qemu-kvm und libvirt

libvirt

Running anything as root always has security implications and so has libvirt. Therefor make sure you have your user set in /etc/libvirt/qemu.conf:

which implies, that your virtual machines are accessable by the defined user and group as well. They usually live under /var/lib/libvirt/images when using libvirtd, where you can mount anything.

manually call qemu with kvm

You can use this script to start virtual machines manually and with many features enabled.

ich9-ehci-uhci.cfg
http://spice-space.org/
http://www.samba.org/

Read things like $(: enable usb2.0 support) as comment (bash does!)

Fixes

virsh does not start virutal machine with “Error: Machine ‘XYZ’ already exists”

This has been a bug, but in case your machine went into this trouble and you want to avoid a reboot, you can force the shutdown of the not-running process causing this issue by machinectl terminate qemu-xyz. The naming scheme differs slightly from the one we know from virsh and it can be looked up with machinectl list.

USB-Redirection not possible: Permission denied

That might be a polkit issue. I fixed it by creating a file:

max,