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Yes, you need a firewall on Linux - here's why and which to use
Out of the box, Linux is a highly secure operating system, but does that mean you can get by without a bit of help? Let's find out.
Some ne'er-do-well figures out what gateway you're using, breaks through its unpatched defenses, and has access to your network. Once enabled, all ports are closed, and accessing your machine is made exponentially more challenging. With a firewall active, your Linux machine will be better protected, should someone get around the defenses of your ISP's hardware.
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