KnowCardLinux · Firewalls (nftables & firewalld)
How do you dump the entire nftables ruleset, save it, and later restore it verbatim?
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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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Where does a Linux system map friendly names like ssh, http, and https to their numeric IP port numbers?
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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