Prevent bounce on command time limit (feature request)
David Schweikert
Now and then we have procmail hitting command_time_limit. It happens
rarely (once a day or so), but when it happens, it is very bad because
the mail bounces. I am not sure why that happens actually: procmail has
TIMEOUT set, but sometime it just seems to hang. It might be a transient
problem with the operating system...
I don't want to set command_time_limit to 0, because if a user does
run a program in .forward that never terminates, we run out of local
processes.
Would it be possible to make the behaviour configurable, so that I could
tell Postfix to defer the mails instead of bouncing them?
I understand that we could then also run out of local processes, but in
our case, since it happens so rarely, it wouldn't be a problem (that's
why it should be configureable though).
Cheers
David
--
David Schweikert | phone: +41 44 632 7019
System manager ISG.EE | walk: ETH Zentrum, ETL F24.1
ETH Zurich, Switzerland | web: http://people.ee.ethz.ch/dws
Wietse Venema
> Hi,
>
> Now and then we have procmail hitting command_time_limit. It happens
> rarely (once a day or so), but when it happens, it is very bad because
> the mail bounces. I am not sure why that happens actually: procmail has
> TIMEOUT set, but sometime it just seems to hang. It might be a transient
> problem with the operating system...
>
> I don't want to set command_time_limit to 0, because if a user does
> run a program in .forward that never terminates, we run out of local
> processes.
This is a safety mechanism that prevents multiple instances of the
process piling up over each other.
If you want to disable the safety, then you can already do that be
setting a very large command_time_limit value. Postfix limits
the number of parallel delivery attempts per local recipient.
Mail that's stuck will still show up with mailq. And you probably
have to reboot the machine to get mail going again, so it hardly
matters if the mail is stuck in the active queue or in the deferred
queue.
I am very paranoid about turning off safety mechanisms in Postfix.
If it screws over someone's machine, then it will reflect badly on
Postfix's reputation.
Wietse
David Schweikert
On Fri, Jun 16, 2006 at 13:15:06 -0400, Wietse Venema wrote:
> This is a safety mechanism that prevents multiple instances of the
> process piling up over each other.
Ah, I understand. Suddenly you might also have multiple deliveries of
the same mail...
> If you want to disable the safety, then you can already do that be
> setting a very large command_time_limit value. Postfix limits
> the number of parallel delivery attempts per local recipient.
I didn't think about the per-recipient limit. Thanks, I'll do that.
> I am very paranoid about turning off safety mechanisms in Postfix.
> If it screws over someone's machine, then it will reflect badly on
> Postfix's reputation.
Yes, thanks for being paranoid :-) No wonder Postfix is so reliable...