linux firewall (ufw or iptables) is used to restrict the client IP address range. It's best to restrict access to a limited network range . the firewall is a

linux firewall (ufw or iptables) is used to restrict the client IP address range. It's best to restrict access to a limited network range . the firewall is a kernel config. if configured properly no app can bypass A router that includes a firewall is a firewall. In my case the firewall was broken.