From e24fd060220eb9467f0bec6f8e73fea8fb0f74f0 Mon Sep 17 00:00:00 2001
From: George Kechagias <geo.kechagias@gmail.com>
Date: Fri, 28 Nov 2025 18:13:27 +0200
Subject: [PATCH 01/12] K8SPXC-1688 support adding existing pvcs to pxc
 instances

---
 ...pxc.percona.com_perconaxtradbclusters.yaml |  57 ++++++++
 deploy/bundle.yaml                            |  57 ++++++++
 deploy/cr.yaml                                |   5 +
 deploy/crd.yaml                               |  57 ++++++++
 deploy/cw-bundle.yaml                         |  57 ++++++++
 pkg/apis/pxc/v1/pxc_types.go                  | 131 ++++++++++++++++++
 pkg/apis/pxc/v1/zz_generated.deepcopy.go      |  20 +++
 pkg/pxc/app/statefulset/node.go               |   5 +-
 pkg/pxc/statefulset.go                        |   5 +
 9 files changed, 393 insertions(+), 1 deletion(-)

diff --git a/config/crd/bases/pxc.percona.com_perconaxtradbclusters.yaml b/config/crd/bases/pxc.percona.com_perconaxtradbclusters.yaml
index c8bf4ccee9..a014a672e0 100644
--- a/config/crd/bases/pxc.percona.com_perconaxtradbclusters.yaml
+++ b/config/crd/bases/pxc.percona.com_perconaxtradbclusters.yaml
@@ -1746,6 +1746,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
@@ -5311,6 +5330,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
@@ -8332,6 +8370,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
diff --git a/deploy/bundle.yaml b/deploy/bundle.yaml
index 6d0e6ee75d..9fd3435406 100644
--- a/deploy/bundle.yaml
+++ b/deploy/bundle.yaml
@@ -3053,6 +3053,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
@@ -6618,6 +6637,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
@@ -9639,6 +9677,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
diff --git a/deploy/cr.yaml b/deploy/cr.yaml
index 42c7fd226e..4bd1f4d257 100644
--- a/deploy/cr.yaml
+++ b/deploy/cr.yaml
@@ -63,6 +63,11 @@ spec:
     size: 3
     image: perconalab/percona-xtradb-cluster-operator:main-pxc8.0
     autoRecovery: true
+#    extraPVCs:
+#      - name: extra-data-volume
+#        claimName: kech-extra-storage
+#        mountPath: /var/lib/mysql-extra
+#        readOnly: false
 #    mysqlAllocator: jemalloc
 #    expose:
 #      enabled: true
diff --git a/deploy/crd.yaml b/deploy/crd.yaml
index bece937fe6..162400cf45 100644
--- a/deploy/crd.yaml
+++ b/deploy/crd.yaml
@@ -3053,6 +3053,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
@@ -6618,6 +6637,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
@@ -9639,6 +9677,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
diff --git a/deploy/cw-bundle.yaml b/deploy/cw-bundle.yaml
index 7246088a7b..21d1de360b 100644
--- a/deploy/cw-bundle.yaml
+++ b/deploy/cw-bundle.yaml
@@ -3053,6 +3053,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
@@ -6618,6 +6637,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
@@ -9639,6 +9677,25 @@ spec:
                       rule: '!(has(self.loadBalancerClass)) || self.type == ''LoadBalancer'''
                   externalTrafficPolicy:
                     type: string
+                  extraPVCs:
+                    items:
+                      properties:
+                        claimName:
+                          type: string
+                        mountPath:
+                          type: string
+                        name:
+                          type: string
+                        readOnly:
+                          type: boolean
+                        subPath:
+                          type: string
+                      required:
+                      - claimName
+                      - mountPath
+                      - name
+                      type: object
+                    type: array
                   gracePeriod:
                     format: int64
                     type: integer
diff --git a/pkg/apis/pxc/v1/pxc_types.go b/pkg/apis/pxc/v1/pxc_types.go
index 75c3c1c8bd..2ac147a82f 100644
--- a/pkg/apis/pxc/v1/pxc_types.go
+++ b/pkg/apis/pxc/v1/pxc_types.go
@@ -22,6 +22,7 @@ import (
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/util/intstr"
 	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/log"
 
 	"github.com/percona/percona-xtradb-cluster-operator/pkg/pxc/users"
 	"github.com/percona/percona-xtradb-cluster-operator/pkg/pxctls"
@@ -530,6 +531,12 @@ func (cr *PerconaXtraDBCluster) Validate() error {
 		}
 	}
 
+	if c.PXC != nil && len(c.PXC.ExtraPVCs) > 0 {
+		if err := ValidateExtraPVCs(c.PXC.ExtraPVCs); err != nil {
+			return errors.Wrap(err, "PXC: validate extraPVCs")
+		}
+	}
+
 	return nil
 }
 
@@ -607,6 +614,7 @@ type PodSpec struct {
 	Sidecars                    []corev1.Container                `json:"sidecars,omitempty"`
 	SidecarVolumes              []corev1.Volume                   `json:"sidecarVolumes,omitempty"`
 	SidecarPVCs                 []corev1.PersistentVolumeClaim    `json:"sidecarPVCs,omitempty"`
+	ExtraPVCs                   []ExtraPVC                        `json:"extraPVCs,omitempty"`
 	RuntimeClassName            *string                           `json:"runtimeClassName,omitempty"`
 	HookScript                  string                            `json:"hookScript,omitempty"`
 	Lifecycle                   corev1.Lifecycle                  `json:"lifecycle,omitempty"`
@@ -928,6 +936,29 @@ type VolumeSpec struct {
 	PersistentVolumeClaim *corev1.PersistentVolumeClaimSpec `json:"persistentVolumeClaim,omitempty"`
 }
 
+// ExtraPVC allows mounting an existing PersistentVolumeClaim to the PXC container.
+type ExtraPVC struct {
+	// Name of the volume as it will be referenced in the pod
+	// +kubebuilder:validation:Required
+	Name string `json:"name"`
+
+	// ClaimName is the name of the existing PersistentVolumeClaim to mount
+	// +kubebuilder:validation:Required
+	ClaimName string `json:"claimName"`
+
+	// MountPath is the path inside the container where the volume will be mounted
+	// +kubebuilder:validation:Required
+	MountPath string `json:"mountPath"`
+
+	// SubPath within the volume from which the container's volume should be mounted
+	// +optional
+	SubPath string `json:"subPath,omitempty"`
+
+	// ReadOnly specifies whether the volume should be mounted as read-only
+	// +optional
+	ReadOnly bool `json:"readOnly,omitempty"`
+}
+
 type Volume struct {
 	PVCs    []corev1.PersistentVolumeClaim
 	Volumes []corev1.Volume
@@ -1687,6 +1718,106 @@ func AddSidecarPVCs(log logr.Logger, existing, sidecarPVCs []corev1.PersistentVo
 	return existing
 }
 
+// ExtraPVCVolumes generates Kubernetes volumes from ExtraPVC configurations.
+// Each ExtraPVC references an existing PersistentVolumeClaim by name.
+func ExtraPVCVolumes(log logr.Logger, extraPVCs []ExtraPVC) []corev1.Volume {
+	if len(extraPVCs) == 0 {
+		return nil
+	}
+
+	volumes := make([]corev1.Volume, 0, len(extraPVCs))
+	names := make(map[string]struct{}, len(extraPVCs))
+
+	for _, epvc := range extraPVCs {
+		if _, ok := names[epvc.Name]; ok {
+			log.Info("Duplicate extra PVC volume name, skipping", "volumeName", epvc.Name)
+			continue
+		}
+		names[epvc.Name] = struct{}{}
+
+		volumes = append(volumes, corev1.Volume{
+			Name: epvc.Name,
+			VolumeSource: corev1.VolumeSource{
+				PersistentVolumeClaim: &corev1.PersistentVolumeClaimVolumeSource{
+					ClaimName: epvc.ClaimName,
+					ReadOnly:  epvc.ReadOnly,
+				},
+			},
+		})
+	}
+
+	return volumes
+}
+
+// ExtraPVCVolumeMounts generates volume mounts from ExtraPVC configurations.
+func ExtraPVCVolumeMounts(ctx context.Context, extraPVCs []ExtraPVC) []corev1.VolumeMount {
+	logger := log.FromContext(ctx)
+
+	if len(extraPVCs) == 0 {
+		return nil
+	}
+
+	mounts := make([]corev1.VolumeMount, 0, len(extraPVCs))
+	names := make(map[string]struct{}, len(extraPVCs))
+
+	for _, epvc := range extraPVCs {
+		if _, ok := names[epvc.Name]; ok {
+			logger.Info("Duplicate extra PVC volume mount name, skipping", "volumeName", epvc.Name)
+			continue
+		}
+		names[epvc.Name] = struct{}{}
+
+		mounts = append(mounts, corev1.VolumeMount{
+			Name:      epvc.Name,
+			MountPath: epvc.MountPath,
+			SubPath:   epvc.SubPath,
+			ReadOnly:  epvc.ReadOnly,
+		})
+	}
+
+	return mounts
+}
+
+// ValidateExtraPVCs validates the extraPVCs configuration.
+func ValidateExtraPVCs(extraPVCs []ExtraPVC) error {
+	if len(extraPVCs) == 0 {
+		return nil
+	}
+
+	names := make(map[string]struct{}, len(extraPVCs))
+	claimNames := make(map[string]struct{}, len(extraPVCs))
+	mountPaths := make(map[string]struct{}, len(extraPVCs))
+
+	for _, epvc := range extraPVCs {
+		if epvc.Name == "" {
+			return errors.New("extraPVC: name cannot be empty")
+		}
+		if epvc.ClaimName == "" {
+			return errors.Errorf("extraPVC %s: claimName cannot be empty", epvc.Name)
+		}
+		if epvc.MountPath == "" {
+			return errors.Errorf("extraPVC %s: mountPath cannot be empty", epvc.Name)
+		}
+
+		if _, ok := names[epvc.Name]; ok {
+			return errors.Errorf("extraPVC: duplicate volume name %s", epvc.Name)
+		}
+		names[epvc.Name] = struct{}{}
+
+		if _, ok := mountPaths[epvc.MountPath]; ok {
+			return errors.Errorf("extraPVC %s: duplicate mount path %s", epvc.Name, epvc.MountPath)
+		}
+		mountPaths[epvc.MountPath] = struct{}{}
+
+		if _, ok := claimNames[epvc.ClaimName]; ok {
+			return errors.Errorf("extraPVC %s: duplicate claim name %s", epvc.Name, epvc.ClaimName)
+		}
+		claimNames[epvc.ClaimName] = struct{}{}
+	}
+
+	return nil
+}
+
 func (cr *PerconaXtraDBCluster) ProxySQLUnreadyServiceNamespacedName() types.NamespacedName {
 	return types.NamespacedName{
 		Name:      cr.Name + "-proxysql-unready",
diff --git a/pkg/apis/pxc/v1/zz_generated.deepcopy.go b/pkg/apis/pxc/v1/zz_generated.deepcopy.go
index ff13629659..d4d0fb2274 100644
--- a/pkg/apis/pxc/v1/zz_generated.deepcopy.go
+++ b/pkg/apis/pxc/v1/zz_generated.deepcopy.go
@@ -243,6 +243,21 @@ func (in *ComponentStatus) DeepCopy() *ComponentStatus {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *ExtraPVC) DeepCopyInto(out *ExtraPVC) {
+	*out = *in
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new ExtraPVC.
+func (in *ExtraPVC) DeepCopy() *ExtraPVC {
+	if in == nil {
+		return nil
+	}
+	out := new(ExtraPVC)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *HAProxyHealthCheckSpec) DeepCopyInto(out *HAProxyHealthCheckSpec) {
 	*out = *in
@@ -1225,6 +1240,11 @@ func (in *PodSpec) DeepCopyInto(out *PodSpec) {
 			(*in)[i].DeepCopyInto(&(*out)[i])
 		}
 	}
+	if in.ExtraPVCs != nil {
+		in, out := &in.ExtraPVCs, &out.ExtraPVCs
+		*out = make([]ExtraPVC, len(*in))
+		copy(*out, *in)
+	}
 	if in.RuntimeClassName != nil {
 		in, out := &in.RuntimeClassName, &out.RuntimeClassName
 		*out = new(string)
diff --git a/pkg/pxc/app/statefulset/node.go b/pkg/pxc/app/statefulset/node.go
index 37596b02e2..82be2ec62e 100644
--- a/pkg/pxc/app/statefulset/node.go
+++ b/pkg/pxc/app/statefulset/node.go
@@ -16,7 +16,7 @@ import (
 
 	api "github.com/percona/percona-xtradb-cluster-operator/pkg/apis/pxc/v1"
 	"github.com/percona/percona-xtradb-cluster-operator/pkg/naming"
-	app "github.com/percona/percona-xtradb-cluster-operator/pkg/pxc/app"
+	"github.com/percona/percona-xtradb-cluster-operator/pkg/pxc/app"
 	"github.com/percona/percona-xtradb-cluster-operator/pkg/pxc/app/config"
 	"github.com/percona/percona-xtradb-cluster-operator/pkg/pxc/users"
 )
@@ -270,6 +270,9 @@ func (c *Node) AppContainer(ctx context.Context, cl client.Client, spec *api.Pod
 
 	if cr.CompareVersionWith("1.19.0") >= 0 {
 		setLDPreloadEnv(ctx, cl, cr, &appc)
+
+		extraMounts := api.ExtraPVCVolumeMounts(ctx, spec.ExtraPVCs)
+		appc.VolumeMounts = append(appc.VolumeMounts, extraMounts...)
 	}
 
 	return appc, nil
diff --git a/pkg/pxc/statefulset.go b/pkg/pxc/statefulset.go
index 639ac56fd4..af33b3251c 100644
--- a/pkg/pxc/statefulset.go
+++ b/pkg/pxc/statefulset.go
@@ -96,6 +96,11 @@ func StatefulSet(
 	pod.Containers = api.AddSidecarContainers(log, pod.Containers, podSpec.Sidecars)
 	pod.Volumes = api.AddSidecarVolumes(log, pod.Volumes, podSpec.SidecarVolumes)
 
+	if cr.CompareVersionWith("1.19.0") >= 0 {
+		extraVolumes := api.ExtraPVCVolumes(log, podSpec.ExtraPVCs)
+		pod.Volumes = append(pod.Volumes, extraVolumes...)
+	}
+
 	ls := sfs.Labels()
 
 	customLabels := make(map[string]string, len(ls))

From cd0e5b3f60d71741ecf738a3175f9802bffe2874 Mon Sep 17 00:00:00 2001
From: George Kechagias <geo.kechagias@gmail.com>
Date: Mon, 1 Dec 2025 17:13:58 +0200
Subject: [PATCH 02/12] add e2e test

---
 e2e-tests/extra-pvc/compare/select-1.sql      |   1 +
 e2e-tests/extra-pvc/conf/extra-pvc.yml        |  69 ++++++
 .../conf/some-name-with-extra-pvcs.yml        |  64 ++++++
 e2e-tests/extra-pvc/conf/some-name.yml        |  59 +++++
 e2e-tests/extra-pvc/run                       | 201 ++++++++++++++++++
 5 files changed, 394 insertions(+)
 create mode 100644 e2e-tests/extra-pvc/compare/select-1.sql
 create mode 100644 e2e-tests/extra-pvc/conf/extra-pvc.yml
 create mode 100644 e2e-tests/extra-pvc/conf/some-name-with-extra-pvcs.yml
 create mode 100644 e2e-tests/extra-pvc/conf/some-name.yml
 create mode 100755 e2e-tests/extra-pvc/run

diff --git a/e2e-tests/extra-pvc/compare/select-1.sql b/e2e-tests/extra-pvc/compare/select-1.sql
new file mode 100644
index 0000000000..8e738f4cf2
--- /dev/null
+++ b/e2e-tests/extra-pvc/compare/select-1.sql
@@ -0,0 +1 @@
+100500
diff --git a/e2e-tests/extra-pvc/conf/extra-pvc.yml b/e2e-tests/extra-pvc/conf/extra-pvc.yml
new file mode 100644
index 0000000000..1096849566
--- /dev/null
+++ b/e2e-tests/extra-pvc/conf/extra-pvc.yml
@@ -0,0 +1,69 @@
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: extra-storage-source
+spec:
+  accessModes:
+    - ReadWriteOnce
+  resources:
+    requests:
+      storage: 1Gi
+---
+apiVersion: v1
+kind: Pod
+metadata:
+  name: pvc-populator
+spec:
+  containers:
+  - name: populator
+    image: busybox
+    command: ['sh', '-c', 'echo "Initial data" > /var/lib/mysql-extra/test-data.csv']
+    volumeMounts:
+    - name: data
+      mountPath: /data
+  volumes:
+  - name: data
+    persistentVolumeClaim:
+      claimName: extra-storage-source
+---
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: extra-storage-0
+spec:
+  accessModes:
+    - ReadOnlyMany
+  dataSource:
+    name: extra-storage-source
+    kind: PersistentVolumeClaim
+  resources:
+    requests:
+      storage: 1Gi
+---
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: extra-storage-1
+spec:
+  accessModes:
+    - ReadOnlyMany
+  dataSource:
+    name: extra-storage-source
+    kind: PersistentVolumeClaim
+  resources:
+    requests:
+      storage: 1Gi
+---
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: extra-storage-2
+spec:
+  accessModes:
+    - ReadOnlyMany
+  dataSource:
+    name: extra-storage-source
+    kind: PersistentVolumeClaim
+  resources:
+    requests:
+      storage: 1Gi
diff --git a/e2e-tests/extra-pvc/conf/some-name-with-extra-pvcs.yml b/e2e-tests/extra-pvc/conf/some-name-with-extra-pvcs.yml
new file mode 100644
index 0000000000..970f6534fc
--- /dev/null
+++ b/e2e-tests/extra-pvc/conf/some-name-with-extra-pvcs.yml
@@ -0,0 +1,64 @@
+apiVersion: pxc.percona.com/v1
+kind: PerconaXtraDBCluster
+metadata:
+  name: some-name
+  finalizers:
+    - percona.com/delete-pxc-pods-in-order
+spec:
+  secretsName: my-cluster-secrets
+  vaultSecretName: some-name-vault
+  pause: false
+  pxc:
+    size: 3
+    image: -pxc
+    resources:
+      requests:
+        memory: 0.1G
+        cpu: 100m
+      limits:
+        memory: "2G"
+        cpu: "1"
+    volumeSpec:
+      persistentVolumeClaim:
+        resources:
+          requests:
+            storage: 2Gi
+    extraPVCs:
+      - name: extra-data-volume
+        claimName: extra-storage-0
+        mountPath: /var/lib/mysql-extra
+        readOnly: false
+    affinity:
+      antiAffinityTopologyKey: "kubernetes.io/hostname"
+  haproxy:
+    enabled: true
+    size: 2
+    image: -haproxy
+    resources:
+      requests:
+        memory: 0.1G
+        cpu: 100m
+      limits:
+        memory: 1G
+        cpu: 700m
+    affinity:
+      antiAffinityTopologyKey: "kubernetes.io/hostname"
+  logcollector:
+    enabled: false
+    image: -logcollector
+  pmm:
+    enabled: false
+    image: perconalab/pmm-client:1.17.1
+    serverHost: monitoring-service
+    serverUser: pmm
+  backup:
+    image: -backup
+    storages:
+      pvc:
+        type: filesystem
+        volume:
+          persistentVolumeClaim:
+            accessModes: [ "ReadWriteOnce" ]
+            resources:
+              requests:
+                storage: 1G
\ No newline at end of file
diff --git a/e2e-tests/extra-pvc/conf/some-name.yml b/e2e-tests/extra-pvc/conf/some-name.yml
new file mode 100644
index 0000000000..9b6ab5419f
--- /dev/null
+++ b/e2e-tests/extra-pvc/conf/some-name.yml
@@ -0,0 +1,59 @@
+apiVersion: pxc.percona.com/v1
+kind: PerconaXtraDBCluster
+metadata:
+  name: some-name
+  finalizers:
+    - percona.com/delete-pxc-pods-in-order
+spec:
+  secretsName: my-cluster-secrets
+  vaultSecretName: some-name-vault
+  pause: false
+  pxc:
+    size: 3
+    image: -pxc
+    resources:
+      requests:
+        memory: 0.1G
+        cpu: 100m
+      limits:
+        memory: "2G"
+        cpu: "1"
+    volumeSpec:
+      persistentVolumeClaim:
+        resources:
+          requests:
+            storage: 2Gi
+    affinity:
+      antiAffinityTopologyKey: "kubernetes.io/hostname"
+  haproxy:
+    enabled: true
+    size: 2
+    image: -haproxy
+    resources:
+      requests:
+        memory: 0.1G
+        cpu: 100m
+      limits:
+        memory: 1G
+        cpu: 700m
+    affinity:
+      antiAffinityTopologyKey: "kubernetes.io/hostname"
+  logcollector:
+    enabled: false
+    image: -logcollector
+  pmm:
+    enabled: false
+    image: perconalab/pmm-client:1.17.1
+    serverHost: monitoring-service
+    serverUser: pmm
+  backup:
+    image: -backup
+    storages:
+      pvc:
+        type: filesystem
+        volume:
+          persistentVolumeClaim:
+            accessModes: [ "ReadWriteOnce" ]
+            resources:
+              requests:
+                storage: 1G
\ No newline at end of file
diff --git a/e2e-tests/extra-pvc/run b/e2e-tests/extra-pvc/run
new file mode 100755
index 0000000000..c70b8509f0
--- /dev/null
+++ b/e2e-tests/extra-pvc/run
@@ -0,0 +1,201 @@
+#!/bin/bash
+
+set -o errexit
+
+test_dir=$(realpath $(dirname $0))
+. ${test_dir}/../functions
+
+  function create_extra_pvcs() {
+      local ns=$1
+
+      echo "Creating extra PVCs in namespace ${ns}"
+      kubectl_bin apply -f ${test_dir}/conf/extra-pvc.yml -n ${ns}
+
+      echo "Waiting for source PVC to be bound"
+      kubectl_bin wait --for=jsonpath='{.status.phase}'=Bound pvc/extra-storage-source -n ${ns} --timeout=60s
+
+      echo "Waiting for populator pod to be ready"
+      kubectl_bin wait --for=condition=Ready pod/pvc-populator -n ${ns} --timeout=60s
+  }
+
+function verify_extra_pvc_mounted() {
+	local pod=$1
+	local mount_path=$2
+
+	echo "Verifying extra PVC is mounted in pod ${pod} at ${mount_path}"
+
+	if ! kubectl_bin exec ${pod} -c pxc -- test -d ${mount_path}; then
+		echo "Mount path ${mount_path} does not exist in pod ${pod}"
+		exit 1
+	fi
+
+	echo "Mount path ${mount_path} exists in pod ${pod}"
+}
+
+function verify_extra_pvc_in_statefulset() {
+	local cluster=$1
+	local expected_claim_name=$2
+	local expected_mount_path=$3
+
+	echo "Verifying extra PVC configuration in StatefulSet ${cluster}-pxc"
+
+	local volume_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json | \
+		jq --arg claim "${expected_claim_name}" '.spec.template.spec.volumes[] | select(.persistentVolumeClaim.claimName == $claim) | .name' -r)
+
+	if [[ -z "$volume_exists" ]]; then
+		echo "Volume with claimName ${expected_claim_name} not found in StatefulSet"
+		kubectl_bin get statefulset ${cluster}-pxc -o yaml
+		exit 1
+	fi
+
+	echo "Volume ${volume_exists} with claimName ${expected_claim_name} found in StatefulSet"
+
+	local mount_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json | \
+		jq --arg path "${expected_mount_path}" '.spec.template.spec.containers[] | select(.name == "pxc") | .volumeMounts[] | select(.mountPath == $path) | .name' -r)
+
+	if [[ -z "$mount_exists" ]]; then
+		echo "Volume mount with mountPath ${expected_mount_path} not found in pxc container"
+		kubectl_bin get statefulset ${cluster}-pxc -o yaml
+		exit 1
+	fi
+
+	echo "Volume mount ${mount_exists} with mountPath ${expected_mount_path} found in pxc container"
+}
+
+function patch_cluster_add_extra_pvcs() {
+	local cluster=$1
+
+	echo "Patching cluster ${cluster} to add extraPVCs"
+
+	kubectl_bin patch pxc ${cluster} --type=json -p='[
+		{
+			"op": "add",
+			"path": "/spec/pxc/extraPVCs",
+			"value": [
+				{
+					"name": "extra-data-volume",
+					"claimName": "extra-storage-0",
+					"mountPath": "/var/lib/mysql-extra",
+					"readOnly": true
+				}
+			]
+		}
+	]'
+}
+
+function patch_cluster_remove_extra_pvcs() {
+	local cluster=$1
+
+	echo "Patching cluster ${cluster} to remove extraPVCs"
+
+	kubectl_bin patch pxc ${cluster} --type=json -p='[
+		{
+			"op": "remove",
+			"path": "/spec/pxc/extraPVCs"
+		}
+	]'
+}
+
+function patch_cluster_add_multiple_extra_pvcs() {
+	local cluster=$1
+
+	echo "Patching cluster ${cluster} to add multiple extraPVCs"
+
+	kubectl_bin patch pxc ${cluster} --type=json -p='[
+		{
+			"op": "replace",
+			"path": "/spec/pxc/extraPVCs",
+			"value": [
+				{
+					"name": "extra-data-volume-1",
+					"claimName": "extra-storage-1",
+					"mountPath": "/var/lib/mysql-extra-1",
+					"readOnly": true
+				},
+				{
+					"name": "extra-data-volume-2",
+					"claimName": "extra-storage-2",
+					"mountPath": "/var/lib/mysql-extra-2",
+					"readOnly": true
+				}
+			]
+		}
+	]'
+}
+
+set_debug
+
+create_infra ${namespace}
+
+desc 'create extra PVCs'
+create_extra_pvcs ${namespace}
+
+desc 'create PXC cluster without extra PVCs'
+cluster="some-name"
+spinup_pxc "${cluster}" "$test_dir/conf/$cluster.yml" "3" "10" "${conf_dir}/secrets.yml"
+
+desc 'verify cluster is running without extra PVCs'
+wait_cluster_consistency "$cluster" 3 2
+
+desc 'test adding extra PVC to running cluster'
+patch_cluster_add_extra_pvcs "${cluster}"
+wait_cluster_consistency "$cluster" 3 2
+sleep 10
+
+desc 'verify extra PVC is configured in StatefulSet'
+verify_extra_pvc_in_statefulset "${cluster}" "extra-storage-0" "/var/lib/mysql-extra"
+
+desc 'verify extra PVC is mounted in all PXC pods'
+for i in 0 1 2; do
+	verify_extra_pvc_mounted "${cluster}-pxc-${i}" "/var/lib/mysql-extra"
+done
+
+desc 'test adding multiple extra PVCs'
+patch_cluster_add_multiple_extra_pvcs "${cluster}"
+wait_cluster_consistency "$cluster" 3 2
+sleep 10
+
+desc 'verify multiple extra PVCs are mounted'
+for i in 0 1 2; do
+	verify_extra_pvc_mounted "${cluster}-pxc-${i}" "/var/lib/mysql-extra-1"
+	if kubectl_bin exec ${cluster}-pxc-${i} -c pxc -- touch /var/lib/mysql-extra-2/test-write 2>/dev/null; then
+		echo "Read-only mount /var/lib/mysql-extra-2 is writable in pod ${cluster}-pxc-${i}"
+		exit 1
+	fi
+	echo "Read-only mount /var/lib/mysql-extra-2 is properly read-only in pod ${cluster}-pxc-${i}"
+done
+
+desc 'test removing extra PVCs from cluster'
+patch_cluster_remove_extra_pvcs "${cluster}"
+wait_cluster_consistency "$cluster" 3 2
+sleep 10
+
+desc 'verify extra PVCs are removed from StatefulSet'
+for claim in extra-storage-1 extra-storage-2; do
+	volume_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json | \
+		jq --arg claim "${claim}" '.spec.template.spec.volumes[] | select(.persistentVolumeClaim.claimName == $claim) | .name' -r)
+
+	if [[ -n "$volume_exists" ]]; then
+		echo "Volume with claimName ${claim} still exists in StatefulSet after removal"
+		exit 1
+	fi
+done
+echo "Extra PVCs successfully removed from StatefulSet"
+
+desc 'test creating cluster with extra PVCs from start'
+cluster2="some-name-2"
+kubectl_bin apply -f ${test_dir}/conf/some-name-with-extra-pvcs.yml
+wait_cluster_consistency "$cluster2" 3 2
+
+desc 'verify extra PVC is configured in new cluster'
+verify_extra_pvc_in_statefulset "${cluster2}" "extra-storage-0" "/var/lib/mysql-extra"
+
+for i in 0 1 2; do
+	verify_extra_pvc_mounted "${cluster2}-pxc-${i}" "/var/lib/mysql-extra"
+done
+
+desc 'cleanup second cluster'
+kubectl_bin delete pxc ${cluster2}
+
+destroy "${namespace}"
+desc "test passed"
\ No newline at end of file

From c912e14728d599b19004d659a5af5cbde4079ff0 Mon Sep 17 00:00:00 2001
From: George Kechagias <geo.kechagias@gmail.com>
Date: Tue, 2 Dec 2025 10:51:13 +0200
Subject: [PATCH 03/12] fix linting

---
 e2e-tests/extra-pvc/run | 38 +++++++++++++++++++-------------------
 1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/e2e-tests/extra-pvc/run b/e2e-tests/extra-pvc/run
index c70b8509f0..225889ad40 100755
--- a/e2e-tests/extra-pvc/run
+++ b/e2e-tests/extra-pvc/run
@@ -5,18 +5,18 @@ set -o errexit
 test_dir=$(realpath $(dirname $0))
 . ${test_dir}/../functions
 
-  function create_extra_pvcs() {
-      local ns=$1
+function create_extra_pvcs() {
+	local ns=$1
 
-      echo "Creating extra PVCs in namespace ${ns}"
-      kubectl_bin apply -f ${test_dir}/conf/extra-pvc.yml -n ${ns}
+	echo "Creating extra PVCs in namespace ${ns}"
+	kubectl_bin apply -f ${test_dir}/conf/extra-pvc.yml -n ${ns}
 
-      echo "Waiting for source PVC to be bound"
-      kubectl_bin wait --for=jsonpath='{.status.phase}'=Bound pvc/extra-storage-source -n ${ns} --timeout=60s
+	echo "Waiting for source PVC to be bound"
+	kubectl_bin wait --for=jsonpath='{.status.phase}'=Bound pvc/extra-storage-source -n ${ns} --timeout=60s
 
-      echo "Waiting for populator pod to be ready"
-      kubectl_bin wait --for=condition=Ready pod/pvc-populator -n ${ns} --timeout=60s
-  }
+	echo "Waiting for populator pod to be ready"
+	kubectl_bin wait --for=condition=Ready pod/pvc-populator -n ${ns} --timeout=60s
+}
 
 function verify_extra_pvc_mounted() {
 	local pod=$1
@@ -39,10 +39,10 @@ function verify_extra_pvc_in_statefulset() {
 
 	echo "Verifying extra PVC configuration in StatefulSet ${cluster}-pxc"
 
-	local volume_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json | \
-		jq --arg claim "${expected_claim_name}" '.spec.template.spec.volumes[] | select(.persistentVolumeClaim.claimName == $claim) | .name' -r)
+	local volume_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json \
+		| jq --arg claim "${expected_claim_name}" '.spec.template.spec.volumes[] | select(.persistentVolumeClaim.claimName == $claim) | .name' -r)
 
-	if [[ -z "$volume_exists" ]]; then
+	if [[ -z $volume_exists ]]; then
 		echo "Volume with claimName ${expected_claim_name} not found in StatefulSet"
 		kubectl_bin get statefulset ${cluster}-pxc -o yaml
 		exit 1
@@ -50,10 +50,10 @@ function verify_extra_pvc_in_statefulset() {
 
 	echo "Volume ${volume_exists} with claimName ${expected_claim_name} found in StatefulSet"
 
-	local mount_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json | \
-		jq --arg path "${expected_mount_path}" '.spec.template.spec.containers[] | select(.name == "pxc") | .volumeMounts[] | select(.mountPath == $path) | .name' -r)
+	local mount_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json \
+		| jq --arg path "${expected_mount_path}" '.spec.template.spec.containers[] | select(.name == "pxc") | .volumeMounts[] | select(.mountPath == $path) | .name' -r)
 
-	if [[ -z "$mount_exists" ]]; then
+	if [[ -z $mount_exists ]]; then
 		echo "Volume mount with mountPath ${expected_mount_path} not found in pxc container"
 		kubectl_bin get statefulset ${cluster}-pxc -o yaml
 		exit 1
@@ -172,10 +172,10 @@ sleep 10
 
 desc 'verify extra PVCs are removed from StatefulSet'
 for claim in extra-storage-1 extra-storage-2; do
-	volume_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json | \
-		jq --arg claim "${claim}" '.spec.template.spec.volumes[] | select(.persistentVolumeClaim.claimName == $claim) | .name' -r)
+	volume_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json \
+		| jq --arg claim "${claim}" '.spec.template.spec.volumes[] | select(.persistentVolumeClaim.claimName == $claim) | .name' -r)
 
-	if [[ -n "$volume_exists" ]]; then
+	if [[ -n $volume_exists ]]; then
 		echo "Volume with claimName ${claim} still exists in StatefulSet after removal"
 		exit 1
 	fi
@@ -198,4 +198,4 @@ desc 'cleanup second cluster'
 kubectl_bin delete pxc ${cluster2}
 
 destroy "${namespace}"
-desc "test passed"
\ No newline at end of file
+desc "test passed"

From 8fd181b941a45a562a187d5a9c65e5690c7614c8 Mon Sep 17 00:00:00 2001
From: George Kechagias <geo.kechagias@gmail.com>
Date: Tue, 2 Dec 2025 11:20:24 +0200
Subject: [PATCH 04/12] add unit tests

---
 pkg/apis/pxc/v1/pxc_types.go         |   6 +-
 pkg/apis/pxc/v1/pxc_types_test.go    | 237 +++++++++++++++++++++++++++
 pkg/pxc/app/statefulset/node_test.go |  46 ++++++
 3 files changed, 286 insertions(+), 3 deletions(-)

diff --git a/pkg/apis/pxc/v1/pxc_types.go b/pkg/apis/pxc/v1/pxc_types.go
index 2ac147a82f..51dd3ba00b 100644
--- a/pkg/apis/pxc/v1/pxc_types.go
+++ b/pkg/apis/pxc/v1/pxc_types.go
@@ -532,7 +532,7 @@ func (cr *PerconaXtraDBCluster) Validate() error {
 	}
 
 	if c.PXC != nil && len(c.PXC.ExtraPVCs) > 0 {
-		if err := ValidateExtraPVCs(c.PXC.ExtraPVCs); err != nil {
+		if err := validateExtraPVCs(c.PXC.ExtraPVCs); err != nil {
 			return errors.Wrap(err, "PXC: validate extraPVCs")
 		}
 	}
@@ -1778,8 +1778,8 @@ func ExtraPVCVolumeMounts(ctx context.Context, extraPVCs []ExtraPVC) []corev1.Vo
 	return mounts
 }
 
-// ValidateExtraPVCs validates the extraPVCs configuration.
-func ValidateExtraPVCs(extraPVCs []ExtraPVC) error {
+// validateExtraPVCs validates the extraPVCs configuration.
+func validateExtraPVCs(extraPVCs []ExtraPVC) error {
 	if len(extraPVCs) == 0 {
 		return nil
 	}
diff --git a/pkg/apis/pxc/v1/pxc_types_test.go b/pkg/apis/pxc/v1/pxc_types_test.go
index 99ce7a9ba4..c68c0671b3 100644
--- a/pkg/apis/pxc/v1/pxc_types_test.go
+++ b/pkg/apis/pxc/v1/pxc_types_test.go
@@ -261,3 +261,240 @@ func TestCheckNSetDefaults(t *testing.T) {
 		assert.EqualError(t, cr.CheckNSetDefaults(nil, logf.FromContext(ctx)), ".spec.tls.certValidityDuration shouldn't be smaller than 1 hours")
 	})
 }
+
+func TestExtraPVCVolumeMounts(t *testing.T) {
+	ctx := t.Context()
+
+	tests := map[string]struct {
+		extraPVCs []ExtraPVC
+		expected  []corev1.VolumeMount
+	}{
+		"nil extra PVCs": {
+			extraPVCs: nil,
+			expected:  nil,
+		},
+		"empty extra PVCs": {
+			extraPVCs: []ExtraPVC{},
+			expected:  nil,
+		},
+		"single extra PVC without subPath and readOnly": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-0",
+					MountPath: "/var/lib/mysql-extra",
+				},
+			},
+			expected: []corev1.VolumeMount{
+				{
+					Name:      "extra-data",
+					MountPath: "/var/lib/mysql-extra",
+					SubPath:   "",
+					ReadOnly:  false,
+				},
+			},
+		},
+		"single extra PVC with subPath and readOnly": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "backup-volume",
+					ClaimName: "backup-storage-0",
+					MountPath: "/backups",
+					SubPath:   "mysql",
+					ReadOnly:  true,
+				},
+			},
+			expected: []corev1.VolumeMount{
+				{
+					Name:      "backup-volume",
+					MountPath: "/backups",
+					SubPath:   "mysql",
+					ReadOnly:  true,
+				},
+			},
+		},
+		"multiple extra PVCs": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-0",
+					MountPath: "/var/lib/mysql-extra",
+				},
+				{
+					Name:      "backup-volume",
+					ClaimName: "backup-storage-0",
+					MountPath: "/backups",
+					SubPath:   "mysql",
+					ReadOnly:  true,
+				},
+			},
+			expected: []corev1.VolumeMount{
+				{
+					Name:      "extra-data",
+					MountPath: "/var/lib/mysql-extra",
+					SubPath:   "",
+					ReadOnly:  false,
+				},
+				{
+					Name:      "backup-volume",
+					MountPath: "/backups",
+					SubPath:   "mysql",
+					ReadOnly:  true,
+				},
+			},
+		},
+		"duplicate names - only first should be included": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-0",
+					MountPath: "/var/lib/mysql-extra",
+				},
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-1",
+					MountPath: "/var/lib/mysql-extra2",
+				},
+			},
+			expected: []corev1.VolumeMount{
+				{
+					Name:      "extra-data",
+					MountPath: "/var/lib/mysql-extra",
+					SubPath:   "",
+					ReadOnly:  false,
+				},
+			},
+		},
+	}
+
+	for name, tc := range tests {
+		t.Run(name, func(t *testing.T) {
+			actual := ExtraPVCVolumeMounts(ctx, tc.extraPVCs)
+			assert.Equal(t, tc.expected, actual)
+		})
+	}
+}
+
+func TestValidateExtraPVCs(t *testing.T) {
+	tests := map[string]struct {
+		extraPVCs []ExtraPVC
+		errMsg    string
+	}{
+		"nil extra PVCs": {
+			extraPVCs: nil,
+		},
+		"empty extra PVCs": {
+			extraPVCs: []ExtraPVC{},
+		},
+		"valid single extra PVC": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-0",
+					MountPath: "/var/lib/mysql-extra",
+				},
+			},
+		},
+		"valid multiple extra PVCs": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-0",
+					MountPath: "/var/lib/mysql-extra",
+				},
+				{
+					Name:      "backup-volume",
+					ClaimName: "backup-storage-0",
+					MountPath: "/backups",
+				},
+			},
+		},
+		"empty name": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "",
+					ClaimName: "extra-storage-0",
+					MountPath: "/var/lib/mysql-extra",
+				},
+			},
+			errMsg: "extraPVC: name cannot be empty",
+		},
+		"empty claim name": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "extra-data",
+					ClaimName: "",
+					MountPath: "/var/lib/mysql-extra",
+				},
+			},
+			errMsg: "extraPVC extra-data: claimName cannot be empty",
+		},
+		"empty mount path": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-0",
+					MountPath: "",
+				},
+			},
+			errMsg: "extraPVC extra-data: mountPath cannot be empty",
+		},
+		"duplicate volume name": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-0",
+					MountPath: "/var/lib/mysql-extra",
+				},
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-1",
+					MountPath: "/var/lib/mysql-extra2",
+				},
+			},
+			errMsg: "extraPVC: duplicate volume name extra-data",
+		},
+		"duplicate mount path": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-0",
+					MountPath: "/var/lib/mysql-extra",
+				},
+				{
+					Name:      "backup-volume",
+					ClaimName: "backup-storage-0",
+					MountPath: "/var/lib/mysql-extra",
+				},
+			},
+			errMsg: "extraPVC backup-volume: duplicate mount path /var/lib/mysql-extra",
+		},
+		"duplicate claim name": {
+			extraPVCs: []ExtraPVC{
+				{
+					Name:      "extra-data",
+					ClaimName: "extra-storage-0",
+					MountPath: "/var/lib/mysql-extra",
+				},
+				{
+					Name:      "backup-volume",
+					ClaimName: "extra-storage-0",
+					MountPath: "/backups",
+				},
+			},
+			errMsg: "extraPVC backup-volume: duplicate claim name extra-storage-0",
+		},
+	}
+
+	for name, tc := range tests {
+		t.Run(name, func(t *testing.T) {
+			err := validateExtraPVCs(tc.extraPVCs)
+			if tc.errMsg != "" {
+				assert.Error(t, err)
+				assert.Contains(t, err.Error(), tc.errMsg)
+			} else {
+				assert.NoError(t, err)
+			}
+		})
+	}
+}
diff --git a/pkg/pxc/app/statefulset/node_test.go b/pkg/pxc/app/statefulset/node_test.go
index 08ad5c09ac..8ba331f883 100644
--- a/pkg/pxc/app/statefulset/node_test.go
+++ b/pkg/pxc/app/statefulset/node_test.go
@@ -165,6 +165,52 @@ func TestAppContainer(t *testing.T) {
 				return c
 			},
 		},
+		"container construction with extra pvcs": {
+			spec: api.PerconaXtraDBClusterSpec{
+				CRVersion: version.Version(),
+				PXC: &api.PXCSpec{
+					PodSpec: &api.PodSpec{
+						Image:           "test-image",
+						ImagePullPolicy: corev1.PullIfNotPresent,
+						LivenessProbes: corev1.Probe{
+							TimeoutSeconds: 5,
+						},
+						ReadinessProbes: corev1.Probe{
+							TimeoutSeconds: 15,
+						},
+						EnvVarsSecretName: "test-secret",
+						ExtraPVCs: []api.ExtraPVC{
+							{
+								Name:      "extra-data-volume",
+								ClaimName: "extra-storage-0",
+								MountPath: "/var/lib/mysql-extra",
+							},
+							{
+								Name:      "backup-volume",
+								ClaimName: "backup-storage-0",
+								MountPath: "/backups",
+								SubPath:   "mysql",
+							},
+						},
+					},
+				},
+			},
+			expectedContainer: func() corev1.Container {
+				c := defaultExpectedContainer()
+				c.VolumeMounts = append(c.VolumeMounts,
+					corev1.VolumeMount{
+						Name:      "extra-data-volume",
+						MountPath: "/var/lib/mysql-extra",
+					},
+					corev1.VolumeMount{
+						Name:      "backup-volume",
+						MountPath: "/backups",
+						SubPath:   "mysql",
+					},
+				)
+				return c
+			},
+		},
 	}
 
 	for name, tt := range tests {

From b967e24ec0b3f4df7ec8603927fb9f2f1bbd73f3 Mon Sep 17 00:00:00 2001
From: George Kechagias <geo.kechagias@gmail.com>
Date: Tue, 2 Dec 2025 12:38:56 +0200
Subject: [PATCH 05/12] update e2e test

---
 e2e-tests/extra-pvc/conf/extra-pvc.yml | 2 +-
 e2e-tests/run-distro.csv               | 1 +
 e2e-tests/run-pr.csv                   | 1 +
 e2e-tests/run-release.csv              | 1 +
 4 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/e2e-tests/extra-pvc/conf/extra-pvc.yml b/e2e-tests/extra-pvc/conf/extra-pvc.yml
index 1096849566..d478082ff5 100644
--- a/e2e-tests/extra-pvc/conf/extra-pvc.yml
+++ b/e2e-tests/extra-pvc/conf/extra-pvc.yml
@@ -17,7 +17,7 @@ spec:
   containers:
   - name: populator
     image: busybox
-    command: ['sh', '-c', 'echo "Initial data" > /var/lib/mysql-extra/test-data.csv']
+    command: ['sh', '-c', 'echo "Initial data" > /data/test-data.txt && sleep infinity']
     volumeMounts:
     - name: data
       mountPath: /data
diff --git a/e2e-tests/run-distro.csv b/e2e-tests/run-distro.csv
index 1bc0a0dec5..471022002e 100644
--- a/e2e-tests/run-distro.csv
+++ b/e2e-tests/run-distro.csv
@@ -3,6 +3,7 @@ auto-tuning
 default-cr
 demand-backup-encrypted-with-tls
 custom-users
+extra-pvc
 haproxy
 init-deploy
 one-pod
diff --git a/e2e-tests/run-pr.csv b/e2e-tests/run-pr.csv
index 59d3d08a83..9b17ae1927 100644
--- a/e2e-tests/run-pr.csv
+++ b/e2e-tests/run-pr.csv
@@ -9,6 +9,7 @@ demand-backup,8.0
 demand-backup-flow-control,8.0
 demand-backup-parallel,8.0
 demand-backup-without-passwords,8.0
+extra-pvc
 haproxy,5.7
 haproxy,8.0
 init-deploy,5.7
diff --git a/e2e-tests/run-release.csv b/e2e-tests/run-release.csv
index 14b265aa1a..0cbb1f74a9 100644
--- a/e2e-tests/run-release.csv
+++ b/e2e-tests/run-release.csv
@@ -11,6 +11,7 @@ demand-backup-parallel
 demand-backup-cloud
 demand-backup-encrypted-with-tls
 demand-backup-without-passwords
+extra-pvc
 haproxy
 init-deploy
 limits

From 6a9242f0a42904ad1e1686c839dde7f7f026b5ab Mon Sep 17 00:00:00 2001
From: Viacheslav Sarzhan <slava.sarzhan@percona.com>
Date: Tue, 2 Dec 2025 16:51:21 +0200
Subject: [PATCH 06/12] fix tests

---
 e2e-tests/run-pr.csv | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/e2e-tests/run-pr.csv b/e2e-tests/run-pr.csv
index 9b17ae1927..073908cafe 100644
--- a/e2e-tests/run-pr.csv
+++ b/e2e-tests/run-pr.csv
@@ -9,7 +9,7 @@ demand-backup,8.0
 demand-backup-flow-control,8.0
 demand-backup-parallel,8.0
 demand-backup-without-passwords,8.0
-extra-pvc
+extra-pv,8.0
 haproxy,5.7
 haproxy,8.0
 init-deploy,5.7

From c1106f6eb85ffcd758336659ce2db25a1f9f3a0c Mon Sep 17 00:00:00 2001
From: Viacheslav Sarzhan <slava.sarzhan@percona.com>
Date: Tue, 2 Dec 2025 17:27:47 +0200
Subject: [PATCH 07/12] Update run-pr.csv

---
 e2e-tests/run-pr.csv | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/e2e-tests/run-pr.csv b/e2e-tests/run-pr.csv
index 073908cafe..c87dad18cd 100644
--- a/e2e-tests/run-pr.csv
+++ b/e2e-tests/run-pr.csv
@@ -9,7 +9,7 @@ demand-backup,8.0
 demand-backup-flow-control,8.0
 demand-backup-parallel,8.0
 demand-backup-without-passwords,8.0
-extra-pv,8.0
+extra-pvc,8.0
 haproxy,5.7
 haproxy,8.0
 init-deploy,5.7

From 56c95ac004be7dac20ac5a59fa4f4ed84cbe5d4c Mon Sep 17 00:00:00 2001
From: Viacheslav Sarzhan <slava.sarzhan@percona.com>
Date: Wed, 3 Dec 2025 22:44:09 +0200
Subject: [PATCH 08/12] K8SPXC-1688 fix extra-pvc test

---
 e2e-tests/extra-pvc/conf/some-name-with-extra-pvcs.yml | 5 +++--
 e2e-tests/extra-pvc/conf/some-name.yml                 | 3 ++-
 e2e-tests/extra-pvc/run                                | 7 +++++--
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/e2e-tests/extra-pvc/conf/some-name-with-extra-pvcs.yml b/e2e-tests/extra-pvc/conf/some-name-with-extra-pvcs.yml
index 970f6534fc..e18ef7109b 100644
--- a/e2e-tests/extra-pvc/conf/some-name-with-extra-pvcs.yml
+++ b/e2e-tests/extra-pvc/conf/some-name-with-extra-pvcs.yml
@@ -1,9 +1,10 @@
 apiVersion: pxc.percona.com/v1
 kind: PerconaXtraDBCluster
 metadata:
-  name: some-name
+  name: some-name-2
   finalizers:
     - percona.com/delete-pxc-pods-in-order
+    - percona.com/delete-pxc-pvc
 spec:
   secretsName: my-cluster-secrets
   vaultSecretName: some-name-vault
@@ -61,4 +62,4 @@ spec:
             accessModes: [ "ReadWriteOnce" ]
             resources:
               requests:
-                storage: 1G
\ No newline at end of file
+                storage: 1G
diff --git a/e2e-tests/extra-pvc/conf/some-name.yml b/e2e-tests/extra-pvc/conf/some-name.yml
index 9b6ab5419f..c46e4de06f 100644
--- a/e2e-tests/extra-pvc/conf/some-name.yml
+++ b/e2e-tests/extra-pvc/conf/some-name.yml
@@ -4,6 +4,7 @@ metadata:
   name: some-name
   finalizers:
     - percona.com/delete-pxc-pods-in-order
+    - percona.com/delete-pxc-pvc
 spec:
   secretsName: my-cluster-secrets
   vaultSecretName: some-name-vault
@@ -56,4 +57,4 @@ spec:
             accessModes: [ "ReadWriteOnce" ]
             resources:
               requests:
-                storage: 1G
\ No newline at end of file
+                storage: 1G
diff --git a/e2e-tests/extra-pvc/run b/e2e-tests/extra-pvc/run
index 225889ad40..4f5e745e1b 100755
--- a/e2e-tests/extra-pvc/run
+++ b/e2e-tests/extra-pvc/run
@@ -182,9 +182,12 @@ for claim in extra-storage-1 extra-storage-2; do
 done
 echo "Extra PVCs successfully removed from StatefulSet"
 
-desc 'test creating cluster with extra PVCs from start'
 cluster2="some-name-2"
-kubectl_bin apply -f ${test_dir}/conf/some-name-with-extra-pvcs.yml
+desc "Deleting ${cluster} and recreating PXC cluster ${cluster1}"
+kubectl_bin delete pxc ${cluster}
+
+desc 'test creating cluster with extra PVCs from start'
+spinup_pxc "${cluster2}" "$test_dir/conf/some-name-with-extra-pvcs.yml" "3" "10"
 wait_cluster_consistency "$cluster2" 3 2
 
 desc 'verify extra PVC is configured in new cluster'

From 3dbb4355bb6de3ed37f86b3d5238f8cab8595abc Mon Sep 17 00:00:00 2001
From: George Kechagias <geo.kechagias@gmail.com>
Date: Thu, 4 Dec 2025 10:28:14 +0100
Subject: [PATCH 09/12] fix wiring for proxysql and haproxy for extra pvc,
 update unit test

---
 pkg/pxc/app/statefulset/haproxy.go       |   7 +-
 pkg/pxc/app/statefulset/haproxy_test.go  | 164 +++++++++++++++++++++++
 pkg/pxc/app/statefulset/proxysql.go      |   5 +-
 pkg/pxc/app/statefulset/proxysql_test.go |  43 ++++++
 4 files changed, 217 insertions(+), 2 deletions(-)

diff --git a/pkg/pxc/app/statefulset/haproxy.go b/pkg/pxc/app/statefulset/haproxy.go
index c6d4c444c2..966e1803d7 100644
--- a/pkg/pxc/app/statefulset/haproxy.go
+++ b/pkg/pxc/app/statefulset/haproxy.go
@@ -46,7 +46,7 @@ func (c *HAProxy) InitContainers(cr *api.PerconaXtraDBCluster, initImageName str
 	return inits
 }
 
-func (c *HAProxy) AppContainer(_ context.Context, _ client.Client, spec *api.PodSpec, secrets string, cr *api.PerconaXtraDBCluster,
+func (c *HAProxy) AppContainer(ctx context.Context, _ client.Client, spec *api.PodSpec, secrets string, cr *api.PerconaXtraDBCluster,
 	_ []corev1.Volume,
 ) (corev1.Container, error) {
 	appc := corev1.Container{
@@ -201,6 +201,11 @@ func (c *HAProxy) AppContainer(_ context.Context, _ client.Client, spec *api.Pod
 		appc.Lifecycle = &cr.Spec.HAProxy.Lifecycle
 	}
 
+	if cr.CompareVersionWith("1.19.0") >= 0 {
+		extraMounts := api.ExtraPVCVolumeMounts(ctx, spec.ExtraPVCs)
+		appc.VolumeMounts = append(appc.VolumeMounts, extraMounts...)
+	}
+
 	return appc, nil
 }
 
diff --git a/pkg/pxc/app/statefulset/haproxy_test.go b/pkg/pxc/app/statefulset/haproxy_test.go
index 6d52d06005..26ad6258df 100644
--- a/pkg/pxc/app/statefulset/haproxy_test.go
+++ b/pkg/pxc/app/statefulset/haproxy_test.go
@@ -4,12 +4,176 @@ import (
 	"reflect"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
+
 	api "github.com/percona/percona-xtradb-cluster-operator/pkg/apis/pxc/v1"
+	"github.com/percona/percona-xtradb-cluster-operator/pkg/pxc/app"
+	"github.com/percona/percona-xtradb-cluster-operator/pkg/test"
 	"github.com/percona/percona-xtradb-cluster-operator/pkg/version"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
+func TestAppContainer_HAProxy(t *testing.T) {
+	secretName := "my-secret"
+
+	tests := map[string]struct {
+		spec              api.PerconaXtraDBClusterSpec
+		expectedContainer func() corev1.Container
+	}{
+		"latest cr container construction": {
+			spec: api.PerconaXtraDBClusterSpec{
+				CRVersion: version.Version(),
+				HAProxy: &api.HAProxySpec{
+					PodSpec: api.PodSpec{
+						Image:             "test-image",
+						ImagePullPolicy:   corev1.PullIfNotPresent,
+						EnvVarsSecretName: "test-secret",
+						LivenessProbes: corev1.Probe{
+							TimeoutSeconds: 5,
+						},
+						ReadinessProbes: corev1.Probe{
+							TimeoutSeconds: 15,
+						},
+					},
+				},
+				PXC: &api.PXCSpec{
+					PodSpec: &api.PodSpec{},
+				},
+			},
+			expectedContainer: func() corev1.Container {
+				return defaultExpectedHAProxyContainer()
+			},
+		},
+		"container construction with extra pvcs": {
+			spec: api.PerconaXtraDBClusterSpec{
+				CRVersion: version.Version(),
+				HAProxy: &api.HAProxySpec{
+					PodSpec: api.PodSpec{
+						Image:             "test-image",
+						ImagePullPolicy:   corev1.PullIfNotPresent,
+						EnvVarsSecretName: "test-secret",
+						LivenessProbes: corev1.Probe{
+							TimeoutSeconds: 5,
+						},
+						ReadinessProbes: corev1.Probe{
+							TimeoutSeconds: 15,
+						},
+						ExtraPVCs: []api.ExtraPVC{
+							{
+								Name:      "extra-data-volume",
+								ClaimName: "extra-storage-0",
+								MountPath: "/var/lib/haproxy-extra",
+							},
+							{
+								Name:      "backup-volume",
+								ClaimName: "backup-storage-0",
+								MountPath: "/backups",
+								SubPath:   "haproxy",
+							},
+						},
+					},
+				},
+				PXC: &api.PXCSpec{
+					PodSpec: &api.PodSpec{},
+				},
+			},
+			expectedContainer: func() corev1.Container {
+				c := defaultExpectedHAProxyContainer()
+				c.VolumeMounts = append(c.VolumeMounts,
+					corev1.VolumeMount{
+						Name:      "extra-data-volume",
+						MountPath: "/var/lib/haproxy-extra",
+					},
+					corev1.VolumeMount{
+						Name:      "backup-volume",
+						MountPath: "/backups",
+						SubPath:   "haproxy",
+					},
+				)
+				return c
+			},
+		},
+	}
+
+	for name, tt := range tests {
+		t.Run(name, func(t *testing.T) {
+			cr := &api.PerconaXtraDBCluster{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "test-cluster",
+					Namespace: "test-ns",
+					UID:       "test-uid",
+				},
+				Spec: tt.spec,
+			}
+
+			client := test.BuildFakeClient()
+			haproxy := &HAProxy{cr: cr}
+
+			c, err := haproxy.AppContainer(t.Context(), client, &tt.spec.HAProxy.PodSpec, secretName, cr, nil)
+			assert.Equal(t, tt.expectedContainer(), c)
+			assert.NoError(t, err)
+		})
+	}
+}
+
+func defaultExpectedHAProxyContainer() corev1.Container {
+	fvar := true
+	return corev1.Container{
+		Name:            "haproxy",
+		Image:           "test-image",
+		ImagePullPolicy: corev1.PullIfNotPresent,
+		Command:         []string{"/opt/percona/haproxy-entrypoint.sh"},
+		Args:            []string{"haproxy"},
+		Ports: []corev1.ContainerPort{
+			{ContainerPort: 3306, Name: "mysql"},
+			{ContainerPort: 3307, Name: "mysql-replicas"},
+			{ContainerPort: 3309, Name: "proxy-protocol"},
+			{ContainerPort: 33062, Name: "mysql-admin"},
+			{ContainerPort: 33060, Name: "mysqlx"},
+			{ContainerPort: 8404, Name: "stats"},
+		},
+		VolumeMounts: []corev1.VolumeMount{
+			{Name: "haproxy-custom", MountPath: "/etc/haproxy-custom/"},
+			{Name: "haproxy-auto", MountPath: "/etc/haproxy/pxc"},
+			{Name: app.BinVolumeName, MountPath: app.BinVolumeMountPath},
+			{Name: "mysql-users-secret-file", MountPath: "/etc/mysql/mysql-users-secret"},
+			{Name: "test-secret", MountPath: "/etc/mysql/haproxy-env-secret"},
+		},
+		Env: []corev1.EnvVar{
+			{Name: "PXC_SERVICE", Value: "test-cluster-pxc"},
+			{Name: "LIVENESS_CHECK_TIMEOUT", Value: "5"},
+			{Name: "READINESS_CHECK_TIMEOUT", Value: "15"},
+		},
+		EnvFrom: []corev1.EnvFromSource{
+			{
+				SecretRef: &corev1.SecretEnvSource{
+					LocalObjectReference: corev1.LocalObjectReference{
+						Name: "test-secret",
+					},
+					Optional: &fvar,
+				},
+			},
+		},
+		ReadinessProbe: &corev1.Probe{
+			TimeoutSeconds: 15,
+			ProbeHandler: corev1.ProbeHandler{
+				Exec: &corev1.ExecAction{
+					Command: []string{"/opt/percona/haproxy_readiness_check.sh"},
+				},
+			},
+		},
+		LivenessProbe: &corev1.Probe{
+			TimeoutSeconds: 5,
+			ProbeHandler: corev1.ProbeHandler{
+				Exec: &corev1.ExecAction{
+					Command: []string{"/opt/percona/haproxy_liveness_check.sh"},
+				},
+			},
+		},
+	}
+}
+
 func TestSidecarContainers_HAProxy(t *testing.T) {
 	tests := map[string]struct {
 		spec            api.PodSpec
diff --git a/pkg/pxc/app/statefulset/proxysql.go b/pkg/pxc/app/statefulset/proxysql.go
index 366283c1f8..dc3fac9993 100644
--- a/pkg/pxc/app/statefulset/proxysql.go
+++ b/pkg/pxc/app/statefulset/proxysql.go
@@ -57,7 +57,7 @@ func proxyInitContainers(cr *api.PerconaXtraDBCluster, initImageName string) []c
 	return inits
 }
 
-func (c *Proxy) AppContainer(_ context.Context, _ client.Client, spec *api.PodSpec, secrets string, cr *api.PerconaXtraDBCluster,
+func (c *Proxy) AppContainer(ctx context.Context, _ client.Client, spec *api.PodSpec, secrets string, cr *api.PerconaXtraDBCluster,
 	availableVolumes []corev1.Volume,
 ) (corev1.Container, error) {
 	appc := corev1.Container{
@@ -220,6 +220,9 @@ func (c *Proxy) AppContainer(_ context.Context, _ client.Client, spec *api.PodSp
 				Value: "true",
 			})
 		}
+
+		extraMounts := api.ExtraPVCVolumeMounts(ctx, spec.ExtraPVCs)
+		appc.VolumeMounts = append(appc.VolumeMounts, extraMounts...)
 	}
 
 	return appc, nil
diff --git a/pkg/pxc/app/statefulset/proxysql_test.go b/pkg/pxc/app/statefulset/proxysql_test.go
index 4b0a3a2778..4ad7b8b23a 100644
--- a/pkg/pxc/app/statefulset/proxysql_test.go
+++ b/pkg/pxc/app/statefulset/proxysql_test.go
@@ -100,6 +100,49 @@ func TestAppContainer_ProxySQL(t *testing.T) {
 				return c
 			},
 		},
+		"container construction with extra pvcs": {
+			spec: api.PerconaXtraDBClusterSpec{
+				CRVersion: version.Version(),
+				ProxySQL: &api.ProxySQLSpec{
+					PodSpec: api.PodSpec{
+						Image:             "test-image",
+						ImagePullPolicy:   corev1.PullIfNotPresent,
+						EnvVarsSecretName: "test-secret",
+						ExtraPVCs: []api.ExtraPVC{
+							{
+								Name:      "extra-data-volume",
+								ClaimName: "extra-storage-0",
+								MountPath: "/var/lib/proxysql-extra",
+							},
+							{
+								Name:      "backup-volume",
+								ClaimName: "backup-storage-0",
+								MountPath: "/backups",
+								SubPath:   "proxysql",
+							},
+						},
+					},
+				},
+				PXC: &api.PXCSpec{
+					PodSpec: &api.PodSpec{},
+				},
+			},
+			expectedContainer: func() corev1.Container {
+				c := defaultExpectedProxySQLContainer()
+				c.VolumeMounts = append(c.VolumeMounts,
+					corev1.VolumeMount{
+						Name:      "extra-data-volume",
+						MountPath: "/var/lib/proxysql-extra",
+					},
+					corev1.VolumeMount{
+						Name:      "backup-volume",
+						MountPath: "/backups",
+						SubPath:   "proxysql",
+					},
+				)
+				return c
+			},
+		},
 	}
 
 	for name, tt := range tests {

From 991eabeff39f8781dbb7f6bddb8f578d7fc5c644 Mon Sep 17 00:00:00 2001
From: George Kechagias <geo.kechagias@gmail.com>
Date: Thu, 4 Dec 2025 10:35:05 +0100
Subject: [PATCH 10/12] move validations to cr level

---
 ...pxc.percona.com_perconaxtradbclusters.yaml |  9 ++++++
 deploy/bundle.yaml                            |  9 ++++++
 deploy/crd.yaml                               |  9 ++++++
 deploy/cw-bundle.yaml                         |  9 ++++++
 pkg/apis/pxc/v1/pxc_types.go                  | 13 ++------
 pkg/apis/pxc/v1/pxc_types_test.go             | 30 -------------------
 6 files changed, 39 insertions(+), 40 deletions(-)

diff --git a/config/crd/bases/pxc.percona.com_perconaxtradbclusters.yaml b/config/crd/bases/pxc.percona.com_perconaxtradbclusters.yaml
index 819a478f37..568d29de2c 100644
--- a/config/crd/bases/pxc.percona.com_perconaxtradbclusters.yaml
+++ b/config/crd/bases/pxc.percona.com_perconaxtradbclusters.yaml
@@ -1753,10 +1753,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
@@ -5337,10 +5340,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
@@ -8377,10 +8383,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
diff --git a/deploy/bundle.yaml b/deploy/bundle.yaml
index 22febcdb23..1b32aac8cf 100644
--- a/deploy/bundle.yaml
+++ b/deploy/bundle.yaml
@@ -3060,10 +3060,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
@@ -6644,10 +6647,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
@@ -9684,10 +9690,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
diff --git a/deploy/crd.yaml b/deploy/crd.yaml
index c20a69c047..f8dfb4e373 100644
--- a/deploy/crd.yaml
+++ b/deploy/crd.yaml
@@ -3060,10 +3060,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
@@ -6644,10 +6647,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
@@ -9684,10 +9690,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
diff --git a/deploy/cw-bundle.yaml b/deploy/cw-bundle.yaml
index 0c7dfc6095..af159c40f1 100644
--- a/deploy/cw-bundle.yaml
+++ b/deploy/cw-bundle.yaml
@@ -3060,10 +3060,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
@@ -6644,10 +6647,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
@@ -9684,10 +9690,13 @@ spec:
                     items:
                       properties:
                         claimName:
+                          minLength: 1
                           type: string
                         mountPath:
+                          minLength: 1
                           type: string
                         name:
+                          minLength: 1
                           type: string
                         readOnly:
                           type: boolean
diff --git a/pkg/apis/pxc/v1/pxc_types.go b/pkg/apis/pxc/v1/pxc_types.go
index 6af4754a12..da290ab486 100644
--- a/pkg/apis/pxc/v1/pxc_types.go
+++ b/pkg/apis/pxc/v1/pxc_types.go
@@ -941,14 +941,17 @@ type VolumeSpec struct {
 type ExtraPVC struct {
 	// Name of the volume as it will be referenced in the pod
 	// +kubebuilder:validation:Required
+	// +kubebuilder:validation:MinLength=1
 	Name string `json:"name"`
 
 	// ClaimName is the name of the existing PersistentVolumeClaim to mount
 	// +kubebuilder:validation:Required
+	// +kubebuilder:validation:MinLength=1
 	ClaimName string `json:"claimName"`
 
 	// MountPath is the path inside the container where the volume will be mounted
 	// +kubebuilder:validation:Required
+	// +kubebuilder:validation:MinLength=1
 	MountPath string `json:"mountPath"`
 
 	// SubPath within the volume from which the container's volume should be mounted
@@ -1790,16 +1793,6 @@ func validateExtraPVCs(extraPVCs []ExtraPVC) error {
 	mountPaths := make(map[string]struct{}, len(extraPVCs))
 
 	for _, epvc := range extraPVCs {
-		if epvc.Name == "" {
-			return errors.New("extraPVC: name cannot be empty")
-		}
-		if epvc.ClaimName == "" {
-			return errors.Errorf("extraPVC %s: claimName cannot be empty", epvc.Name)
-		}
-		if epvc.MountPath == "" {
-			return errors.Errorf("extraPVC %s: mountPath cannot be empty", epvc.Name)
-		}
-
 		if _, ok := names[epvc.Name]; ok {
 			return errors.Errorf("extraPVC: duplicate volume name %s", epvc.Name)
 		}
diff --git a/pkg/apis/pxc/v1/pxc_types_test.go b/pkg/apis/pxc/v1/pxc_types_test.go
index c68c0671b3..d28293d233 100644
--- a/pkg/apis/pxc/v1/pxc_types_test.go
+++ b/pkg/apis/pxc/v1/pxc_types_test.go
@@ -409,36 +409,6 @@ func TestValidateExtraPVCs(t *testing.T) {
 				},
 			},
 		},
-		"empty name": {
-			extraPVCs: []ExtraPVC{
-				{
-					Name:      "",
-					ClaimName: "extra-storage-0",
-					MountPath: "/var/lib/mysql-extra",
-				},
-			},
-			errMsg: "extraPVC: name cannot be empty",
-		},
-		"empty claim name": {
-			extraPVCs: []ExtraPVC{
-				{
-					Name:      "extra-data",
-					ClaimName: "",
-					MountPath: "/var/lib/mysql-extra",
-				},
-			},
-			errMsg: "extraPVC extra-data: claimName cannot be empty",
-		},
-		"empty mount path": {
-			extraPVCs: []ExtraPVC{
-				{
-					Name:      "extra-data",
-					ClaimName: "extra-storage-0",
-					MountPath: "",
-				},
-			},
-			errMsg: "extraPVC extra-data: mountPath cannot be empty",
-		},
 		"duplicate volume name": {
 			extraPVCs: []ExtraPVC{
 				{

From 62a77289edd023307c0b7055ba70464be688de55 Mon Sep 17 00:00:00 2001
From: George Kechagias <geo.kechagias@gmail.com>
Date: Thu, 4 Dec 2025 11:13:55 +0100
Subject: [PATCH 11/12] cr changes

---
 e2e-tests/extra-pvc/run      | 36 ++++++++++++++++++------------------
 pkg/apis/pxc/v1/pxc_types.go |  7 +++++--
 pkg/pxc/statefulset.go       |  2 +-
 3 files changed, 24 insertions(+), 21 deletions(-)

diff --git a/e2e-tests/extra-pvc/run b/e2e-tests/extra-pvc/run
index 4f5e745e1b..c076647010 100755
--- a/e2e-tests/extra-pvc/run
+++ b/e2e-tests/extra-pvc/run
@@ -8,13 +8,13 @@ test_dir=$(realpath $(dirname $0))
 function create_extra_pvcs() {
 	local ns=$1
 
-	echo "Creating extra PVCs in namespace ${ns}"
+	log "Creating extra PVCs in namespace ${ns}"
 	kubectl_bin apply -f ${test_dir}/conf/extra-pvc.yml -n ${ns}
 
-	echo "Waiting for source PVC to be bound"
+	log "Waiting for source PVC to be bound"
 	kubectl_bin wait --for=jsonpath='{.status.phase}'=Bound pvc/extra-storage-source -n ${ns} --timeout=60s
 
-	echo "Waiting for populator pod to be ready"
+	log "Waiting for populator pod to be ready"
 	kubectl_bin wait --for=condition=Ready pod/pvc-populator -n ${ns} --timeout=60s
 }
 
@@ -22,14 +22,14 @@ function verify_extra_pvc_mounted() {
 	local pod=$1
 	local mount_path=$2
 
-	echo "Verifying extra PVC is mounted in pod ${pod} at ${mount_path}"
+	log "Verifying extra PVC is mounted in pod ${pod} at ${mount_path}"
 
 	if ! kubectl_bin exec ${pod} -c pxc -- test -d ${mount_path}; then
-		echo "Mount path ${mount_path} does not exist in pod ${pod}"
+		log "Mount path ${mount_path} does not exist in pod ${pod}"
 		exit 1
 	fi
 
-	echo "Mount path ${mount_path} exists in pod ${pod}"
+	log "Mount path ${mount_path} exists in pod ${pod}"
 }
 
 function verify_extra_pvc_in_statefulset() {
@@ -37,35 +37,35 @@ function verify_extra_pvc_in_statefulset() {
 	local expected_claim_name=$2
 	local expected_mount_path=$3
 
-	echo "Verifying extra PVC configuration in StatefulSet ${cluster}-pxc"
+	log "Verifying extra PVC configuration in StatefulSet ${cluster}-pxc"
 
 	local volume_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json \
 		| jq --arg claim "${expected_claim_name}" '.spec.template.spec.volumes[] | select(.persistentVolumeClaim.claimName == $claim) | .name' -r)
 
 	if [[ -z $volume_exists ]]; then
-		echo "Volume with claimName ${expected_claim_name} not found in StatefulSet"
+		log "Volume with claimName ${expected_claim_name} not found in StatefulSet"
 		kubectl_bin get statefulset ${cluster}-pxc -o yaml
 		exit 1
 	fi
 
-	echo "Volume ${volume_exists} with claimName ${expected_claim_name} found in StatefulSet"
+	log "Volume ${volume_exists} with claimName ${expected_claim_name} found in StatefulSet"
 
 	local mount_exists=$(kubectl_bin get statefulset ${cluster}-pxc -o json \
 		| jq --arg path "${expected_mount_path}" '.spec.template.spec.containers[] | select(.name == "pxc") | .volumeMounts[] | select(.mountPath == $path) | .name' -r)
 
 	if [[ -z $mount_exists ]]; then
-		echo "Volume mount with mountPath ${expected_mount_path} not found in pxc container"
+		log "Volume mount with mountPath ${expected_mount_path} not found in pxc container"
 		kubectl_bin get statefulset ${cluster}-pxc -o yaml
 		exit 1
 	fi
 
-	echo "Volume mount ${mount_exists} with mountPath ${expected_mount_path} found in pxc container"
+	log "Volume mount ${mount_exists} with mountPath ${expected_mount_path} found in pxc container"
 }
 
 function patch_cluster_add_extra_pvcs() {
 	local cluster=$1
 
-	echo "Patching cluster ${cluster} to add extraPVCs"
+	log "Patching cluster ${cluster} to add extraPVCs"
 
 	kubectl_bin patch pxc ${cluster} --type=json -p='[
 		{
@@ -86,7 +86,7 @@ function patch_cluster_add_extra_pvcs() {
 function patch_cluster_remove_extra_pvcs() {
 	local cluster=$1
 
-	echo "Patching cluster ${cluster} to remove extraPVCs"
+	log "Patching cluster ${cluster} to remove extraPVCs"
 
 	kubectl_bin patch pxc ${cluster} --type=json -p='[
 		{
@@ -99,7 +99,7 @@ function patch_cluster_remove_extra_pvcs() {
 function patch_cluster_add_multiple_extra_pvcs() {
 	local cluster=$1
 
-	echo "Patching cluster ${cluster} to add multiple extraPVCs"
+	log "Patching cluster ${cluster} to add multiple extraPVCs"
 
 	kubectl_bin patch pxc ${cluster} --type=json -p='[
 		{
@@ -159,10 +159,10 @@ desc 'verify multiple extra PVCs are mounted'
 for i in 0 1 2; do
 	verify_extra_pvc_mounted "${cluster}-pxc-${i}" "/var/lib/mysql-extra-1"
 	if kubectl_bin exec ${cluster}-pxc-${i} -c pxc -- touch /var/lib/mysql-extra-2/test-write 2>/dev/null; then
-		echo "Read-only mount /var/lib/mysql-extra-2 is writable in pod ${cluster}-pxc-${i}"
+		log "Read-only mount /var/lib/mysql-extra-2 is writable in pod ${cluster}-pxc-${i}"
 		exit 1
 	fi
-	echo "Read-only mount /var/lib/mysql-extra-2 is properly read-only in pod ${cluster}-pxc-${i}"
+	log "Read-only mount /var/lib/mysql-extra-2 is properly read-only in pod ${cluster}-pxc-${i}"
 done
 
 desc 'test removing extra PVCs from cluster'
@@ -176,11 +176,11 @@ for claim in extra-storage-1 extra-storage-2; do
 		| jq --arg claim "${claim}" '.spec.template.spec.volumes[] | select(.persistentVolumeClaim.claimName == $claim) | .name' -r)
 
 	if [[ -n $volume_exists ]]; then
-		echo "Volume with claimName ${claim} still exists in StatefulSet after removal"
+		log "Volume with claimName ${claim} still exists in StatefulSet after removal"
 		exit 1
 	fi
 done
-echo "Extra PVCs successfully removed from StatefulSet"
+log "Extra PVCs successfully removed from StatefulSet"
 
 cluster2="some-name-2"
 desc "Deleting ${cluster} and recreating PXC cluster ${cluster1}"
diff --git a/pkg/apis/pxc/v1/pxc_types.go b/pkg/apis/pxc/v1/pxc_types.go
index da290ab486..f6c1001fa4 100644
--- a/pkg/apis/pxc/v1/pxc_types.go
+++ b/pkg/apis/pxc/v1/pxc_types.go
@@ -21,6 +21,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/util/intstr"
+	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/log"
 
@@ -1724,7 +1725,9 @@ func AddSidecarPVCs(log logr.Logger, existing, sidecarPVCs []corev1.PersistentVo
 
 // ExtraPVCVolumes generates Kubernetes volumes from ExtraPVC configurations.
 // Each ExtraPVC references an existing PersistentVolumeClaim by name.
-func ExtraPVCVolumes(log logr.Logger, extraPVCs []ExtraPVC) []corev1.Volume {
+func ExtraPVCVolumes(ctx context.Context, extraPVCs []ExtraPVC) []corev1.Volume {
+	logger := ctrl.LoggerFrom(ctx)
+
 	if len(extraPVCs) == 0 {
 		return nil
 	}
@@ -1734,7 +1737,7 @@ func ExtraPVCVolumes(log logr.Logger, extraPVCs []ExtraPVC) []corev1.Volume {
 
 	for _, epvc := range extraPVCs {
 		if _, ok := names[epvc.Name]; ok {
-			log.Info("Duplicate extra PVC volume name, skipping", "volumeName", epvc.Name)
+			logger.Info("Duplicate extra PVC volume name, skipping", "volumeName", epvc.Name)
 			continue
 		}
 		names[epvc.Name] = struct{}{}
diff --git a/pkg/pxc/statefulset.go b/pkg/pxc/statefulset.go
index af33b3251c..2f0905ffdc 100644
--- a/pkg/pxc/statefulset.go
+++ b/pkg/pxc/statefulset.go
@@ -97,7 +97,7 @@ func StatefulSet(
 	pod.Volumes = api.AddSidecarVolumes(log, pod.Volumes, podSpec.SidecarVolumes)
 
 	if cr.CompareVersionWith("1.19.0") >= 0 {
-		extraVolumes := api.ExtraPVCVolumes(log, podSpec.ExtraPVCs)
+		extraVolumes := api.ExtraPVCVolumes(ctx, podSpec.ExtraPVCs)
 		pod.Volumes = append(pod.Volumes, extraVolumes...)
 	}
 

From ee0ffc971bd5f584147eb638a5bbf8ad706998db Mon Sep 17 00:00:00 2001
From: George Kechagias <geo.kechagias@gmail.com>
Date: Thu, 4 Dec 2025 11:42:49 +0100
Subject: [PATCH 12/12] fix logger

---
 pkg/apis/pxc/v1/pxc_types.go | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/pkg/apis/pxc/v1/pxc_types.go b/pkg/apis/pxc/v1/pxc_types.go
index f6c1001fa4..0537b492f7 100644
--- a/pkg/apis/pxc/v1/pxc_types.go
+++ b/pkg/apis/pxc/v1/pxc_types.go
@@ -21,7 +21,6 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/util/intstr"
-	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/log"
 
@@ -1726,7 +1725,7 @@ func AddSidecarPVCs(log logr.Logger, existing, sidecarPVCs []corev1.PersistentVo
 // ExtraPVCVolumes generates Kubernetes volumes from ExtraPVC configurations.
 // Each ExtraPVC references an existing PersistentVolumeClaim by name.
 func ExtraPVCVolumes(ctx context.Context, extraPVCs []ExtraPVC) []corev1.Volume {
-	logger := ctrl.LoggerFrom(ctx)
+	logger := log.FromContext(ctx)
 
 	if len(extraPVCs) == 0 {
 		return nil