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It's possible to run Hedgehog Fabric in a fully virtual environment using QEMU/KVM and SONiC Virtual Switch (VS). It's a great way to try out Fabric and learn about its looka and feel, API, capabilities and etc. It's not suitable for any data plane or performance testing as well as not for production use.

In the VLAB all switches will start as an empty VMs with only ONiE image on them and will go through the whole discovery, boot and installation process like on the real hardware.


The hhfab CLI provides a special command vlab to manage the virtual labs. It allows to run set of virtual machines to simulate the Fabric infrastructure including control node, switches, test servers and automatically runs installer to get Fabric up and running.

You can find more information about getting hhfab in the download section.

System Requirements

Currently, it's only tested on Ubuntu 22.04 LTS, but should work on any Linux distribution with QEMU/KVM support and fairly up-to-date packages.

Following packages needs to be installed: qemu-kvm swtpm-tools tpm2-tools socat and docker will be required to login into OCI registry.

By default, VLAB topology is Spine-Leaf with 2 spines, 2 MCLAG leafs and 1 non-MCLAG leaf. Optionally, you can choose to run default Collapsed Core topology using --fabric-mode collapsed-core (or -m collapsed-core) flag which only conisists of 2 switches.

You can calculate the system requirements based on the allocated resources to the VMs using the following table:

Device vCPU RAM Disk
Control Node 6 6GB 100GB
Test Server 2 768MB 10GB
Switch 4 5GB 50GB

Which gives approximately the following requirements for the default topologies:

  • Spine-Leaf: 38 vCPUs, 36352 MB, 410 GB disk
  • Collapsed Core: 22 vCPUs, 19456 MB, 240 GB disk

Usually, non of the VMs will reach 100% utilization of the allocated resources, but as a rule of thumb you should make sure that you have at least allocated RAM and disk space for all VMs.

NVMe SSD for VM disks is highly recommended.

Installing prerequisites

On Ubuntu 22.04 LTS you can install all required packages using the following commands:

curl -fsSL -o
sudo sh
sudo usermod -aG docker $USER
newgrp docker
sudo apt install -y qemu-kvm swtpm-tools tpm2-tools socat
sudo usermod -aG kvm $USER
newgrp kvm

Good output of the kvm-ok command should look like this:

ubuntu@docs:~$ kvm-ok
INFO: /dev/kvm exists
KVM acceleration can be used

Next steps

Last update: January 22, 2024
Created: December 22, 2023