CompTIA Linux+ XK0-006 (V8) Practice Question

While preparing a CentOS Stream 9 DNS server you must open port 53 for both UDP and TCP traffic in the public zone. The change has to survive daemon reloads and system reboots, and you want the most maintainable one-line rule (that is, you prefer a predefined abstraction to listing individual ports). Which single command accomplishes this goal?

  • firewall-cmd --permanent --zone=public --add-port=53/udp

  • firewall-cmd --permanent --zone=public --add-service=dns

  • firewall-cmd --permanent --zone=public --add-port=53/tcp --add-port=53/udp

  • firewall-cmd --zone=public --add-service=dns

CompTIA Linux+ XK0-006 (V8)
Security
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