Answers for "how to open ports on linux"

ports in use linux

# To see ports in use
sudo lsof -i -P -n | grep LISTEN 
sudo netstat -tulpn | grep LISTEN

check what ports are open linux

## if you use linux
sudo ss -tulw

used ports in linux

# To check the listening ports and applications on Linux
# Use any of the following command on terminal

sudo lsof -i -P -n | grep LISTEN 

sudo netstat -tulpn | grep LISTEN

sudo lsof -i:80 # see a specific port such as 80

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