How secure is my trixbox Pro system?
This depends. If you have it protected behind a firewall than it should be fairly secure, however if you have ports like 22 for SSH open than it is still vulnerable to brute force password attacks. The best way to protect against this is to use very difficult to crack passwords. Do NOT use any dictionary word as this will virtually always end up in a hacked system. Use long passwords with a combination of upper and lower case, numbers, and symbols. So ‘password’ is probably a bad choice but My_HaRd-:Pazzw0rd345 would be much better.