How does Linux use firewalls to block hacker attacks?
1) hackers use brute force cracking tools to remotely attack Linux servers through users
Name and password dictionary, attempt to log in to the Linux server operating system, as an operator
How can members stop hacker attacks?
2) remote login to the Linux server, and the Linux server opens the security log file:
/ var/log/secure records the login status of normal users or hackers, and analyzes the
File to find out the hacker's IP, and log in more than 10 times, add it to the Linux
Blacklist in Iptables Firewall
For i in $(grep "Failed password" / var/log/secure* | grep-oE
"([0-9] {1Magne 3}.) {3} [0-9] {1pr 3}" | sort-n | uniq-c | awk
'{if (($1 > = 10)) print $2}' | grep-v ^ 127); do iptables-I INPUT
4-s $I-j DROP;done
