On 26.05.2010, at 21:01, Matt Hayes wrote: >> Is there >> something more I can do to mitigate the stress on the server? > > You could look into using RBLs such as spamhaus etc.
In general RBLs work fine against these dictionary attacks. But in this special case where not one address exists at the targeted domain, I doubt that RBLs would decrease server load, since that would add one more DNS lookup. I wouldn't see a big problem there, even thousands of 554s normally don't stress Postfix too much. Jan-Kaspar
