On Debian Buster I have installed the UFW Firewall
However, after enabling
$ ufw enable
Command may disrupt existing ssh connections. Proceed with operation (y|n)? y
Firewall is active and enabled on system startup
The Firewall is disabled after Reboot
$ ufw status
Status: inactive
The Config-File looks like this:
nano /etc/ufw/ufw.conf
ENABLED=yes
Help is very appreachiated!
You need to enable the service with a service manager.
sudo systemctl start ufw # starts the service
sudo systemctl enable ufw # starts the service on boot
ufw enable should do the same. See the first Output:
Firewall is active and enabled on system startup
However, your suggestion:
$ sudo systemctl enable ufw
Synchronizing state of ufw.service with SysV service script with /lib/systemd/systemd-
sysv-install.
Executing: /lib/systemd/systemd-sysv-install enable ufw
Has no effect:
$ ufw status
Status: inactive