On Tue, Sep 28, 2010 at 11:24:47AM -0500, Jason Voorhees wrote:
> I know that Postfix defaults virtual_alias_expansion_limit directive
> to 1000. I have a question:
>
> What happens if I have a virtual_alias_maps that returns more than
> 1000 results? Will postfix will send e-mail to the first 1000 results
> and ignore the rest from 1001?
What happens is that expansion stops, and any remaining addresses
remain unexpanded, and may generate bounces (if they are in a virtual
alias domain).
The behaviour when the limit is exceeded is not ideal. It is probably
better to reject the message. Wietse and I discussed this issue off-list
about a year ago, don't recall which, if either, of us was going to look
into it further...
Because recursive virtual expansion happens in the cleanup(8) server,
it is not possible to reject a single SMTP recipient that expands to a
list over the limit. Rather, the entire message would have to be rejected
after "." with a "queue-file write error" (and a more specific message
in the mail logs).
It is perhaps time to consider doing virtual expansion in the SMTP server
for a future Postfix 3.0 release. That would potentially allow wild-card
rewrites to co-exist with recipient validation.
> What's the postfix behaviour in this cases when a virtual_alias_maps
> returns more than 1000 (default) results?
>
> a) It causes a bounce to ALL results of the virtual_alias_maps?
No.
> b) It delivers the first 1000 then bounces the rest over the default limit?
Only the first 1000 undergo expansion, the others are not subjected to
virtual alias rewriting, and this may cause delivery to fail.
--
Viktor.
