Knowledge Base
To check for open TCP ports using nmap:
$ sudo nmap -sT -p- 10.10.8.8
To check for open UDP ports using nmap:
$ sudo nmap -sU -p- 10.10.8.8
Not sure if this even works:
for PORT in {20..80}; do timeout 1 bash -c "/dev/null" && echo "port $PORT is open" ; done
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