Part 6: Security layer

30. Check the clock#

Why: logs, backups, updates and secure connections all depend on the right time. A wrong clock makes logs useless and can break updates. Time: 5 minutes.

Step 1: Switch on automatic time#

sudo timedatectl set-ntp true
sudo timedatectl set-timezone Europe/Paris
timedatectl

Use your own time zone. timedatectl list-timezones shows them all.

You want:

System clock synchronized: yes
              NTP service: active

It can take a minute to say yes.

Step 2: Only if it says "NTP not supported"#

There's no time service installed. Install the standard one and repeat step 1:

sudo apt install systemd-timesyncd

Next: 31. Fail2ban