In addition to hardening SSH access, we also need to restrict the ports that are allowed for communication in and outside the computer. We do so using the iptables service from Fedora. This is a program that monitors the access from other computers to our server and viceversa.
We need to enable ports for the following services
The second file is a twin of this one, /etc/sysconfig/ip6tables, and contains more or less the same
After editing these files and ensuring that they have the right permissions
we can restart the services
You can now check which ports are open by issuing
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