Update documentation, comments

docs/SplunkOperatorUpgrade.md

@@ -142,18 +142,18 @@ kubectl get pods splunk-<crname>-monitoring-console-0 -o yaml | grep -i image
 image: splunk/splunk:9.1.3
 imagePullPolicy: IfNotPresent
 ```
-## Splunk Enterprise Cluster upgrade example
+## Splunk Enterprise Cluster upgrade
 
-This is an example of the process followed by the Splunk Operator if the operator version is upgraded and a later Splunk Enterprise Docker image is available:
-​
+The Splunk Operator mostly adheres to the upgrade path steps delineated in the Splunk documentation.  All pods of the custom resources are deleted and redeployed sequentially. In cases where multi-zone Indexer clusters are utilized, they undergo redeployment zone by zone. Each pod upgrade is meticulously verified to ensure a successful process, with thorough checks conducted to confirm that everything is functioning as expected. If there are multiple pods per Custom Resource, the pods are terminated and re-deployed in a descending order with the highest numbered pod going first.
+
+This is an example of the process followed by the Splunk Operator if the operator version is upgraded and a later Splunk Enterprise Docker image is available. Pod termination and redeployment occur in the below mentioned order based on the recommended upgrade path:
 
-1. Initiation of a new Splunk Operator pod will lead to the termination of the existing operator pod.
-2. All existing License Manager, Standalone, Monitoring Console, Cluster Manager, Search Head, ClusterManager, and Indexer pods will undergo termination for subsequent redeployment with upgraded specifications.
-3. The Splunk Operator adheres to the upgrade path steps delineated in the Splunk documentation. Pod termination and redeployment occur in a specific order based on the recommended upgrade path.
-4. Standalone or License manager will be the first to be redeployed
-5. Next ClusterManager pod will be redeployed, next the Monitoring Console pod undergoes termination and redeployment.
-6. Subsequently, the Search Head cluster pods connected to it are terminated and redeployed.
-7. Afterwards, all pods in the Indexer cluster are redeployed sequentially. In cases where multi-zone Indexer clusters are utilized, they undergo redeployment zone by zone.
-8. Each pod upgrade is meticulously verified to ensure a successful process, with thorough checks conducted to confirm that everything is functioning as expected.
+1. Splunk Operator deployment pod
+2. Standalone
+3. License manager
+4. ClusterManager
+5. Search Head cluster
+6. Indexer Cluster
+7. Monitoring Console
 
-* Note: If there are multiple pods per Custom Resource, the pods are terminated and re-deployed in a descending order with the highest numbered pod going first
+Note: The order above assumes that the custom resources are linked via references. If there are Custom resources without references they will be deleted/redeployed indepedentlty of the order.

pkg/splunk/enterprise/upgrade.go

@@ -3,6 +3,7 @@ package enterprise
 import (
 	"context"
 	"fmt"
+
 	enterpriseApi "github.com/splunk/splunk-operator/api/v4"
 	splclient "github.com/splunk/splunk-operator/pkg/splunk/client"
 	splcommon "github.com/splunk/splunk-operator/pkg/splunk/common"
@@ -259,14 +260,16 @@ MonitoringConsole:
 			runtime.InNamespace(cr.GetNamespace()),
 		}
 
+		// get the list of cluster managers
 		clusterManagerList := &enterpriseApi.ClusterManagerList{}
-		// get the list cluster manager which have mc reference
 		err := c.List(ctx, clusterManagerList, listOpts...)
 		if err != nil && err.Error() != "NotFound" {
 			eventPublisher.Warning(ctx, "UpgradePathValidation", fmt.Sprintf("Could not find the Cluster Manager list. Reason %v", err))
 			scopedLog.Error(err, "Unable to get clusterManager list")
 			return false, err
 		}
+
+		// Run through list, if it has the MC reference, bail out if it is NOT ready
 		for _, cm := range clusterManagerList.Items {
 			if cm.Spec.MonitoringConsoleRef.Name == cr.GetName() {
 				if cm.Status.Phase != enterpriseApi.PhaseReady {
@@ -276,15 +279,16 @@ MonitoringConsole:
 			}
 		}
 
+		// get the list of search head clusters
 		searchHeadClusterList := &enterpriseApi.SearchHeadClusterList{}
-		// get the list search head which have mc reference
 		err = c.List(ctx, searchHeadClusterList, listOpts...)
 		if err != nil && err.Error() != "NotFound" {
 			eventPublisher.Warning(ctx, "UpgradePathValidation", fmt.Sprintf("Could not find the Search Head Cluster list. Reason %v", err))
 			scopedLog.Error(err, "Unable to get Search Head Cluster list")
 			return false, err
 		}
 
+		// Run through list, if it has the MC reference, bail out if it is NOT ready
 		for _, shc := range searchHeadClusterList.Items {
 			if shc.Spec.MonitoringConsoleRef.Name == cr.GetName() {
 				if shc.Status.Phase != enterpriseApi.PhaseReady {
@@ -293,15 +297,17 @@ MonitoringConsole:
 				}
 			}
 		}
+
+		// get the list of indexer clusters
 		indexerClusterList := &enterpriseApi.IndexerClusterList{}
-		// get the list indexer which have mc reference
 		err = c.List(ctx, indexerClusterList, listOpts...)
 		if err != nil && err.Error() != "NotFound" {
 			eventPublisher.Warning(ctx, "UpgradePathValidation", fmt.Sprintf("Could not find the Indexer list. Reason %v", err))
 			scopedLog.Error(err, "Unable to get indexer list")
 			return false, err
 		}
 
+		// Run through list, if it has the MC reference, bail out if it is NOT ready
 		for _, idx := range indexerClusterList.Items {
 			if idx.Name == cr.GetName() {
 				if idx.Status.Phase != enterpriseApi.PhaseReady {
@@ -310,14 +316,17 @@ MonitoringConsole:
 				}
 			}
 		}
+
+		// get the list of standalones
 		standaloneList := &enterpriseApi.IndexerClusterList{}
-		// get the list standalone which have mc reference
 		err = c.List(ctx, standaloneList, listOpts...)
 		if err != nil && err.Error() != "NotFound" {
 			eventPublisher.Warning(ctx, "UpgradePathValidation", fmt.Sprintf("Could not find the Standalone list. Reason %v", err))
 			scopedLog.Error(err, "Unable to get standalone list")
 			return false, err
 		}
+
+		// Run through list, if it has the MC reference, bail out if it is NOT ready
 		for _, stdln := range standaloneList.Items {
 			if stdln.Name == cr.GetName() {
 				if stdln.Status.Phase != enterpriseApi.PhaseReady {