From ae388d0edb43a49a1fb86fc92adbd4449f3b6cd1 Mon Sep 17 00:00:00 2001
From: Priya Wadhwa <priyawadhwa@google.com>
Date: Wed, 22 Apr 2020 14:10:16 -0700
Subject: [PATCH] Add --force-systemd flag to force container runtime to use
 systemd

---
 cmd/minikube/cmd/start_flags.go     |  2 ++
 pkg/minikube/cruntime/containerd.go |  5 +++++
 pkg/minikube/cruntime/crio.go       |  5 +++++
 pkg/minikube/cruntime/cruntime.go   |  2 ++
 pkg/minikube/cruntime/docker.go     | 23 +++++++++++++++++++++++
 5 files changed, 37 insertions(+)

diff --git a/cmd/minikube/cmd/start_flags.go b/cmd/minikube/cmd/start_flags.go
index c735e8025d..af42ee7c59 100644
--- a/cmd/minikube/cmd/start_flags.go
+++ b/cmd/minikube/cmd/start_flags.go
@@ -98,6 +98,7 @@ const (
 	nodes                   = "nodes"
 	preload                 = "preload"
 	deleteOnFailure         = "delete-on-failure"
+	forceSystemd            = "force-systemd"
 )
 
 // initMinikubeFlags includes commandline flags for minikube.
@@ -135,6 +136,7 @@ func initMinikubeFlags() {
 	startCmd.Flags().IntP(nodes, "n", 1, "The number of nodes to spin up. Defaults to 1.")
 	startCmd.Flags().Bool(preload, true, "If set, download tarball of preloaded images if available to improve start time. Defaults to true.")
 	startCmd.Flags().Bool(deleteOnFailure, false, "If set, delete the current cluster if start fails and try again. Defaults to false.")
+	startCmd.Flags().Bool(forceSystemd, false, "If set, force the container runtime to use sytemd as cgroup manager. Currently avaiable for docker and crio. Defaults to false.")
 }
 
 // initKubernetesFlags inits the commandline flags for kubernetes related options
diff --git a/pkg/minikube/cruntime/containerd.go b/pkg/minikube/cruntime/containerd.go
index 73261c9819..570407b61a 100644
--- a/pkg/minikube/cruntime/containerd.go
+++ b/pkg/minikube/cruntime/containerd.go
@@ -429,3 +429,8 @@ func addRepoTagToImageName(imgName string) string {
 	} // else it already has repo name dont add anything
 	return imgName
 }
+
+// TODO: Implement for containerd
+func (r *Containerd) ForceSystemd() error {
+	return nil
+}
diff --git a/pkg/minikube/cruntime/crio.go b/pkg/minikube/cruntime/crio.go
index 250d765df4..4ff52cc37e 100644
--- a/pkg/minikube/cruntime/crio.go
+++ b/pkg/minikube/cruntime/crio.go
@@ -229,3 +229,8 @@ func (r *CRIO) Preload(cfg config.KubernetesConfig) error {
 	}
 	return fmt.Errorf("not yet implemented for %s", r.Name())
 }
+
+// ForceSystemd does nothing for crio since it already uses systemd as cgroup manager
+func (r *CRIO) ForceSystemd() error {
+	return nil
+}
diff --git a/pkg/minikube/cruntime/cruntime.go b/pkg/minikube/cruntime/cruntime.go
index f1866ff1aa..3a5ad43d89 100644
--- a/pkg/minikube/cruntime/cruntime.go
+++ b/pkg/minikube/cruntime/cruntime.go
@@ -104,6 +104,8 @@ type Manager interface {
 	SystemLogCmd(int) string
 	// Preload preloads the container runtime with k8s images
 	Preload(config.KubernetesConfig) error
+	// ForceSystemd forces the container runtime to use systemd as cgroup manager
+	ForceSystemd() error
 }
 
 // Config is runtime configuration
diff --git a/pkg/minikube/cruntime/docker.go b/pkg/minikube/cruntime/docker.go
index eb11b58e83..eb4c8030df 100644
--- a/pkg/minikube/cruntime/docker.go
+++ b/pkg/minikube/cruntime/docker.go
@@ -25,6 +25,7 @@ import (
 
 	"github.com/golang/glog"
 	"github.com/pkg/errors"
+	"github.com/spf13/viper"
 	"k8s.io/minikube/pkg/minikube/assets"
 	"k8s.io/minikube/pkg/minikube/bootstrapper/images"
 	"k8s.io/minikube/pkg/minikube/command"
@@ -110,6 +111,10 @@ func (r *Docker) Enable(disOthers bool) error {
 		}
 	}
 
+	if err := r.ForceSystemd(); err != nil {
+		return errors.Wrap(err, "forcing systemd")
+	}
+
 	return r.Init.Start("docker")
 }
 
@@ -274,6 +279,24 @@ func (r *Docker) SystemLogCmd(len int) string {
 	return fmt.Sprintf("sudo journalctl -u docker -n %d", len)
 }
 
+// ForceSystemd forces the docker daemon to use systemd as cgroup manager
+func (r *Docker) ForceSystemd() error {
+	if !viper.GetBool("force-systemd") {
+		return nil
+	}
+	daemonConfig := `{
+"exec-opts": ["native.cgroupdriver=systemd"],
+"log-driver": "json-file",
+"log-opts": {
+	"max-size": "100m"
+},
+"storage-driver": "overlay2"
+}
+`
+	ma := assets.NewMemoryAsset([]byte(daemonConfig), "/etc/docker", "daemon.json", "0644")
+	return r.Runner.Copy(ma)
+}
+
 // Preload preloads docker with k8s images:
 // 1. Copy over the preloaded tarball into the VM
 // 2. Extract the preloaded tarball to the correct directory