Do not set ongoing-upgrade in IC configmap

Single-zone mode is only needed during a 4.13->4.14 upgrade. Switching back to it is not supported. As a consequence, we can further simplify the upgrade logic and remove the "ongoing-upgrade" flag: only CNO pushes the IC configmap to track the upgrade progress, so an upgrade to IC is ongoing if the configmap exists.

Signed-off-by: Riccardo Ravaioli <rravaiol@redhat.com>

pkg/controller/statusmanager/pod_status.go

@@ -256,15 +256,14 @@ func (status *StatusManager) SetFromPods() {
 	if status.isOVNKubernetes != nil && *status.isOVNKubernetes {
 		// hack for 2-phase upgrade from non-IC to IC ovnk:
 		// don't update the version field until phase 2 is over
-		if icConfigMap, err := util.GetInterConnectConfigMap(status.client.ClientFor("").Kubernetes()); err == nil {
-			// When an upgrade from <= 4.13 is ongoing, the IC configmap exists and exhibits ongoing-upgrade=''.
-			// When multizone control-plane and node have been rolled out (end of phase 2), the configmap is deleted.
-			if _, ok := icConfigMap.Data["ongoing-upgrade"]; ok {
-				reachedAvailableLevel = false
-			}
+		if _, err := util.GetInterConnectConfigMap(status.client.ClientFor("").Kubernetes()); err == nil {
+			// When an upgrade from <= 4.13 is ongoing, CNO has pushed an IC configmap to track it.
+			// The configmap is deleted when multizone control-plane and node have been rolled out (end of phase 2).
+			reachedAvailableLevel = false
+
 		} else if !apierrors.IsNotFound(err) {
 			log.Printf("Failed to retrieve interconnect configmap: %v", err)
-			// don't risk reporting new version during zone mode migration until configmap retrieval is successful
+			// don't risk reporting the new version during the upgrade to IC until the configmap retrieval is successful
 			reachedAvailableLevel = false
 		}
 	}

pkg/network/ovn_kubernetes.go

@@ -1256,20 +1256,18 @@ const (
 )
 
 type targetZoneModeType struct {
-	// zoneMode indicates the target zone mode that CNO is supposed to converge to.
+	// zoneMode indicates the target zone mode that CNO is supposed to converge to. It defaults
+	// multizone.
 	zoneMode InterConnectZoneMode
-	// "configMapFound" indicates whether the interconnect configmap was found; when not found,
-	// the zone mode defaults to multizone.
+	// "configMapFound" indicates whether the interconnect configmap was found. The configmap
+	// is created by CNO itself during a 4.13->4.14 upgrade and deleted once the upgrade is over.
 	configMapFound bool
-	// ongoingUpgrade is true when the configmap was pushed by CNO itself; it is used by status manager
-	// to know it has to keep reporting the old version when this parameter is set.
-	ongoingUpgrade bool
 	// fastForwardToMultiZone can be manually set by the cluster admin through the interconnect configmap
 	// in order to force CNO to deploy multizone OVNK regardless of the current status of OVNK components
-	// throughout an upgrade to interconnect. This would effectively get the cluster out of phase 1 and phase 2
+	// during an upgrade to interconnect. This would effectively get the cluster out of phase 1 and phase 2
 	// and make OVNK jump to the YAMLs in the multi-zone-interconnect folder.
 	// This can be useful in case of problems during  upgrades, if ever the logic in prepareUpgradeToInterconnect
-	// is not moving forward (e.g. one or more nodes are down and ovnk node is considered as "progressing")
+	// is not moving forward (e.g. one or more nodes are down and ovnkube-node is considered as "progressing")
 	fastForwardToMultiZone bool
 }
 
@@ -1305,10 +1303,6 @@ func getTargetInterConnectZoneMode(kubeClient cnoclient.Client) (targetZoneModeT
 		targetZoneMode.zoneMode = zoneModeMultiZone
 	}
 
-	if _, ok := interConnectConfigMap.Data["ongoing-upgrade"]; ok {
-		targetZoneMode.ongoingUpgrade = true
-	}
-
 	if _, ok := interConnectConfigMap.Data["fast-forward-to-multizone"]; ok {
 		targetZoneMode.fastForwardToMultiZone = true
 		if targetZoneMode.zoneMode != zoneModeMultiZone {
@@ -2396,7 +2390,7 @@ func doesVersionEnableInterConnect(string) bool {
 // If we're upgrading from a 4.13 cluster, which has no OVN InterConnect support, three phases are necessary.
 // Phase 1:
 //
-//	a) prepareUpgradeToInterConnect pushes a configMap with zone-mode=singlezone, ongoing-upgrade='';
+//	a) prepareUpgradeToInterConnect pushes a configMap with zone-mode=singlezone;
 //	b) renderOVNKubernetes selects the YAMLs from the single-zone folder
 //	   (node DaemonSet, master DaemonSet [StatefulSet for hypershift], ovnkube-sbdb route [hypershift]);
 //	c) shouldUpdateOVNKonUpgrade rolls out first node DaemonSet then master DaemonSet/StatefulSet in single-zone mode
@@ -2426,8 +2420,8 @@ func prepareUpgradeToInterConnect(ovn bootstrap.OVNBootstrapResult, client cnocl
 
 	// [start of phase 1]
 	// if node and master DaemonSets are <= 4.13 (no IC support) and we're upgrading to >= 4.14 (IC),
-	// go through an intermediate step with IC single-zone DaemonSets. Track this temporary state
-	// by pushing a configmap.
+	// go through an intermediate step with IC single-zone DaemonSets. Track that the upgrade is ongoing
+	// by pushing a configmap with the zone mode that CNO is converging to.
 	if ovn.NodeUpdateStatus != nil && ovn.MasterUpdateStatus != nil && ovn.ControlPlaneUpdateStatus == nil &&
 		!ovn.NodeUpdateStatus.InterConnectEnabled &&
 		!ovn.MasterUpdateStatus.InterConnectEnabled &&
@@ -2443,10 +2437,6 @@ func prepareUpgradeToInterConnect(ovn bootstrap.OVNBootstrapResult, client cnocl
 			},
 			Data: map[string]string{
 				"zone-mode": fmt.Sprint(zoneModeSingleZone),
-				// we lookup ongoing-upgrade in SetFromPods (pod_status.go) to distinguish a
-				// configmap pushed during a non-IC-> IC upgrade from one that is added
-				// outside of an upgrade by a cluster admin to change the zone mode.
-				"ongoing-upgrade": "",
 			},
 		}
 		if err := client.ClientFor("").CRClient().Create(context.TODO(), configMap); err != nil {
@@ -2455,7 +2445,7 @@ func prepareUpgradeToInterConnect(ovn bootstrap.OVNBootstrapResult, client cnocl
 		targetZoneMode.configMapFound = true
 		targetZoneMode.zoneMode = zoneModeSingleZone
 
-	} else if isMigrationToMultiZoneAboutToStart(ovn, targetZoneMode, true) && targetZoneMode.ongoingUpgrade && !targetZoneMode.fastForwardToMultiZone {
+	} else if isMigrationToMultiZoneAboutToStart(ovn, targetZoneMode, true) && targetZoneMode.configMapFound && !targetZoneMode.fastForwardToMultiZone {
 		// [start of phase 2]
 		// if node and master DaemonSets have already upgraded to >= 4.14 single zone and
 		// we previously pushed a configmap for single zone,
@@ -2482,7 +2472,7 @@ func prepareUpgradeToInterConnect(ovn bootstrap.OVNBootstrapResult, client cnocl
 
 		targetZoneMode.zoneMode = zoneModeMultiZone
 
-	} else if isMigrationToMultiZoneComplete(ovn, targetZoneMode) && targetZoneMode.ongoingUpgrade {
+	} else if isMigrationToMultiZoneComplete(ovn, targetZoneMode) && targetZoneMode.configMapFound {
 		// [after completion of phase 2]
 		// daemonsets have rolled out in multizone mode
 		// Remove the configmap: this won't trigger any further roll out, but along with the annotation
@@ -2496,7 +2486,6 @@ func prepareUpgradeToInterConnect(ovn bootstrap.OVNBootstrapResult, client cnocl
 				return fmt.Errorf("upgrade to interconnect, end of phase2: could not delete interconnect configmap: %w", err)
 			}
 		}
-		targetZoneMode.ongoingUpgrade = false
 		targetZoneMode.configMapFound = false
 
 		// HACK Once we're here, there are no more updates to the DaemonSets and CNO won't update
@@ -2505,7 +2494,7 @@ func prepareUpgradeToInterConnect(ovn bootstrap.OVNBootstrapResult, client cnocl
 	}
 
 	// Print IC upgrade status when phase 1 or phase 2 are ongoing
-	if targetZoneMode.ongoingUpgrade {
+	if targetZoneMode.configMapFound {
 		if targetZoneMode.zoneMode == zoneModeSingleZone &&
 			ovn.NodeUpdateStatus != nil && ovn.MasterUpdateStatus != nil && ovn.ControlPlaneUpdateStatus == nil &&
 			(ovn.NodeUpdateStatus.Progressing || ovn.MasterUpdateStatus.Progressing) {