2018-01-02 update: With Crashplan version 6.6.0, remotely connecting to the Crashplan daemon running on a headless linux server stopped working. While it was never officially supported, it wasn’t outright broken until this update.
One (or the?) workaround is to use X11 forwarding to run the GUI application on the headless server and interact with the interface on a machine with an X server.
The GUI application is called
CrashPlanDesktop. In order to run it, you’ll likely
need to install some dependencies. Most – but not all – of them can be taken
care of by installing xterm (a terminal emulator for the X window system).
sudo apt install xterm
At this point, running
CrashPlanDesktop likely still won’t work. Any remaining
dependencies should be able to be addressed by iteratively attempting to run
from the command line, if nothing happens checking the UI error log located in
/usr/local/crashplan/log/ui_error.log, searching for the error to identify the
dependency, then trying again until it works.
One of the main dependencies of
CrashPlanDesktop that wasn’t pulled in by
libxss1, but there may be others.