Add --network-plugin=cni as per afbjorklund's comment

test/integration/start_stop_delete_test.go

@@ -46,6 +46,7 @@ func TestStartStop(t *testing.T) {
 			name:    "crio",
 			runtime: constants.CrioRuntime,
 		},
+		// TODO(tstromberg): Add test for crio w/o cni
 	}
 
 	for _, test := range tests {

test/integration/util/util.go

@@ -184,11 +184,12 @@ func (m *MinikubeRunner) SSH(command string) (string, error) {
 
 func (m *MinikubeRunner) Start() {
 	opts := ""
+	// TODO(tstromberg): Deprecate this in favor of making it possible for tests to define explicit flags.
 	switch r := m.Runtime; r {
 	case constants.ContainerdRuntime:
 		opts = "--container-runtime=containerd --network-plugin=cni --enable-default-cni --docker-opt containerd=/var/run/containerd/containerd.sock"
 	case constants.CrioRuntime:
-		opts = "--container-runtime=crio"
+		opts = "--container-runtime=crio --network-plugin=cni"
 	}
 	m.RunCommand(fmt.Sprintf("start %s %s %s --alsologtostderr --v=5", m.StartArgs, m.Args, opts), true)