Spam and sieve vacation

[Jorey Bump]

Janne Peltonen wrote:
> On Fri, Aug 24, 2007 at 07:47:28AM -0400, Jorey Bump wrote:
> 
>> If you don't get much spam, sieve vacation is suitable.
> 
> But how much is much, in your opinion? Say, 4 spam messages per day per user,
> with 50 000 users? Would that be much? If, during summer, 25% of our
> users were to have vacation active at any given time, that'd result in
> 50 000 vacation spams per day...

In my opinion, no amount of backscatter is acceptable, so I don't allow 
user-configurable autoresponders or forwarding. My antispam measures 
have reduced the amount that makes it to the user's inbox to about 
5/week, so I will make a rare exception, but only if I configure it 
myself. Forwarding has proven to be more risky than autoresponses, 
because agressive ESPs can create a temporary DoS to their sites for the 
entire server. This is particularly frustrating when the cause is your 
own user marking a forwarded message as spam.

On systems that I use but don't manage, autoresponders and forwarding do 
cause problems, and servers get publicly blacklisted regularly. There is 
also an increase in volume caused by the backscatter from autoresponses, 
affecting both bandwidth and storage needs.

That said, both features can be useful and even justifiable, but have 
fallen into disfavor due to the problems they cause. RFC 3834 compliance 
and continual evaluation of your antispam measures will help. 
Unfortunately, demand for these features often has a political component 
that can affect you professionally, so only you can decide what's best.