I have 3 servers running CentOS 7.9. I never activated the ISPConfig built-in firewall, but decided to do so after the latest ISPConfig upgrade to 3.2.8p1. Strangely enough, on 2 out of the 3 servers the machines became unreachable after I run: bastille-firewall start When I stop the firewall the machines became accessible again. No other firewall is activated on these machines (from what I can tell). What am I doing wrong? Including below the output of iptables -n -L from each of the machines.