Set Up UFW firewall on Debian 10

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sudo apt update
sudo apt install ufw

sudo ufw status verbose

Status: inactive

To configure your UFW firewall to accept SSH connections, run the following command:

sudo ufw allow OpenSSH

to allow some port...

sudo ufw allow 7722/tcp

to Enable UFW:

sudo ufw enable

to view enabled ports

sudo ufw status numbered

to delete

sudo ufw delete xxx

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