How to install VirtualBox on Fedora?

The easiest is way is to install VirtualBox with RPM fusion repository:

1. Configure RPMfusion repository (as seen on http://rpmfusion.org/Configuration/):

   sudo dnf install https://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm https://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm

2. Install VirtualBox (as seen on http://rpmfusion.org/Howto/VirtualBox):

   sudo dnf install VirtualBox kernel-devel-$(uname -r) akmod-VirtualBox
   sudo akmods
   sudo systemctl restart systemd-modules-load.service

3. To verify whether VirtualBox is properly installed, command dmesg | grep -i vbox should return the following:

   vboxdrv: module verification failed: signature and/or required key missing – tainting kernel
   vboxdrv: Found 2 processor cores
   vboxdrv: fAsync=0 offMin=0x1c2 offMax=0xa5f
   vboxdrv: TSC mode is Synchronous, tentative frequency 3000795689 Hz
   vboxdrv: Successfully loaded version 5.0.6_ (interface 0x00240000)
   VBoxNetFlt: Successfully started.
   VBoxNetAdp: Successfully started.