On Fri, Apr 08, 2011 at 11:44:12PM -0500, Noel Jones wrote:
> On 4/8/2011 11:29 PM, email builder wrote:
>>
>> Or is this of no concern and/or does the junk command limit take care of
>> it?
>
> If you have no use for ETRN just set
> smtpd_etrn_restrictions = reject
> or maybe better
> smtpd_etrn_restrictions = static:502
> and then forget about it.
>
> ETRN is not a particularly interesting attack/abuse vector with postfix.
> Don't spend much time worrying about it.
The most effective way to disable ETRN is to set:
# Empty disables ETRN and eliminates fast-flush cache overhead.
fast_flush_domains =
The default is:
fast_flush_domains = $relay_domains
You should then set "smtpd_etrn_restrictions = reject", but there is little
harm at that point in leaving it on.
--
Viktor.
