How to immediately drop incoming and outgoing packets using Dynamic Firewall Manager

Enable panic mode to immediately drop incoming and outgoing packets using Dynamic Firewall Manager.

Query panic mode.

$ sudo firewall-cmd --query-panic

no

$ echo $?

1

Enable panic mode.

$ sudo firewall-cmd --panic-on

success

Query panic mode.

$ sudo firewall-cmd --query-panic

yes

$ echo $?

0

Disable panic mode.

$ sudo firewall-cmd --panic-off

success

Do not try this in a production environment as the access to the server will be cut-off.