ubuntu server open port code example

Example 1: ubuntu open port

sudo ufw allow 1191/tcp

Example 2: see what is using a port ubuntu

$ sudo lsof -i:22

Example 3: open firewall port in linux

Debian: sudo ufw allow PORT. CentOS: sudo firewall-cmd --zone=public --permanent --add-port=PORT/tcp sudo firewall-cmd --reload

Example 4: ubuntu open all port

sudo ufw allow 1:9999/tcp