Below is an Unix command to list all the IP addresses connected to your server on port 80. Output – Total connections by IP, from highest to lowest. Note This command is useful to detect if your server is under attack, and null route those IPs. Read this null route attacker IP story. Let break above lengthy command into pieces : 1. netstat -tn 2>/dev/null Uses netstat to list all network connections, ins and outs. -n – Display numeric only, don’t resolve into name. -t – Display only TCP connections. Output 2>/dev/null Redirect all unwanted output to /dev/null, a special place to absorb all output and clear it. 2. grep…