Linux · Firewalls (nftables & firewalld)

Debian ships no firewall and no firewall config tool of its own. So what does the Debian Wiki recommend you install?

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More in Firewalls (nftables & firewalld)

On a fresh openSUSE install the firewall is already blocking almost all outgoing traffic, and the built-in YaST firewall module is missing your Ethernet interface. What is the recommended way to fix rules?

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A colleague says every IP service confirms receipt of packets. Which common protocols contradict that, and why does it matter for firewall rules?

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