Basis ist Debian Trixie, in meinem Fall mit 6.18.x Kernel um die Netzwerkkarten meines Minisforum MS-S1 verwenden zu können:
<code>
benny@ailab:~$ sudo apt install qemu-kvm libvirt-daemon-system libvirt-clients \
  virt-manager bridge-utils virtinst
benny@ailab:~$ sudo usermod -aG libvirt,kvm $USER
benny@ailab:~$ sudo systemctl enable --now libvirtd
</code>

Aktuellste (stable) VM von der Release Page für KVM runterladen:
https://github.com/GNS3/gns3-gui/releases
<code>
benny@ailab:~/gns3$ wget https://github.com/GNS3/gns3-gui/releases/download/v2.2.59/GNS3.VM.KVM.2.2.59.zip
</code>

<code>
benny@ailab:~/gns3$ unzip GNS3.VM.KVM.2.2.59.zip
benny@ailab:~/gns3$ sudo cp *.qcow2 /var/lib/libvirt/images/
</code>

<code>
benny@ailab:~/gns3$ sudo nmcli con add type bridge ifname br0 con-name br0
benny@ailab:~/gns3$ sudo nmcli con add type bridge-slave ifname enp97s0 master br0 con-name br0-slave
benny@ailab:~/gns3$ sudo nmcli con modify br0 ipv4.method auto
benny@ailab:~/gns3$ sudo nmcli con modify br0 bridge.stp no
benny@ailab:~/gns3$ sudo nmcli show
benny@ailab:~/gns3$ sudo nmcli con show
benny@ailab:~/gns3$ sudo nmcli con down "Wired connection 1" 
benny@ailab:~/gns3$ nmcli con up br0-slave
benny@ailab:~/gns3$ nmcli con up br0
</code>

<code>
benny@ailab:~$ sudo virt-install   --name GNS3-VM   --memory 32768   --vcpus 16   --os-variant ubuntu24.04   --import   --disk path="/var/lib/libvirt/images/GNS3 VM-disk001.qcow2",format=qcow2,bus=virtio   --disk path="/var/lib/libvirt/images/GNS3 VM-disk002.qcow2",format=qcow2,bus=virtio   --network bridge=br0,model=virtio   --graphics vnc,listen=0.0.0.0   --video virtio   --noautoconsole

Starting install...
Creating domain...                                                                                                                            |         00:00:00     
Domain creation completed.
</code>

Alpine VM, da virtual PC kein brauchbares DHCP macht:
<code>
wget https://dl-cdn.alpinelinux.org/alpine/v3.24/releases/x86_64/alpine-virt-3.24.1-x86_64.iso
Template in GNS3 erzeugen
Alpine an Switchport hängen, starten und Console öffnen

root:<no password>

C: ip link set dev eth0 up
C: localhost:~# udhcpc -i eth0
udhcpc: started, v1.37.0
udhcpc: broadcasting discover
udhcpc: broadcasting select for 192.168.11.121, server 192.168.2.1
udhcpc: lease of 192.168.11.121 obtained from 192.168.2.1, lease time 6000
</code>