How to turn on your Linux firewall

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FirewallsMedium priority

About 5 minutes to complete

Switch on the firewall that comes with your system so unwanted incoming connections are blocked by default.

Step-by-step guide

On Ubuntu or Debian, open a terminal and run 'sudo ufw status'.
If it says inactive, run 'sudo ufw enable'.
On Fedora, run 'sudo firewall-cmd --state'; firewalld is usually on already.
You don't need to open any ports for normal desktop use.

4 steps

Why this matters

Most desktop Linux systems include a firewall that isn't enabled out of the box. Turning it on blocks unexpected connections to your machine.

How to confirm it worked

The setting is saved and active on your device
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