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Installing FreeBSD V15.1 in a qemu virtual machine

Posted on 24/10/2026 | Leave a comment

Purpose.

The purpose of this how to is to provide some basic installation instructions to create a FreeBSD V15.1 system running xorg and a basic plasma configuration.

Create the Virtual disk.

qemu-img create -f qcow2 FreeBSD.img 20G

Initiate the VM.

qemu-system-x86_64 -machine q35 -accel kvm -cpu host -m 4096 -smp 2 -vga virtio --full-screen -nic bridge,br=virbr0,model=virtio-net-pci -device intel-hda -device hda-duplex -bios /usr/share/ovmf/x64/OVMF.fd --hda ~/FreeBSD.img --cdrom ~/Downloads/FreeBSD-15.1-RELEASE-amd64-disc1.iso

Start the installer.

I won’t go into the process for running the installer. Although it is a TUI, I find it quite intuitive to use. Just accept the defaults for now. Once the installer has finished perform a reboot ready for the first part of the configuration.

Basic System Configuration.

One the VM has rebooted and the FreeBSD login screen has been presented, login as the root user and run the following commands.

pkg
pkg install nano
pkg install xorg
freebsb-update fetch
freebsd-update install
reboot

The first command bootstraps the pkg installer and the following lines install the nano text editor and the xorg meta package. The last few commands do a binary update on the base system using the freebsd-update tool to fetch and install the updates. At the time of this post, there were over 500 updates and the system was patched to -p6. Finally reboot the VM to ensure the updates are all applied and your system is running all current versions. You will be back at the login screen. We will now move on to do some basic xorg configuration and install the required plasma desktop packages.

Create the basic xorg.conf files.

nano /usr/local/share/X11/xorg.conf.d/10-driver.conf

And add the following lines:

Section "Device"
 Identifier "Card0"
 Driver "scfb"
EndSection

nano /usr/local/share/X11/xorg.conf.d/30-keyboard.conf

And add the following lines:

Section "InputClass"
  Identifier "system-keyboard"
  MatchIsKeyboard "on"
  Option "XkbLayout" "gb,es"
  Option "XkbOptions" "grp:alt_shift_toggle"
EndSection

This will give the minimal config to test your xorg installation on FreeBSD V15.1. Now run the following command to ensure you get a GUI and test the keyboard layout to ensure it is correct.

startx /usr/local/bin/xterm

You should be rewarded with an xterm in the top right hand of the screen and then try entering your special keyboard characters to ensure they are being mapped correctly. Here’s a screen snip of mine. Apologies the size is rather small, just zoom in and you’ll see the characters. To exit xterm type exit press ctrl and d key at the same time. the x session will terminate and you’ll be back at the TUI.

Congratulations, you now have a basic working FreeBSD system with a GUI.

Installing plasma packages and a login manager.

We now move to the final steps in getting a working plasma installation running on your FreeBSD VM. Run the following commands to install plasma6-plasma and the sddm login manager.

pkg install plasma6-plasma sddm

This will install over 500 packages so I recommend you have another brew or do a minor house hold task to move those legs!

Once this has completed (hopefully successfully) there are a couple of system daemons to enable to ensure plasma will run correctly and that the sddm GUI login manager will be available as default.

sysrc dbus_enable=YES
sysrc sddm_enable=YES

The above commands enable the dbus process which is used heavily by plasma to shift messages between running components and the last command enables the sddm gui login manager. Once done reboot and you’ll be presented with the sddm login manager.

Plasma joy!

Happy computing.

We’re done for today. I hope this guide has been of some use to you.

Where next?

This was a quick run through a basic plasma installation. you might need some kde applications such as konsole, dolphin to make best use, just install them with the pkg command you are now used to.

For me, I am going to get some real bare metal to install this on a proper machine

Thanks for reading!

OpenBSD V8.0 on a qemu host

Posted on 23/10/2026 | Leave a comment

I’ve recently started to look at the *BSDs again. i have a love/hate repationship with FreeBSD which is now on a much more love basis as in the past a dirty shutdown would more often than not would lead to an fsck which screwed the whole system up. I’m not certain but I think they use a different filesystem now and it tends to be much more reliable even when it crashes in a desktop environment. Anyway, I wander as this is about OpenBSD but this issue will come back later!

So, first thing to do is to create a qcow2 filesystem

qemu-img create -f qcow2 OpenBSD.img 20G

with that created initiate the VM

qemu-system-x86_64 -machine q35 -accel kvm -cpu host -m 4096 -smp 2 -vga virtio --full-screen -nic bridge,br=virbr0,model=virtio-net-pci -device intel-hda -device hda-duplex -bios /usr/share/ovmf/x64/OVMF.fd --hda ~/OpenBSD.img --cdrom ~/Downloads/install80.iso

I am not going to walk you through the installer, it is pretty intuitive for a TUI. The only change I made was to do a custom disk layout by selecting a GPT disk and then adding a root (/) partition first then a swap partition for the remainder of the disk. If you accept the defaults, you will run out of space installing kde-plasma and other applications.

OK, with that done you now want to add a few applications. Login as root and use the pkg_add command to install a few favorites for me this is nano and a basic plasma install.

pkg_add nano kde-plasmsa

This will take a few minutes so go and make a brew! Once complete enable the messagebus daemon and reboot

rcctl enable messagebus
reboot

usermod -L kde myuser

Replace myuser with your regular user account.

Now, without a complete debrief which will bore the hell out of you (background here) plasma will not start correctly. loads of locale errors, file handler errors, plasmashell core dumps, black screen and general plasma hell will prevent your session from running. I did ask for help on the fediverse and a few people did give some good pointers which are incorporated in my post, especially this one as it verified the behaviour I was seeing and that’s normally a good thing as I wasn’t going mad! but it did not resolve the problem. Details at the end of this post or you’ll never forgive me for wandering again.

Now that your user is in the KDE login class, I still found the limits a bit on the low side so I increased the limits as shown below.

nano /etc/login.conf/kde
kde:\
        :datasize=8192M:\
        :openfiles-cur=2048:\
        :openfiles-max=2048:\
        :tc=default:

This should now give you sufficient file handles to run plasma. now on to the .xinitrc file.

The following .xinitc file was put together using the pkg-install readmes for DBUS and kde-plasma in the /usr/local/share/doc/pkg-readme directory

.xinitrc
export LC_CTYPE=en_GB.UTF-8
export XDG_RUNTIME_DIR=/tmp/run/$(id -u)
if [ ! -d $XDG_RUNTIME_DIR ]; then
    mkdir -m 700 -p $XDG_RUNTIME_DIR
fi

if [ -x /usr/local/bin/dbus-launch -a -z "${DBUS_SESSION_BUS_ADDRESS}" ]; then
    eval `dbus-launch --sh-syntax --exit-with-session`
fi
kscreen-doctor output.556.enable
/usr/local/bin/ck-launch-session /usr/local/bin/startplasma-x11 > plasmalog.txt 2>&1

without the kscreen-doctor line this is the cause of all the nightmares I had over 2 days working on this problem. The core reason the standard script doesn’t work is that for whatever reason plasma doesn’t enable the default output device (all those no screens found errors etc) The number varies by OpenSBD version, root V normal user, if vgaaperture setting is enabled in sysctl.conf. To find your magic number just startx without the .xinitrc file and you’ll default to TWM and run the following command

kscreen-doctor -o

and make a note for the .xinitrc file. Now you’re ready!

type startx and enjoy some wonderful plasam on OpenBSD on qemu!