Clear Linux Installer v2.0
22 Apr, 2016
Robert A. Nesius
Early versions of Clear Linux on Intel Architecture* images had only a single-purpose hard install: to install the OS as host. The installer would destroy all data on /dev/sda without warning. Since there was no UI to choose from, users needed a dedicated system or an entirely separate hard drive to install and test.
However, we've recently improved the experience for our users with a graphical installer option. This is the second-generation graphical installer and we're excited about the enhancements. The design guidelines that inspired this UI were based on two concepts: the "principle of least surprise" and "inspiring confidence".
Least Surprise
Jef Raskin, who started the Macintosh project at Apple Computer in 1979, explores the principle of least surprise along with the concept of cognetics -- ergonomics for the mind -- in his book entitled The Humane Interface. With Raskin's thoughts in mind, our goal with Clear Linux installer is to present an experience that is familiar, comfortable, and free of surprises.
Our first "it works but it's not pretty" graphical installer had a lot of rough edges. For example, the keyboard arrow keys were the only way to navigate the user interface, and there was no way to revisit a previous screen to reconsider a configuration choice.
Now, tab keys move the focus -- as is customary in any modern GUI -- and pressing the enter key also moves the focus out of the text edit boxes. Nearly every screen may be revisited if the user wishes to reconsider their choices. The user interface on each installer screen is stateful; when revisiting screens, all previous configuration choices are preserved.
Other features and highlights of the installer include:
Telemetry Opt-In Screen
One of the first changes a user will see is an opt-in screen for our Telemetry feature. Before Clear Linux had an interactive installer, Telemetry was enabled by default. But now that we do actually have an Installer UI, users can make a choice. Now the defaults are set such that the user must take action to opt-in to sharing anonymous quality-related data.
Partitioning and Filesystems
Configuring disks and filesystems is a very common activity related to OS installation. Our 1st-gen installer only supported installing onto a device in a destructive fashion - all previous disk configuration and filesystems were lost. The new installer allows the user to configure the disk from within the installation workflow, and to map filesystems to partitions as well.
Better options when "Things go wrong"
For various reasons, an install might fail. When failures occurred, the 1st-gen graphical user interface stranded the user at a dialog box without further information or options to explore what went wrong. The installer now allows users to view installer logs, drop into a command line, or restart - all from within the UI.
While we know there are still some opportunities for functional and usability improvements, we're happy with this version of the installer. Feedback and ideas for changes are always welcome - please don't hesitate to share ideas on the project mailing list.