> On Nov 27, 2019, at 1:35 PM, Wietse Venema <wie...@porcupine.org> wrote:
>
>> Would adding a new tenant to the system (i.e. a new route in Postfix)
>> require a restart, interrupting mail flow for existing tenants?
>
> Service disruption is unnecessary. "postfix reload" (not stop+start)
> should suffice.
When lists of relay, virtual, ... domains etc., are stored in tables
rather than listed verbatim in main.cf, even a reload is not generally
required, but may in some cases speed up the visibility of the new
data.
The main difficulty with multi-tenant configurations is hosting of
mailing lists (mailman and the like), this often requires per-tenant
user accounts which own the respective alias files, run maintenance
scripts, ...
If you're providing shared outbound mail, its "reputation" can be
tainted by just a single user who buys a list to market to, or
whose username/password is compromised.
--
Viktor.
