Virtuakube sets up virtual Kubernetes clusters for testing.
It has several advantages compared to minikube or cloud clusters:
- Support any number of nodes, limited only by system RAM.
- Can run without root privileges (sort of - currently still requires docker privileges for image building).
- Can run without internet access.
- Because it emulates a full ethernet LAN, can be used to test networked systems.
- After initial setup, can recreate a complex VM and network topology in <10s, ideal for running lots of unit tests.
It's a very young system, and is being built for the needs of testing MetalLB, but seems like it could be generally useful for both playing with Kubernetes and testing scenarios. However, as of now you should expect the API to change frequently. Users and contributions are welcome, but be aware you're using a very young piece of software.
Your host machine must have
The CLI under
cmd/vkube is a quick way to get started. All resources
in virtuakube live in a
Universe. Within a universe there are three
Images are base disk images for VMs,
VMs are machines
that can talk to each other and the internet, and
Kubernetes clusters bootstrapped on VMs.
First, let's create a universe and build a VM base image inside it:
vkube newimage --universe ./my-test-universe --name base
This will create the
my-test-universe directory to store universe
state, and build a VM base disk that contains Kubernetes tools and
prepulled control plane images. Building the image takes about 5
Once we've done that, we can run a cluster in our universe:
vkube newcluster --universe ./my-test-universe --name example --image base
Bootstrapping a cluster takes a couple of minutes, but when done vkube will print something like:
Created cluster "example" Done (took 1m32s). Resources available: Cluster "example": export KUBECONFIG="/home/dave/my-test-universe/cluster/example/kubeconfig" VM "example-controller": ssh -p50000 root@localhost VM "example-node1": ssh -p50003 root@localhost Hit ctrl+C to shut down
From there you can use the cluster as you wish, or SSH into VMs to do
more stuff. The VMs created here are ephemeral, so when you ctrl+C
they will be deleted, and you'll have to run
newcluster again to
If you want to suspend and resume your cluster instead of
creating/deleting, just add
--save to the commandline. With
--save, all running VMs will be snapshotted to disk, and will all
resume as if nothing happened the next time the universe is opened. To
open a universe and resume whatever was saved, but without creating
new resources, use the
vkube resume --universe ./my-test-universe
Assuming you created and saved a cluster previously, you'll get familiar output:
Done (took 791ms). Resources available: Cluster "example": export KUBECONFIG="/home/dave/my-test-universe/cluster/example/kubeconfig" VM "example-controller": ssh -p50000 root@localhost VM "example-node1": ssh -p50003 root@localhost Hit ctrl+C to shut down
The cluster is back, but this time it took less than a second to come up (your mileage may vary, depending on disk and CPU performance - but it should be much faster than creating VMs from scratch).
All vkube commands accept
--save to mean "resume from the current
state next time, instead of reverting to the last savepoint. Saving is
off by default for all commands except
newimage (which is why the
base image we created stuck around - vkube implicitly saved the
universe after creating the image).
All vkube commands accept
--wait is true, vkube will
pause after the requested command has executed, print the available
resources (as above), and wait for ctrl+C before closing the universe
(with or without saving, depending on
--save). Waiting is on by
default for all commands except
So, if you wanted to non-interactively create a universe, build a base image, build a cluster and then immediately save it for future use, you'd run:
vkube newimage --universe ./my-new-universe --name base vkube newcluster --universe ./my-new-universe --name example --image base --save --wait=false
Then, later, play with your cluster:
vkube resume --universe ./my-new-universe