In practice this means it is possible to run Butler SOS, Butler Cache Warming etc as Docker containers on for example a Raspberry Pi 4. If you are worried about that poor little Raspi failing you can add a bunch of them into a Kubernetes cluster, and then run the Butler tools there.
This actually works pretty well, here is a Raspberry Pi based Kubernetes (a.k.a “k8s”) cluster built using the excellent k3s distribution, running the Butler tools:
And here is the Raspi cluster itself, with 4 of the 7 nodes installed:
Ok, ok – I hear you – is it really a good idea to run close to mission critical software on Raspberry Pi’s?
No of course not, but the cloud providers are starting to offer Arm based virtual machines (Amazon does this already with their EC2 A1 instances), with roughly twice the performance per dollar compared to Intel based VMs.
So running Butler on Arm VMs might be a way to save some money, if the cloud provider you use happens to offer Arm VMs.
Or just surrender to your inner geek and build your own Raspi k8s cluster… Lots of fun and a great way to learn about k8s!
Docker images available on Docker Hub, as always.