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+---
+layout: post
+title: Windows VM under Devuan with QEMU / libvirt
+date: 2021-03-23 20:32 +0100
+categories: tech
+---
+So, I'm running Devuan Beowulf (Debian Buster based). Recently, I was in the need of running a
+tax software which only supports Windows (also has a web-based solution, which is okay, but I prefer
+to keep my data local).
+
+I started running the software with Wine 5. A system upgrade to Wine 6 broke the software. I managed to downgrade
+wine, however, the software was really running flaky and unreliably from that on.
+
+So I convinced myself to run a Windows VM. VirtualBox is "too easy", also, there seem to be performance issues.
+Also, I wanted to learn something, so I dove into the libvirt/qemu/KVM stack.
+
+Boy, did I lose some hair over this.
+
+[With](https://linuxhint.com/libvirt_qemu_kvm_debian/) [some](https://www.florian-fritsch.com/kvm-unter-debian-10-mit-windows-10-vm/)
+[help](https://dennisnotes.com/note/20180614-ubuntu-18.04-qemu-setup/) from the internet, I managed to get a Windows machine running.
+
+From what I figured out, I need the following packages. I don't remember what apt installed as recommended/suggested packages
+anymore, though.
+
+- virt-manager: GUI for managing VMs
+- gir1.2-spice-client-gtk-3.0: Needed for viewing the VM
+- spice-vdagent: Desktop integration (copy/paste, auto-resize)
+- dnsmasq: Needed for NAT networking (daemon can be disabled)
+- libguestfs-tools: Command line tools for managing disk images
+- qemu-kvm qemu: Actual virtualization software
+- virt-viewer: Additional tool for viewing guest, has additional feature of folder sharing (?)
+- libvirt-daemon libvirt-daemon-system: Virtualization daemon. Calls QEMU? (also supports LXC and others)
+- libvirt-clients: Command line tool to manage VMs
+- ovmf: For UEFI support
+
+A word about ovmf: I created the VM before installing it. Once the VM is created, it's not possible
+to change the firmware from BIOS to UEFI. So better install it first.
+
+So
+
+```
+# apt install virt-manager gir1.2-spice-client-gtk-3.0 spice-vdagent dnsmasq libguestfs-tools qemu-kvm qemu virt-viewer libvirt-daemon libvirt-daemon-system libvirt-clients ovmf
+```
+
+Next, there was a suggestion to add a libvirt group - or libvirtd, whatever you prefer (which Devuan doesn't seem to do automatically).
+Next, add your user to the group.
+
+```
+# groupadd --system libvirt
+# gpasswd -a <username> libvirt
+# gpasswd -a <username> libvirt-qemu
+```
+
+Next, there are some config file changes to do.
+
+First, edit `/etc/libvirt/libvirtd.conf`. Search for the respective settings.
+
+```
+unix_sock_group = "libvirt"
+unix_sock_rw_perms = "0770"
+```
+
+Then, edit `/etc/libvirt/qemu.conf`. 
+
+```
+user = "libvirt-qemu"
+group = "libvirt-qemu"
+
+nvram = [
+   "/usr/share/OVMF/OVMF_CODE.fd:/usr/share/OVMF/OVMF_VARS.fd"
+]
+# Important! You need to remove all other default entries, even if they
+# are comments. The config parser seems to have problems with comments
+# inside the array. So this won't work:
+#  nvram = [
+#     "/usr/share/OVMF/OVMF_CODE.fd:/usr/share/OVMF/OVMF_VARS.fd"
+#  # other....
+#  # entries...
+#  ]
+```
+
+You might also want to copy `/etc/libvirt/libvirt.conf` to `$HOME/.config/libvirt/` and adjust the
+default connection URL, so virsh on command line will use the system qemu connection.
+
+```
+# $HOME/.config/libvirt/libvirt.conf
+uri_default = "qemu:///system"
+```
+
+After these changes, you must restart the libvirtd daemon. Also, logout and login so you're member
+of the correct groups. You're better off with restarting the system probably.
+
+Finally, you can create a VM with virt-manager, which I won't detail in here. Look at the other guides ;)
+
+However, I should mention I had severe problems with virt-manager complaining about
+insufficient permissions for the disk image when creating the VM, although it was owned by the
+libvirt-qemu group, which I was a member of.
+
+I ended up creating the VM as root, which is less than ideal. Somehow the image
+ended up being owned by root:root, although, from my understanding, it should've been created
+for the group libvirt-qemu. Input is welcome.