hostnamectl; # tested on 
   Static hostname: hpServerG6
  Operating System: Debian GNU/Linux 10 (buster)
            Kernel: Linux 4.19.0-12-amd64
      Architecture: x86-64

su - root;
apt update;
apt install qemu-kvm libvirt-clients libvirt-daemon-system bridge-utils virtinst libvirt-daemon virt-manager
usermod -a -G  libvirt user; # give user kvm privileges

now under MATE hit Alt+F2 and type “virt”

to bring up the virt manager gui (root is required)

also: always  go with the kvm native harddisk format (not vmware format, prone to trouble)

per default files of the vm are stored here

/etc/libvirt/qemu/vmname.xml; # config file
/var/log/libvirt/qemu/vmname.log; # log
/var/lib/libvirt/images/vmname.qcow2; # harddisk image

basic virsh commands

virsh nodeinfo; # info about the system
virsh list --all; # list all (running and off vms)

virsh start vmname; # start vmname
virsh reboot vmname; # reboot vmname
virsh shutdown vmname; # shutdown vmname
virsh destroy vmname; # forcefull poweroff vmname

virsh autostart vmname; # set vmname to autostart when host system starts
virsh autostart --disable vmname; # disable autostart for vmname

# shutdown all vms
for i in `sudo virsh list | grep running | awk '{print $2}'` do
    sudo virsh shutdown $i
done

# delete remove vmname (cleanly)
# including its storage columes
virsh destroy vmname 2> /dev/null
virsh undefine vmname
virsh pool-refresh default
virsh vol-delete --pool default vmname.qcow2


impressive: gpu pass through

kvm is used by many companies such as https://www.hetzner.com/

not many virtualization technologies can do that: https://dwaves.de/2017/12/23/kvm-gpu-graphic-card-pass-through-windows-games-on-linux/

Links & Credits:

https://www.linuxtechi.com/install-configure-kvm-debian-10-buster/ (thanks despite insane amount of ads) X-D (block this waste in Firefox with uBlock)

https://computingforgeeks.com/virsh-commands-cheatsheet/

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