Running Docker inside runcvm

[jimaek]

I was wondering if you have advice on what is necessary to make docker run properly inside runcvm.

I am using the standard FROM ubuntu:22.04 image but docker always fails to start

INFO[2024-04-16T18:55:31.377862594Z] containerd successfully booted in 0.028850s  
ERRO[2024-04-16T18:55:31.401038646Z] failed to mount overlay: no such device       storage-driver=overlay2
ERRO[2024-04-16T18:55:31.401552453Z] exec: "fuse-overlayfs": executable file not found in $PATH  storage-driver=fuse-overlayfs
INFO[2024-04-16T18:55:31.404625332Z] Loading containers: start.                   
WARN[2024-04-16T18:55:31.405617629Z] Running modprobe bridge br_netfilter failed with message: , error: exec: "modprobe": executable file not found in $PATH 
INFO[2024-04-16T18:55:31.408205404Z] unable to detect if iptables supports xlock: 'iptables --wait -L -n': `iptables/1.8.7 Failed to initialize nft: Protocol not supported`  error="exit status 1"
INFO[2024-04-16T18:55:31.432359836Z] stopping event stream following graceful shutdown  error="<nil>" module=libcontainerd namespace=moby
INFO[2024-04-16T18:55:31.432619588Z] stopping healthcheck following graceful shutdown  module=libcontainerd
INFO[2024-04-16T18:55:31.432675019Z] stopping event stream following graceful shutdown  error="context canceled" module=libcontainerd namespace=plugins.moby
failed to start daemon: Error initializing network controller: error obtaining controller instance: failed to create NAT chain DOCKER: iptables failed: iptables -t nat -N DOCKER: iptables/1.8.7 Failed to initialize nft: Protocol not supported

Since you already have a small mention of running Docker inside the VM, maybe you could expand on it a bit to better understand how to get it fully operational?

The end goal is to use runcvm to run github runners inside, which in turn run docker containers as part of CI workflows. Full dockerfile https://github.com/jimaek/github-runner-dockerfile

Thanks!