Remove Elasticsearch 6.x support

NOTICE.txt

@@ -1,4 +1,4 @@
-Copyright 2018-2025 Elasticsearch BV
+Copyright 2018-2026 Elasticsearch BV
 
 This product includes software developed by The Apache Software
 Foundation (http://www.apache.org/).

docs/reference/api-reference/main.md

@@ -1649,8 +1649,6 @@ UpdateStrategy specifies how updates to the cluster should be performed.
 
 
 
-
-
 % TODO add function to crd-ref-docs return anchor used in links docs-v3 does not seem to produce valid markdown anchors
 ## enterprisesearch.k8s.elastic.co/v1 [#enterprisesearchk8selasticcov1]
 

pkg/apis/elasticsearch/v1/fields.go

@@ -13,12 +13,10 @@ var MinReadinessPortVersion = version.MinFor(8, 2, 0)
 const (
 	ClusterName = "cluster.name"
 
-	DiscoveryZenMinimumMasterNodes = "discovery.zen.minimum_master_nodes"
-	ClusterInitialMasterNodes      = "cluster.initial_master_nodes"
+	ClusterInitialMasterNodes = "cluster.initial_master_nodes"
 
-	DiscoveryZenHostsProvider = "discovery.zen.hosts_provider" // ES < 7.X
-	DiscoverySeedProviders    = "discovery.seed_providers"     // ES >= 7.X
-	DiscoverySeedHosts        = "discovery.seed_hosts"         // ES >= 7.X
+	DiscoverySeedProviders = "discovery.seed_providers"
+	DiscoverySeedHosts     = "discovery.seed_hosts"
 
 	ReadinessPort = "readiness.port" // ES >= 8.2.0
 
@@ -38,12 +36,8 @@ const (
 	ShardAwarenessAttributes = "cluster.routing.allocation.awareness.attributes"
 	NodeAttr                 = "node.attr"
 
-	XPackSecurityAuthcRealmsFileFile1Order     = "xpack.security.authc.realms.file.file1.order"     // 7.x realm syntax
-	XPackSecurityAuthcRealmsFile1Order         = "xpack.security.authc.realms.file1.order"          // 6.x realm syntax
-	XPackSecurityAuthcRealmsFile1Type          = "xpack.security.authc.realms.file1.type"           // 6.x realm syntax
-	XPackSecurityAuthcRealmsNativeNative1Order = "xpack.security.authc.realms.native.native1.order" // 7.x realm syntax
-	XPackSecurityAuthcRealmsNative1Order       = "xpack.security.authc.realms.native1.order"        // 6.x realm syntax
-	XPackSecurityAuthcRealmsNative1Type        = "xpack.security.authc.realms.native1.type"         // 6.x realm syntax
+	XPackSecurityAuthcRealmsFileFile1Order     = "xpack.security.authc.realms.file.file1.order"
+	XPackSecurityAuthcRealmsNativeNative1Order = "xpack.security.authc.realms.native.native1.order"
 
 	XPackSecurityAuthcReservedRealmEnabled          = "xpack.security.authc.reserved_realm.enabled"
 	XPackSecurityEnabled                            = "xpack.security.enabled"
@@ -72,7 +66,6 @@ var UnsupportedSettings = []string{
 	ClusterName,
 	DiscoverySeedHosts,
 	DiscoverySeedProviders,
-	DiscoveryZenMinimumMasterNodes,
 	ClusterInitialMasterNodes,
 	NetworkHost,
 	NetworkPublishHost,

pkg/apis/elasticsearch/v1beta1/elasticsearch_types.go

@@ -193,10 +193,6 @@ type ElasticsearchStatus struct {
 	Phase                          ElasticsearchOrchestrationPhase `json:"phase,omitempty"`
 }
 
-type ZenDiscoveryStatus struct {
-	MinimumMasterNodes int `json:"minimumMasterNodes,omitempty"`
-}
-
 // IsDegraded returns true if the current status is worse than the previous.
 func (es ElasticsearchStatus) IsDegraded(prev ElasticsearchStatus) bool {
 	return es.Health.Less(prev.Health)

pkg/apis/elasticsearch/v1beta1/fields.go

@@ -7,11 +7,9 @@ package v1beta1
 const (
 	ClusterName = "cluster.name"
 
-	DiscoveryZenMinimumMasterNodes = "discovery.zen.minimum_master_nodes"
-	ClusterInitialMasterNodes      = "cluster.initial_master_nodes"
+	ClusterInitialMasterNodes = "cluster.initial_master_nodes"
 
-	DiscoveryZenHostsProvider = "discovery.zen.hosts_provider" // ES < 7.X
-	DiscoverySeedProviders    = "discovery.seed_providers"     // ES >= 7.X
+	DiscoverySeedProviders = "discovery.seed_providers"
 
 	NetworkHost        = "network.host"
 	NetworkPublishHost = "network.publish_host"
@@ -21,12 +19,8 @@ const (
 	PathData = "path.data"
 	PathLogs = "path.logs"
 
-	XPackSecurityAuthcRealmsFileFile1Order     = "xpack.security.authc.realms.file.file1.order"     // 7.x realm syntax
-	XPackSecurityAuthcRealmsFile1Order         = "xpack.security.authc.realms.file1.order"          // 6.x realm syntax
-	XPackSecurityAuthcRealmsFile1Type          = "xpack.security.authc.realms.file1.type"           // 6.x realm syntax
-	XPackSecurityAuthcRealmsNativeNative1Order = "xpack.security.authc.realms.native.native1.order" // 7.x realm syntax
-	XPackSecurityAuthcRealmsNative1Order       = "xpack.security.authc.realms.native1.order"        // 6.x realm syntax
-	XPackSecurityAuthcRealmsNative1Type        = "xpack.security.authc.realms.native1.type"         // 6.x realm syntax
+	XPackSecurityAuthcRealmsFileFile1Order     = "xpack.security.authc.realms.file.file1.order"
+	XPackSecurityAuthcRealmsNativeNative1Order = "xpack.security.authc.realms.native.native1.order"
 
 	XPackSecurityAuthcReservedRealmEnabled          = "xpack.security.authc.reserved_realm.enabled"
 	XPackSecurityEnabled                            = "xpack.security.enabled"
@@ -43,7 +37,6 @@ const (
 
 var UnsupportedSettings = []string{
 	ClusterName,
-	DiscoveryZenMinimumMasterNodes,
 	ClusterInitialMasterNodes,
 	NetworkHost,
 	NetworkPublishHost,

pkg/apis/elasticsearch/v1beta1/validations_test.go

@@ -88,7 +88,7 @@ func Test_hasMaster(t *testing.T) {
 	}{
 		{
 			name:         "no topology",
-			es:           es("6.8.0"),
+			es:           es("7.17.0"),
 			expectErrors: true,
 		},
 		{
@@ -543,7 +543,7 @@ func TestValidation_noDowngrades(t *testing.T) {
 		{
 			name:         "no validation on create",
 			current:      nil,
-			proposed:     es("6.8.0"),
+			proposed:     es("7.17.0"),
 			expectErrors: false,
 		},
 		{
@@ -604,7 +604,7 @@ func Test_validUpgradePath(t *testing.T) {
 		},
 		{
 			name:         "in range accepted",
-			current:      es("6.8.0"),
+			current:      es("7.0.0"),
 			proposed:     es("7.17.0"),
 			expectErrors: false,
 		},

pkg/controller/association/controller/apm_es.go

@@ -125,18 +125,10 @@ func getAPMElasticsearchRoles(associated commonv1.Associated) (string, error) {
 		}, ","), nil
 	}
 
-	// 7.1.x to 7.4.x
-	if v.GTE(version.From(7, 1, 0)) {
-		return strings.Join([]string{
-			user.ApmUserRoleV7, // Retrieve cluster details (e.g. version) and manage apm-* indices
-			"ingest_admin",     // Set up index templates
-			"apm_system",       // To collect metrics about APM Server
-		}, ","), nil
-	}
-
-	// 6.8
+	// 7.1.x to 7.4.x (and fallback for any older 7.x versions)
 	return strings.Join([]string{
-		user.ApmUserRoleV6, // Retrieve cluster details (e.g. version) and manage apm-* indices
+		user.ApmUserRoleV7, // Retrieve cluster details (e.g. version) and manage apm-* indices
+		"ingest_admin",     // Set up index templates
 		"apm_system",       // To collect metrics about APM Server
 	}, ","), nil
 }

pkg/controller/association/controller/apm_es_test.go

@@ -22,22 +22,13 @@ func Test_getAPMElasticsearchRoles(t *testing.T) {
 		wantErr bool
 	}{
 		{
-			name: "Test roles for APM Server v6.8.0",
+			name: "Test roles for APM Server v7.0.0",
 			args: args{
 				associated: &apmv1.ApmServer{
-					Spec: apmv1.ApmServerSpec{Version: "6.8.0"},
+					Spec: apmv1.ApmServerSpec{Version: "7.0.0"},
 				},
 			},
-			want: "eck_apm_user_role_v6,apm_system",
-		},
-		{
-			name: "Test roles for APM Server v6.8.99",
-			args: args{
-				associated: &apmv1.ApmServer{
-					Spec: apmv1.ApmServerSpec{Version: "6.8.99"},
-				},
-			},
-			want: "eck_apm_user_role_v6,apm_system",
+			want: "eck_apm_user_role_v7,ingest_admin,apm_system",
 		},
 		{
 			name: "Test roles for APM Server v7.1.0",

pkg/controller/common/expectations/expectations.go

@@ -46,8 +46,8 @@ Things that could happen without this mechanism in place:
 - delete more than one master node at a time
 - outgrow the changeBudget during upscale and downscales
 - clear shards allocation excludes for a node that is not removed yet
-- update zen1/zen2 minimum_master_nodes/initial_master_nodes based on the wrong number of nodes
-- update zen1/zen2 minimum_master_nodes/initial_master_nodes based on the wrong nodes specification (ignoring master->data upgrades)
+- update zen2 initial_master_nodes based on the wrong number of nodes
+- update zen2 initial_master_nodes based on the wrong nodes specification (ignoring master->data upgrades)
 - clear voting_config_exclusions while a Pod has not finished its restart yet (or maybe just started)
 
 ## What if the operator restarts?
@@ -64,7 +64,7 @@ No. In most situations, it's totally fine to rely on Kubernetes optimistic locki
 * if we delete a resource that does not exist, the operation fails
 
 The only cases where we need it are (so far):
-- when interacting with external systems own orchestration mechanism (Elasticsearch zen1/zen2)
+- when interacting with external systems own orchestration mechanism (Elasticsearch zen2)
 - when trying to control how many creations/deletions/upgrades happen in parallel
 
 ## Where does it come from?

pkg/controller/elasticsearch/bootstrap/bootstrap.go

@@ -45,8 +45,7 @@ func ReconcileClusterUUID(ctx context.Context, k8sClient k8s.Client, cluster *es
 	clusterUUID, err := getClusterUUID(ctx, esClient)
 	if err != nil {
 		// There was an error while retrieving the UUID of the Elasticsearch cluster.
-		// For example, it could be the case with ES 6.x if the cluster does not have a master yet, in this case an
-		// API call to get the cluster UUID returns a 503 error.
+		// For example, if the cluster does not have a master yet, an API call to get the cluster UUID returns a 503 error.
 		// However we don't want to stop the reconciliation loop here because it could prevent the user to apply
 		// an update to the cluster spec to fix a problem.
 		// Therefore we just log the error and notify the driver that the reconciliation should be eventually re-queued.

pkg/controller/elasticsearch/client/base.go

@@ -179,20 +179,17 @@ func (c *baseClient) request(
 
 func versioned(b *baseClient, v version.Version) Client {
 	b.version = v
-	v6 := clientV6{
+	v7 := clientV7{
 		baseClient: *b,
 	}
 	switch v.Major {
-	case 7:
-		return &clientV7{
-			clientV6: v6,
-		}
 	case 8, 9:
 		return &clientV8{
-			clientV7: clientV7{clientV6: v6},
+			clientV7: v7,
 		}
 	default:
-		return &v6
+		// Default to v7 client for version 7.x and any future versions
+		return &v7
 	}
 }
 

pkg/controller/elasticsearch/client/client.go

@@ -91,8 +91,6 @@ type Client interface {
 	GetClusterHealthWaitForAllEvents(ctx context.Context) (Health, error)
 	// GetClusterState calls the _cluster/state api.
 	GetClusterState(ctx context.Context) (ClusterState, error)
-	// SetMinimumMasterNodes sets the transient and persistent setting of the same name in cluster settings.
-	SetMinimumMasterNodes(ctx context.Context, n int) error
 	// ReloadSecureSettings will decrypt and re-read the entire keystore, on every cluster node,
 	// but only the reloadable secure settings will be applied
 	ReloadSecureSettings(ctx context.Context) error