Install the D-Bus bridge
USBGuardGUI reaches the USBGuard daemon only through its D-Bus bridge, usbguard-dbus, which owns
the name org.usbguard1 on the system bus. usbguard-gui --diagnose tells two situations apart:
- not installed — nothing owns the name and nothing can: the package is missing;
- not running — the bridge is installed but its service is stopped.
If it is not installed
Where the bridge lives depends on the distribution:
| Distribution | Package | Command |
|---|---|---|
| Fedora, RHEL, CentOS | usbguard-dbus (separate) |
sudo dnf install usbguard-dbus |
| Debian, Ubuntu | inside usbguard |
sudo apt install usbguard |
| Arch | inside usbguard |
sudo pacman -S usbguard |
If it is not running
If --diagnose also reports that usbguard.service is not active, the daemon itself is stopped.
Before starting it for the first time, read the warning in the
Quickstart: a daemon started with an empty
policy blocks every USB device, keyboard included.
Check
The Bridge (org.usbguard1) line should read running, and the result connected.