[Courses] [courses][security] what logs?

[Hamster]

Hi!

While reading through various security related articles, and even some posts on our security course, I have seen numerous examples of people saying something like "I can see in our logs that we are getting scanned x times a day".

I feel a bit silly asking this, but what logs are they referring to?

Are these logs created by some separate programmes written specifically for monitoring portscans? (if so, what are some of these programmes called?)
OR
Are these logs created by iptables itself?


Ta :)

Hamster