Qubes specific VM config files

These files are placed in /rw, which survives a VM restart. That way, they can be used to customize a single VM instead of all VMs based on the same template. The scripts here all run as root.

  • /rw/config/rc.local - script runs at VM startup. Good place to change some service settings, replace config files with its copy stored in /rw/config, etc. Example usage:

    # Store bluetooth keys in /rw to keep them across VM restarts
    rm -rf /var/lib/bluetooth 
    ln -s /rw/config/var-lib-bluetooth /var/lib/bluetooth
    
  • /rw/config/qubes-ip-change-hook - script runs in NetVM after every external IP change and on “hardware” link status change.

  • /rw/config/qubes-firewall-user-script - script runs in ProxyVM/AppVM with qvm-features <vmname> qubes-firewall true after each firewall update. Good place to write own custom firewall rules.

  • /rw/config/suspend-module-blacklist - list of modules (one per line) to be unloaded before system goes to sleep. The file is used only in a VM with PCI devices attached. Intended for use with problematic device drivers.

Note that scripts need to be executable (chmod +x) to be used.

Also, take a look at bind-dirs for instructions on how to easily modify arbitrary system files in an AppVM and have those changes persist.

GUI and audio configuration in dom0

The GUI configuration file /etc/qubes/guid.conf in one of a few not managed by qubes-prefs or the Qubes Manager tool. Sample config (included in default installation):

# Sample configuration file for Qubes GUI daemon
#  For syntax go http://www.hyperrealm.com/libconfig/libconfig_manual.html

global: {
  # default values
  #allow_fullscreen = false;
  #allow_utf8_titles = false;
  #secure_copy_sequence = "Ctrl-Shift-c";
  #secure_paste_sequence = "Ctrl-Shift-v";
  #windows_count_limit = 500;
  #audio_low_latency = false;
};

# most of setting can be set per-VM basis

VM: {
  work: {
    #allow_utf8_titles = true;
  };
  video-vm: {
    #allow_fullscreen = true;
  };
};

Currently supported settings:

  • allow_fullscreen - allow VM to request its windows to go fullscreen (without any colorful frame).

    Note: Regardless of this setting, you can always put a window into fullscreen mode in Xfce4 using the trusted window manager by right-clicking on a window’s title bar and selecting “Fullscreen”. This functionality should still be considered safe, since a VM window still can’t voluntarily enter fullscreen mode. The user must select this option from the trusted window manager in dom0. To exit fullscreen mode from here, press alt + space to bring up the title bar menu again, then select “Leave Fullscreen”.

  • allow_utf8_titles - allow the use of UTF-8 in window titles; otherwise, non-ASCII characters are replaced by an underscore.

  • secure_copy_sequence and secure_paste_sequence - key sequences used to trigger secure copy and paste.

  • windows_count_limit - limit on concurrent windows.

  • audio_low_latency - force low-latency audio mode (about 40ms compared to 200-500ms by default). Note that this will cause much higher CPU usage in dom0.