Comprehensive and Detailed Explanation From Exact Extract:

The correct way to temporarily allow specific services in a particular zone with firewalld is to use firewall-cmd --add-service=service --zone=zone. Multiple services can be specified in curly braces and separated by commas. The correct syntax is:

bash

CopyEdit

firewall-cmd --add-service={dns,http,https} --zone=internal

This command will allow DNS (port 53), HTTP (port 80), and HTTPS (port 443) through the firewall for the 'internal' zone temporarily (for the current runtime session).

Other options:

A . The command syntax is incorrect; firewalld is a service, not a command-line tool.

B . iptables does not use the --enable-service flag, nor does it have zones in this way.

D . systemctl mask disables services, and the rest of the command is invalid.

CompTIA Linux+ Study Guide: Exam XK0-006, Sybex, Chapter 9: 'Networking', Section: 'Managing Firewalls with firewalld'

CompTIA Linux+ XK0-006 Objectives, Domain 2.0: Networking

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