linux-bash-network.sh

linux bash network script port status

# https://www.binarytides.com/linux-ss-command/
# https://www.computerhope.com/unix/nc.htm

# show only the listening sockets (To get the output faster, use the "n" option to prevent ss from resolving ip addresses to hostnames)
ss -ltpn

ss -ltn

# test the connetion (netcat)
# "r" means report not connect

nc -rv <host> <port>

#### seee your own ip address
curl icanhazip.com

#### see your own ip address (filter out 127.x and 172. 
ifconfig | grep -Eo 'inet (addr:)?([0-9]*\.){3}[0-9]*' | grep -Eo '([0-9]*\.){3}[0-9]*' | grep -v '127.0.0.1'| grep -v '172.'

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https://www.cyberciti.biz/faq/unix-linux-check-if-port-is-in-use-command/

sudo lsof -i -P -n | grep LISTEN 
sudo netstat -tulpn | grep LISTEN
sudo nmap -sTU -O IP-address-Here