Marc Perkel wrote:
>
> Chris Lightfoot wrote:
>> On Mon, Nov 13, 2006 at 09:53:30PM +0000, Stephen Gran wrote:
>>
>>> On Mon, Nov 13, 2006 at 01:39:47PM -0800, Marc Perkel said:
>>>
>>>> Is there a way to do a time based conditional in an ACL? Like I want to
>>>> do something different for one minute out of every 5?
>>>>
>>> Yes, use modulo on a time operator.
>>>
>> probably easier to do a regex match on $tod_zulu, for
>> instance,
>>
>> ${if match{$tod_zulu}{[05]Z\$}{ ... }fail}
>>
>> or similar.
>>
>>
>
> Thanks Chris - that works. What I want to do is basically leave message
> in the logs of hosts with bad reverse lookup with the hope that they
> will fix it. Here's my code.
>
> defer message = DEFER - Your REVERSE DNS is broken on IP
> $sender_host_address Please FIX IT!
> condition = ${if eq{$sender_host_name}{}}
> condition = ${if match{$tod_zulu}{[05]Z\$}{yes}{no}}
>
>
> The idea here is I return a temp error 1 in 5 times. Not enough to block
> them. But enough to maybe get people's attention when they look at their
> logs. Hopefully someone will notice it and fix it.
>
> I recommend that everyone do this and if they did it would improve
> things in general.
>
If you do at least a host -v, dig, or whois on a sampling of those arrivals, you
will probably find yourself trying to modify the behaviour of zombified WinBoxen
on dynamic IP.
Hardly likely to 'improve things in general' - unless you own stock in the local
power grid.
Bill
