Every now and then, there comes a time when you need to make DNSqueries more complicated than gethostbyname and gethostbyaddr . Orat least, that's what happens to me.

When this happens, my best Python tool is the dnspython module , a pure Python modulefor doing all sorts of DNS manipulation. But dnspython is alittle bit obscure to use, so here's a sample program.

This program looks up IP addresses on the command line that are in the SBL and reports the URLs to their SBL

There's a spam storm blowing strong this week and it's irritating me,because it's pretty much all coming from compromised zombiemachines. Again. Zombies are clearly the number one general spamproblem, and it's probably only going to get worse as more and more ofthe world gets more and more broadband.

The biggest indicator I have of the storm is simple: since 6am onSunday, we've had 233,000 SMTP connections. As mentioned recently,

In this context, 'ASN' stands for 'Autonomous System Number' ;broadly speaking, this tells us who is responsible for a particular IPaddress (or, technically speaking, who is ultimately responsible forgetting IP packets to it).

There's a number of who other ways to tell who owns an IP address(querying whois.arin.net and then other registrars, for example), butthere are two attractions of ASNs for this purpose:

• there are comprehensive IP to ASN databases that are easily