Troubleshooting RVM Failed to Create the File on Debian
This Troubleshooting is usually Solving the “RVM Failed to Create the File Solution” Issue on Debian GNU/Linux.
At the same time this Tip is Solving also the Rvm “mkdir cannot create directory permission denied” Issue.

Fixing RVM Failed to Create the File
Setting Up Permissions Properly
Allow Write Permission of All the Users of the “rvm” Group to the Target Folder with:sudo chmod -R 770 /usr/local/rvm