overlay node image before bootstrapping if necessary

src/installer/installer.go

@@ -453,6 +453,22 @@ func (i *installer) startBootstrap() error {
 		return err
 	}
 
+	// If we're in a pure RHEL/CentOS environment, we need to overlay the node image
+	// first to have access to e.g. oc, kubelet, cri-o, etc...
+	// https://github.com/openshift/enhancements/pull/1637
+	if !i.ops.FileExists("/usr/bin/oc") {
+		err = i.ops.SystemctlAction("start", "node-image-overlay.service")
+		if err != nil {
+			return err
+		}
+
+		i.waitForNodeImageOverlay(context.Background())
+
+		if !i.ops.FileExists("/usr/bin/oc") {
+			return stderrors.New("/usr/bin/oc still doesn't exist after node image overlay")
+		}
+	}
+
 	servicesToStart := []string{"bootkube.service", "approve-csr.service", "progress.service"}
 	for _, service := range servicesToStart {
 		err = i.ops.SystemctlAction("start", service)
@@ -658,7 +674,7 @@ func (i *installer) waitForBootkube(ctx context.Context) {
 			return
 		case <-time.After(generalWaitInterval):
 			// check if bootkube is done every 5 seconds
-			if _, err := i.ops.ExecPrivilegeCommand(nil, "stat", "/opt/openshift/.bootkube.done"); err == nil {
+			if i.ops.FileExists("/opt/openshift/.bootkube.done") {
 				// in case bootkube is done log the status and return
 				i.log.Info("bootkube service completed")
 				out, _ := i.ops.ExecPrivilegeCommand(nil, "systemctl", "status", "bootkube.service")
@@ -669,6 +685,25 @@ func (i *installer) waitForBootkube(ctx context.Context) {
 	}
 }
 
+func (i *installer) waitForNodeImageOverlay(ctx context.Context) {
+	i.log.Infof("Waiting for node image overlay to complete")
+
+	for {
+		select {
+		case <-ctx.Done():
+			i.log.Info("Context cancelled, terminating wait for node image overlay\n")
+			return
+		case <-time.After(generalWaitInterval):
+			out, err := i.ops.ExecPrivilegeCommand(nil, "systemctl", "is-active", "node-image-overlay.service")
+			if err == nil {
+				i.log.Info("node image overlay service completed")
+				return
+			}
+			i.log.Debugf("node image overlay service not yet active: %s", out)
+		}
+	}
+}
+
 func (i *installer) waitForController(kc k8s_client.K8SClient) error {
 	i.log.Infof("Waiting for controller to be ready")
 	i.UpdateHostInstallProgress(models.HostStageWaitingForController, "waiting for controller pod ready event")

src/main/drymock/dry_mode_k8s_mock.go

@@ -22,7 +22,7 @@ import (
 func mockNodeList(mockk8sclient *k8s_client.MockK8SClient, clusterHosts config.DryClusterHosts, o ops.Ops) v1.NodeList {
 	nodeListPopulated := v1.NodeList{}
 	for _, clusterHost := range clusterHosts {
-		if !o.DryRebootHappened(clusterHost.RebootMarkerPath) {
+		if !o.FileExists(clusterHost.RebootMarkerPath) {
 			// Host didn't even reboot yet, don't pretend it's a node
 			continue
 		}
@@ -103,7 +103,7 @@ func PrepareControllerDryMock(mockk8sclient *k8s_client.MockK8SClient, logger *l
 		mcsLogs := ""
 		for _, clusterHost := range clusterHosts {
 			// Add IP access log for each IP, this is how the controller determines which node has downloaded the ignition
-			if !o.DryRebootHappened(clusterHost.RebootMarkerPath) {
+			if !o.FileExists(clusterHost.RebootMarkerPath) {
 				// Host didn't even reboot yet, don't pretend it fetched the ignition
 				continue
 			}

src/ops/ops.go

@@ -65,7 +65,7 @@ type Ops interface {
 	EvaluateDiskSymlink(string) string
 	FormatDisk(string) error
 	CreateManifests(string, []byte) error
-	DryRebootHappened(markerPath string) bool
+	FileExists(markerPath string) bool
 	ExecPrivilegeCommand(liveLogger io.Writer, command string, args ...string) (string, error)
 	ReadFile(filePath string) ([]byte, error)
 	GetEncapsulatedMC(ignitionPath string) (*mcfgv1.MachineConfig, error)
@@ -434,7 +434,7 @@ func (o *ops) GetMCSLogs() (string, error) {
 		mcsLogs := ""
 		for _, clusterHost := range o.installerConfig.ParsedClusterHosts {
 			// Add IP access log for each IP, this is how the installer determines which node has downloaded the ignition
-			if !o.DryRebootHappened(clusterHost.RebootMarkerPath) {
+			if !o.FileExists(clusterHost.RebootMarkerPath) {
 				// Host didn't even reboot yet, don't pretend it fetched the ignition
 				continue
 			}
@@ -648,11 +648,12 @@ func (o *ops) CreateManifests(kubeconfig string, content []byte) error {
 	return nil
 }
 
-// DryRebootHappened checks if a reboot happened according to a particular reboot marker path
-// The dry run installer creates this file on "Reboot" (instead of actually rebooting)
-// We use this function to check whether the given node in the cluster have already rebooted
-func (o *ops) DryRebootHappened(markerPath string) bool {
-	_, err := o.ExecPrivilegeCommand(nil, "stat", markerPath)
+// FileExists checks if a file exists. It's notably used to check if a
+// dry reboot happened. The dry run installer creates the marker file on
+// "Reboot" (instead of actually rebooting) We use this function to check
+// whether the given node in the cluster have already rebooted
+func (o *ops) FileExists(path string) bool {
+	_, err := o.ExecPrivilegeCommand(nil, "stat", path)
 
 	return err == nil
 }