Docker rootfs_linux.go permission denied when moun

Question

I'm using meteor-up to deploy to docker instances inside an LXD container. When it attempts to bring up a MongoDB docker instance, it fails with the following error:

docker: Error response from daemon: oci runtime error: container_linux.go:265: starting container process caused "process_linux.go:368: container init caused \"rootfs_linux.go:57: mounting \\\"proc\\\" to rootfs \\\"/var/lib/docker/vfs/dir/20a621a73755db3f4030bc67bbf7ff9540bd1d63bb348d8be440d8ca63d3c922\\\" at \\\"/proc\\\" caused \\\"permission denied\\\"\"".

I've tried deploying as the ubuntu user to my LXD container, and as root, and that hasn't helped. There's obviously some permissions issue here, but I don't know where to start debugging this problem.

Answer 1

According to https://discuss.linuxcontainers.org/t/having-trouble-using-docker/383 it sounds like you might need to set security.nesting=true. Stop the container (lxc stop deploy-container), configure nesting on (lxc config set deploy-container security.nesting true as per https://insights.ubuntu.com/2015/10/30/nested-containers-in-lxd) and lxc start deploy-container.