fix(migrate): update lock file path when csp is scaled down (#85)

Signed-off-by: shubham <[email protected]>

docs/migration.md

@@ -125,6 +125,9 @@ I0520 10:01:25.674512       1 pool.go:395] Updating cvr pvc-9cf5a405-12c0-4522-b
 I0520 10:01:25.798889       1 pool.go:80] Successfully migrated spc sparse-claim to cspc
 ```
 
+**<span style="color: red;">Note: In case the job fails for any reason please do not scale up the old CSP deployments. It can lead to data corruption.</span>**
+
+
 ## cStor External Provisioned volumes to cStor CSI volumes
 
 These instructions will guide you through the process of migrating cStor volumes from the old v1apha1 external provisioned spec to v1 CSI spec. 

pkg/migrate/cstor/pool.go

@@ -41,11 +41,6 @@ import (
 )
 
 const (
-	replicaPatch = `{
-	"spec": {
-		"replicas": 0
-	}
-}`
 	cspNameLabel           = "cstorpool.openebs.io/name"
 	cspUIDLabel            = "cstorpool.openebs.io/uid"
 	cspHostnameAnnotation  = "cstorpool.openebs.io/hostname"
@@ -398,7 +393,7 @@ func (c *CSPCMigrator) cspTocspi(cspiObj *cstor.CStorPoolInstance) error {
 	}
 	if cspiObj.Annotations[types.OpenEBSDisableReconcileLabelKey] != "" {
 		klog.Infof("Migrating csp %s to cspi %s", cspObj.Name, cspiObj.Name)
-		err = c.scaleDownDeployment(cspObj, c.OpenebsNamespace)
+		err = c.scaleDownDeployment(cspObj.Name, cspiObj.Name, c.OpenebsNamespace)
 		if err != nil {
 			return err
 		}
@@ -477,24 +472,41 @@ func getCSP(cspLabel string) (*apis.CStorPool, error) {
 
 // The old pool pod should be scaled down before the new cspi pod reconcile is
 // enabled to avoid importing the pool at two places at the same time.
-func (c *CSPCMigrator) scaleDownDeployment(cspObj *apis.CStorPool, openebsNamespace string) error {
-	klog.Infof("Scaling down deployment %s", cspObj.Name)
+func (c *CSPCMigrator) scaleDownDeployment(cspName, cspiName, openebsNamespace string) error {
+	var zero int32 = 0
+	klog.Infof("Scaling down csp deployment %s", cspName)
 	cspDeployList, err := c.KubeClientset.AppsV1().
 		Deployments(openebsNamespace).List(
 		metav1.ListOptions{
-			LabelSelector: "openebs.io/cstor-pool=" + cspObj.Name,
+			LabelSelector: "openebs.io/cstor-pool=" + cspName,
 		})
 	if err != nil {
 		return err
 	}
 	if len(cspDeployList.Items) != 1 {
-		return errors.Errorf("invalid number of csp deployment found for %s: expected 1, got %d", cspObj.Name, len(cspDeployList.Items))
+		return errors.Errorf("invalid number of csp deployment found for %s: expected 1, got %d", cspName, len(cspDeployList.Items))
+	}
+	newCSPDeploy := cspDeployList.Items[0]
+	cspiDeploy, err := c.KubeClientset.AppsV1().
+		Deployments(openebsNamespace).Get(cspiName, metav1.GetOptions{})
+	if err != nil {
+		return errors.Wrapf(err, "failed to get deployment for cspi %s", cspiName)
+	}
+	// While scaling down the csp deployment changing the
+	// volumes as well so that the zrepl.lock file used by
+	// csp and cspi becomes the same to avoid data corruption
+	// due to multiple imports at the same time.
+	newCSPDeploy.Spec.Replicas = &zero
+	newCSPDeploy.Spec.Template.Spec.Volumes = cspiDeploy.Spec.Template.Spec.Volumes
+	patchData, err := GetPatchData(cspDeployList.Items[0], newCSPDeploy)
+	if err != nil {
+		return errors.Wrapf(err, "failed to patch data for csp %s", cspName)
 	}
 	_, err = c.KubeClientset.AppsV1().Deployments(openebsNamespace).
 		Patch(
 			cspDeployList.Items[0].Name,
 			k8stypes.StrategicMergePatchType,
-			[]byte(replicaPatch),
+			patchData,
 		)
 	if err != nil {
 		return err
@@ -503,15 +515,15 @@ func (c *CSPCMigrator) scaleDownDeployment(cspObj *apis.CStorPool, openebsNamesp
 		cspPods, err1 := c.KubeClientset.CoreV1().
 			Pods(openebsNamespace).
 			List(metav1.ListOptions{
-				LabelSelector: "openebs.io/cstor-pool=" + cspObj.Name,
+				LabelSelector: "openebs.io/cstor-pool=" + cspName,
 			})
 		if err1 != nil {
-			klog.Errorf("failed to list pods for csp %s deployment: %s", cspObj.Name, err1.Error())
+			klog.Errorf("failed to list pods for csp %s deployment: %s", cspName, err1.Error())
 		} else {
 			if len(cspPods.Items) == 0 {
 				break
 			}
-			klog.Infof("waiting for csp %s deployment to scale down", cspObj.Name)
+			klog.Infof("waiting for csp %s deployment to scale down", cspName)
 		}
 		time.Sleep(10 * time.Second)
 	}