
>>         where '%u' = user and '%d' = domain
>>
>> you get the idea I hope.
>>
>>
>>
>>> Anyone have a working example that they could share?  It would be
>>> greatly appreciated.
>>>
> 
> Forward's aren't acceptable. 

That's why I said to use smtp_generic_maps. This way, the "forward" is
internal. This is more efficient that transport_maps.

> There is a way to do it with the
> transport function and lmtp on a account by account basis.  I'm
> looking for real world configs from someone that has this working.

sorry, I don't. anyway, I see you got about the same answer from Wietse
and Viktor on the postfix list.