[Info-vax] TCPIP tying up system

[Jan-Erik Soderholm]

On 2010-11-30 20:35, Michael Moroney wrote:
> JF Mezei<jfmezei.spamnot at vaxination.ca>  writes:
>
>> Henry Crun wrote:
>
>>> RBLs: zen.spamhaus.org
>>> to cut out a lot of spam.
>
>> This cuts spam, but doesn't prevent the SMTP receiver from bogging the
>> system down to a halt for normal users.
>
>> By the time it gets to process the RBL, all the overhead from process
>> creation, running a .COM, activating the .EXE, having it read its
>> config, accept the TCP connection etc has been spent.
>
> Set the account priority of the TCPIP$SMTP account to something like 1 in
> the UAF, so that all "normal" processes always get priority.  The
> drawback is if you run compute-bound number crunchers the TCPIP$SMTP
> processes won't get CPU and legit email will get delayed or the links
> drop after timing out -->  very delayed or dropped emails.  But how
> many hobbyists run number crunchers on our VMS systems?
>
> BTW make sure your system is set up to not relay email (the default until
> recently was to relay).

Not that it matters much, but I have been configuring SMTP on a number
of TCPIP versions and never found RELAY as the default. This have
been most 5.x versions. Was you talking about older versions than
5.x ? It's not clear what "recently" is in your world... :-)

(In my case I needed RELAY to make the NBL ("No Blank Line") to work.


Jan-Erik.






   Perhaps the system is being attacked because
> spammers love to relay their spam through that system.