Hi,
Our public IP address has been blacklisted several times by CBL. I want to be aware of listing and want to setup a probe for this.
I know there are two ways to check if a certain address is blacklisted. Let assume that our IP address is 1.2.3.4. The first way to determine if the address is listed is by pinging 4.3.2.1.cbl.abusenet.org. If it replies, the address is blacklisted.
The second way is to do a reverse DNS lookup. If 4.3.2.1.cbl.abusenet.org can be resolved, the address is blacklisted.
This is where my knowledge stops. How can I turn either one of both ways into a probe?
Regards,
Jasper Kimmel