On 1/19/06 11:21 AM, "Chris Knadle" <Chris.Knadle@???> wrote:
> On Thursday 19 January 2006 13:55, Tony Finch wrote:
>> On Thu, 19 Jan 2006, Chris Knadle wrote:
>>> Well, I just became a backup MX for an admin that is using Postfix
>>> that is making extensive use of these addresses with wildcards after the
>>> local_part.
>>
>> Do you mean something like local_part_suffix?
>
> Unfortunately I'm not sure what you mean, either. ;-)
>
> An example entry I would look to do would be:
> andy-*@???
> Which would match all of the following:
> andy-something@???
> andy-whatever@???
> etc.
>
>> Alternatively, you could just not bother to maintain a copy of the
>> userlist and use recipient callout verification instead.
>
> Yes, I did think of that, and it is a good suggestion. I haven't suggested
> that to the other admin yet, as I'm trying to avoid doing that as it
> generates more traffic and this admin is on a somewhat slow static DSL line.
I'm not sure recipient callout verification is really appropriate here.
Aside from spammers trying to sneak in (lots of activity), the reason a
message is presented to the backup MX is that the primary MX is unavailable.
It's likely still to be unavailable when the callout is done. So then you
generate a 4xx response, and the sender queues just as it would if there had
been no backup. (Exactly what I've seen Postini do with messages to an
unavailable (neighbor-to-us--lots of traffic) server to which Postini wants
to forward the message after testing it.)
It may well be better for there not to be a backup MX, unless the primary is
protecting against multi-day outages.
Of course, that may interfere with a business plan.
--John
Yahoo Groups behaves oddly with a 4xx response; I'm not sure what they do
with an unreachable MX.
