the base

Keep the system up to date. Unattended upgrades is not new debian but more often used by ubuntu users. But from time to time you need the system check done by hand. Security leaks by misconfiguration or baseconfig update is not fixed by unattended upgrades!

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the user

No need to operate as root. Root can do

rm -Rf /*

the user can't - try it - you will do it only once! Second argument is that the most common attack brute force vector tries first to access as root. Disallow ssh root access combined with iptables ( ufw ) and fail2ban saves you a lot of headaches.

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the kick in

The most important part of base setup is the reconfiguration of the sshd. Restrict the ssh login and turn on the firewall. After installing fail2ban we've build a good base for headless OS.

ATTENTION - before you restrict the ssh daemon you need to login as user [ m0r4k ] and try [ sudo su ]. If this doesn't work you won't get su privileges anymore and you are locked out as superuser!

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