linuxexpert-practice-labs/labs/linux-plus/2-5-2-systemd-utilities/README.md

Linux+ 2.5.2: systemd tools

Setting the hostname and time zone, and changing a kernel parameter now and for good.

Before you start

The lab notes the hostname, time zone and vm.swappiness it finds, so that le-lab reset can put them back. If the time zone is already UTC, it sets it to America/Phoenix for now, and if vm.swappiness is already 20, it sets it to 60.

Tasks

1. Set the hostname to lab-alma.example.test (on an Ubuntu VM, lab-ubuntu.example.test is fine too), so that it stays after a reboot.
2. Set the time zone to UTC.
3. Set the kernel parameter vm.swappiness to 20 now, and in a file in /etc/sysctl.d/ so that it's 20 after a reboot too. (The chapter then removes the file again; leave it in place here.)

Hints

• hostnamectl, hostnamectl set-hostname, hostname.
• timedatectl list-timezones, timedatectl set-timezone.
• sysctl -n, sysctl -w, sysctl --system.
• The chapter's steps on resolvectl (Ubuntu) and systemd-analyze aren't graded; try them anyway.