Blacklisting IPs and my 3CX domain

[biggreyphone]

Fairly new user. I am using a 3CX hosted system and have started to get hit with what appears [to me] to be a large number of hackers. I changed the ban time to 1 year for fun. My question is this, my 3CX server domain name is fairly random. Out of curiosity I wanted to know, how are these hackers finding my domain to try to hack into in the first place?

 

[cobaltit]

They aren't. There's scripts that scan blocks of IP addresses for common service ports. Then record them and then swing back by using specific tools against whatever open ports are found.

 

[ChrisC_3CX]

Just as a side note, you might also want to check that the Global IP Blacklist is enabled under "Security >> Antihacking" to help mitigate the problem.