Flooded with emails to root -- URGG
david at vizion2000.net
Fri Sep 26 18:26:14 UTC 2008
On Thursday 25 September 2008 09:40:34 Chris Pratt wrote:
> On Sep 25, 2008, at 9:34 AM, David Southwell wrote:
> > Hi
> > I am running postfix.
> > Am receiving a flood of emails that appear to emanate from Servers
> > who have
> > received spam that has masqueraded root at mydomain as the email source.
> > Could anyone please suggest the best way of dealing with these.
> > Please bear in
> > mind I am not all that familiar with postfix so if anyone feels
> > treating me
> > like an idiot and spoonfeeding the actual command s to use I would
> > be most
> > appreciative <chuckles>
> I have no idea what a command would be to stop receipt. Cutting off the
> original generation of the emails being spoofed is more to the point.
> You may want to look at SPF (openspf.org). If your domain is listed
> with an
> spf entry in DNS, you become less tempting as a domain to spoof. Over
> time, it will all but cease. Once you've created an SPF DNS record, many
> servers receiving mail spoofed for your domain will begin to drop it
> than backscatter emails back to your server.
> You should study the information on their site but in a nutshell, you
> a TXT record in DNS that lists your servers IP as the only valid
> machine to
> send mail for your domain. This tells the others to drop emails from
> IPs using your domain. It's relatively effective and painless.
That really did the trick..
Within two hours the flood of backscatter (about 400 an hour) was virtually
That was great advice
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