kubernetes运营商是自动化Kubernetes上复杂应用程序的强大方法。在这篇博客文章中，我们将为想要学习如何创建和使用运营商的Kubernetes开发人员提供动手指南。我们将介绍运营商的基础知识，包括如何定义自定义资源，创建控制器和管理对帐循环。我们还将为MySQL提供操作符。
先决条件
GO版本v1.20.0+
Docker版本17.03+。
kubectl版本v1.11.3+。
访问Kubernetes v1.11.3+ cluster。
安装kubebuilder
$ curl -L -o kubebuilder "https://go.kubebuilder.io/dl/latest/$(go env GOOS)/$(go env GOARCH)"
$ chmod +x kubebuilder
$ mv kubebuilder /usr/local/bin/
$ kubebuilder version
Version: main.version{KubeBuilderVersion:"3.11.1", KubernetesVendor:"1.27.1", GitCommit:"1dc8ed95f7cc55fef3151f749d3d541bec3423c9", BuildDate:"2023-07-03T13:10:56Z", GoOs:"linux", GoArch:"amd64"}
init/bootstrap项目
$ mkdir -p ~/ops/mysql-operator && cd /mysql-operator
$ kubebuilder init --domain dpuigerarde.com --repo github.com/dpuig/mysql-operator
kubebuilder init --domain命令用于初始化新的kubernetes操作员项目。域名标志为项目的自定义资源指定了Kubernetes组。域标志的默认值是my.domain。
创建一个API
$ kubebuilder create api --group apps --version v1alpha1 --kind MySQLCluster
kubebuilder create api --group命令用于在Kubernetes操作员项目中创建新的API（自定义资源定义）。组标志为API指定Kubernetes组。组标志的默认值是项目的域名。
如果您按y进行创建资源[Y/N]和创建控制器[Y/N]，那么这将创建文件
api
└── v1alpha1
├── groupversion_info.go
├── mysqlcluster_types.go
└── zz_generated.deepcopy.go
定义API的地方
也文件
internal
└── controller
├── mysqlcluster_controller.go
└── suite_test.go
在此类对帐业务逻辑的情况下（CRD）。
自定义资源定义（CRD）
mySqlClustersPec CRD定义了MySQLCluster资源的架构。它应该包括以下字段：
deploymentName： mysql db的名称。
复制品： mysql豆荚的数量。
版本：使用MySQL的版本。
密码：默认管理密码。
在生成的项目中，查找api/v1alpha1/mysqlcluster_types.go
编辑MySQLClusterSpec和MySQLClusterStatus结构：
type MySQLClusterSpec struct {
// INSERT ADDITIONAL SPEC FIELDS - desired state of cluster
// Important: Run "make" to regenerate code after modifying this file
// Foo is an example field of MySQLCluster. Edit mysqlcluster_types.go to remove/update
// Foo string `json:"foo,omitempty"`
// +kubebuilder:validation:Required
// +kubebuilder:validation:Format:=string
// the name of the deployment
DeploymentName string `json:"deploymentName"`
// +kubebuilder:validation:Required
// +kubebuilder:validation:Minimum=0
// the number of replicas
Replicas *int32 `json:"replicas"`
Version string `json:"version"`
// +kubebuilder:validation:Required
// +kubebuilder:validation:Format:=string
Password string `json:"password"`
}
type MySQLClusterStatus struct {
// INSERT ADDITIONAL STATUS FIELD - define observed state of cluster
// Important: Run "make" to regenerate code after modifying this file
// this is equal deployment.status.availableReplicas
// +optional
AvailableReplicas int32 `json:"availableReplicas"`
}
然后运行：
$ make manifests
实现控制器逻辑
编辑位于internal/controller/mysqlcluster_controller.go
很快，我们将专注于博客文章，以关注API类型的详细信息，尤其是控制器中的逻辑。对于这种情况，总的来说，该控制器负责部署将启动MySQL DB的部署。
package controller
import (
"context"
"k8s.io/apimachinery/pkg/runtime"
"k8s.io/client-go/tools/record"
ctrl "sigs.k8s.io/controller-runtime"
"sigs.k8s.io/controller-runtime/pkg/client"
"sigs.k8s.io/controller-runtime/pkg/log"
"github.com/go-logr/logr"
appsv1 "k8s.io/api/apps/v1"
corev1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
samplecontrollerv1alpha1 "github.com/dpuig/mysql-operator/api/v1alpha1"
)
var (
deploymentOwnerKey = ".metadata.controller"
apiGVStr = samplecontrollerv1alpha1.GroupVersion.String()
)
// MySQLClusterReconciler reconciles a MySQLCluster object
type MySQLClusterReconciler struct {
client.Client
Log logr.Logger
Scheme *runtime.Scheme
Recorder record.EventRecorder
}
//+kubebuilder:rbac:groups=apps.dpuigerarde.com,resources=mysqlclusters,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=apps.dpuigerarde.com,resources=mysqlclusters/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=apps.dpuigerarde.com,resources=mysqlclusters/finalizers,verbs=update
// Reconcile is part of the main kubernetes reconciliation loop which aims to
// move the current state of the cluster closer to the desired state.
// TODO(user): Modify the Reconcile function to compare the state specified by
// the MySQLCluster object against the actual cluster state, and then
// perform operations to make the cluster state reflect the state specified by
// the user.
//
// For more details, check Reconcile and its Result here:
// - https://pkg.go.dev/sigs.k8s.io/controller-runtime@v0.15.0/pkg/reconcile
func (r *MySQLClusterReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
_ = log.FromContext(ctx)
log := r.Log.WithValues("mysqlCluster", req.NamespacedName)
var mysqlCluster samplecontrollerv1alpha1.MySQLCluster
log.Info("fetching MySQLCluster Resource")
if err := r.Get(ctx, req.NamespacedName, &mysqlCluster); err != nil {
log.Error(err, "unable to fetch MySQLCluster")
return ctrl.Result{}, client.IgnoreNotFound(err)
}
if err := r.cleanupOwnedResources(ctx, log, &mysqlCluster); err != nil {
log.Error(err, "failed to clean up old Deployment resources for this Foo")
return ctrl.Result{}, err
}
// get deploymentName from mysqlCluster.Spec
deploymentName := mysqlCluster.Spec.DeploymentName
// define deployment template using deploymentName
deploy := &appsv1.Deployment{
ObjectMeta: metav1.ObjectMeta{
Name: deploymentName,
Namespace: req.Namespace,
},
}
// Create or Update deployment object
if _, err := ctrl.CreateOrUpdate(ctx, r.Client, deploy, func() error {
replicas := int32(1)
if mysqlCluster.Spec.Replicas != nil {
replicas = *mysqlCluster.Spec.Replicas
}
deploy.Spec.Replicas = &replicas
labels := map[string]string{
"app": "mysql",
"controller": req.Name,
}
// set labels to spec.selector for our deployment
if deploy.Spec.Selector == nil {
deploy.Spec.Selector = &metav1.LabelSelector{MatchLabels: labels}
}
// set labels to template.objectMeta for our deployment
if deploy.Spec.Template.ObjectMeta.Labels == nil {
deploy.Spec.Template.ObjectMeta.Labels = labels
}
// set a container for our deployment
containers := []corev1.Container{
{
Name: "db",
Image: "mysql:" + mysqlCluster.Spec.Version,
Env: []corev1.EnvVar{
{
Name: "MYSQL_ROOT_PASSWORD",
Value: mysqlCluster.Spec.Password,
},
},
Command: []string{"mysqld", "--user=root"},
Args: []string{"--default-authentication-plugin=mysql_native_password"},
Ports: []corev1.ContainerPort{
{
Name: "mysql",
ContainerPort: 3306,
},
},
VolumeMounts: []corev1.VolumeMount{
{
Name: "mysql-persistent-storage",
MountPath: "/var/lib/mysql",
},
},
SecurityContext: &corev1.SecurityContext{
RunAsUser: func() *int64 { i := int64(1001); return &i }(),
RunAsGroup: func() *int64 { i := int64(1001); return &i }(),
},
},
}
// set containers to template.spec.containers for our deployment
if deploy.Spec.Template.Spec.Containers == nil {
deploy.Spec.Template.Spec.Containers = containers
}
deploy.Spec.Strategy.Type = "Recreate"
deploy.Spec.Template.Spec.Volumes = []corev1.Volume{
{
Name: "mysql-persistent-storage",
VolumeSource: corev1.VolumeSource{
PersistentVolumeClaim: &corev1.PersistentVolumeClaimVolumeSource{
ClaimName: "mysql-pv-claim",
},
},
},
}
deploy.Spec.Template.Spec.SecurityContext = &corev1.PodSecurityContext{
FSGroup: func() *int64 { i := int64(1001); return &i }(),
}
// set the owner so that garbage collection can kicks in
if err := ctrl.SetControllerReference(&mysqlCluster, deploy, r.Scheme); err != nil {
log.Error(err, "unable to set ownerReference from mysqlCluster to Deployment")
return err
}
return nil
}); err != nil {
// error handling of ctrl.CreateOrUpdate
log.Error(err, "unable to ensure deployment is correct")
return ctrl.Result{}, err
}
// get deployment object from in-memory-cache
var deployment appsv1.Deployment
var deploymentNamespacedName = client.ObjectKey{Namespace: req.Namespace, Name: mysqlCluster.Spec.DeploymentName}
if err := r.Get(ctx, deploymentNamespacedName, &deployment); err != nil {
log.Error(err, "unable to fetch Deployment")
return ctrl.Result{}, client.IgnoreNotFound(err)
}
// set mysqlCluster.status.AvailableReplicas from deployment
availableReplicas := deployment.Status.AvailableReplicas
if availableReplicas == mysqlCluster.Status.AvailableReplicas {
return ctrl.Result{}, nil
}
mysqlCluster.Status.AvailableReplicas = availableReplicas
// update mysqlCluster.status
if err := r.Status().Update(ctx, &mysqlCluster); err != nil {
log.Error(err, "unable to update mysqlCluster status")
return ctrl.Result{}, err
}
// create event for updated mysqlCluster.status
r.Recorder.Eventf(&mysqlCluster, corev1.EventTypeNormal, "Updated", "Update mysqlCluster.status.AvailableReplicas: %d", mysqlCluster.Status.AvailableReplicas)
return ctrl.Result{}, nil
}
// SetupWithManager sets up the controller with the Manager.
func (r *MySQLClusterReconciler) SetupWithManager(mgr ctrl.Manager) error {
ctx := context.Background()
// add deploymentOwnerKey index to deployment object which MySQLCluster resource owns
if err := mgr.GetFieldIndexer().IndexField(ctx, &appsv1.Deployment{}, deploymentOwnerKey, func(rawObj client.Object) []string {
// grab the deployment object, extract the owner...
deployment := rawObj.(*appsv1.Deployment)
owner := metav1.GetControllerOf(deployment)
if owner == nil {
return nil
}
// ...make sure it's a MySQLCluster...
if owner.APIVersion != apiGVStr || owner.Kind != "MySQLCluster" {
return nil
}
// ...and if so, return it
return []string{owner.Name}
}); err != nil {
return err
}
// define to watch targets...Foo resource and owned Deployment
return ctrl.NewControllerManagedBy(mgr).
For(&samplecontrollerv1alpha1.MySQLCluster{}).
Owns(&appsv1.Deployment{}).
Complete(r)
}
// cleanupOwnedResources will delete any existing Deployment resources that
// were created for the given mysqlCluster that no longer match the
// mysqlCluster.spec.deploymentName field.
func (r *MySQLClusterReconciler) cleanupOwnedResources(ctx context.Context, log logr.Logger, mysqlCluster *samplecontrollerv1alpha1.MySQLCluster) error {
log.Info("finding existing Deployments for Foo resource")
// List all deployment resources owned by this mysqlCluster
var deployments appsv1.DeploymentList
if err := r.List(ctx, &deployments, client.InNamespace(mysqlCluster.Namespace), client.MatchingFields(map[string]string{deploymentOwnerKey: mysqlCluster.Name})); err != nil {
return err
}
// Delete deployment if the deployment name doesn't match foo.spec.deploymentName
for _, deployment := range deployments.Items {
if deployment.Name == mysqlCluster.Spec.DeploymentName {
// If this deployment's name matches the one on the Foo resource
// then do not delete it.
continue
}
// Delete old deployment object which doesn't match foo.spec.deploymentName
if err := r.Delete(ctx, &deployment); err != nil {
log.Error(err, "failed to delete Deployment resource")
return err
}
log.Info("delete deployment resource: " + deployment.Name)
r.Recorder.Eventf(mysqlCluster, corev1.EventTypeNormal, "Deleted", "Deleted deployment %q", deployment.Name)
}
return nil
}
项目结构
.
├── api
│ └── v1alpha1
│ ├── groupversion_info.go
│ ├── mysqlcluster_types.go
│ └── zz_generated.deepcopy.go
├── bin
│ ├── controller-gen
│ └── kustomize
├── cmd
│ └── main.go
├── config
│ ├── crd
│ │ ├── bases
│ │ │ └── apps.dpuigerarde.com_mysqlclusters.yaml
│ │ ├── kustomization.yaml
│ │ ├── kustomizeconfig.yaml
│ │ └── patches
│ │ ├── cainjection_in_mysqlclusters.yaml
│ │ └── webhook_in_mysqlclusters.yaml
│ ├── default
│ │ ├── kustomization.yaml
│ │ ├── manager_auth_proxy_patch.yaml
│ │ └── manager_config_patch.yaml
│ ├── manager
│ │ ├── kustomization.yaml
│ │ └── manager.yaml
│ ├── prometheus
│ │ ├── kustomization.yaml
│ │ └── monitor.yaml
│ ├── rbac
│ │ ├── auth_proxy_client_clusterrole.yaml
│ │ ├── auth_proxy_role_binding.yaml
│ │ ├── auth_proxy_role.yaml
│ │ ├── auth_proxy_service.yaml
│ │ ├── kustomization.yaml
│ │ ├── leader_election_role_binding.yaml
│ │ ├── leader_election_role.yaml
│ │ ├── mysqlcluster_editor_role.yaml
│ │ ├── mysqlcluster_viewer_role.yaml
│ │ ├── role_binding.yaml
│ │ ├── role.yaml
│ │ └── service_account.yaml
│ └── samples
│ ├── apps_v1alpha1_mysqlcluster.yaml
│ └── kustomization.yaml
├── Dockerfile
├── go.mod
├── go.sum
├── hack
│ └── boilerplate.go.txt
├── internal
│ └── controller
│ ├── mysqlcluster_controller.go
│ └── suite_test.go
├── Makefile
├── mysql-pv.yaml
├── PROJECT
└── README.md
在本地运行运营商（用于开发）
出于开发目的，您可能希望在本地运行远程群集。这使您可以在开发过程中更快地迭代。
- 设置kubeconfig上下文：
$ export KUBECONFIG=<path-to-your-kubeconfig-file>
- 将CRD安装到集群中：
$ make install
$ kubectl get crds
NAME CREATED AT
mysqlclusters.apps.dpuigerarde.com 2023-08-28T02:22:43Z
出于此示例的目的。我们将创建一些额外的资源，PersistEntVolume和PersistentVolumeclaim，这些资源将作为补充，文件mysql-pv.yaml
apiVersion: v1
kind: PersistentVolume
metadata:
name: mysql-pv-volume
labels:
type: local
spec:
storageClassName: manual
capacity:
storage: 20Gi
accessModes:
- ReadWriteOnce
hostPath:
path: "/mnt/data"
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: mysql-pv-claim
spec:
storageClassName: manual
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 20Gi
应用
$ kubectl apply -f mysql-pv.yaml
$ kubectl get pv,pvc
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
persistentvolume/mysql-pv-volume 20Gi RWO Retain Bound default/mysql-pv-claim manual 103m
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
persistentvolumeclaim/mysql-pv-claim Bound mysql-pv-volume 20Gi RWO manual 103m
- 运行您的控制器（这将在前景中运行，因此，如果要让它运行，请切换到新终端）：
$ make run
部署自定义资源
确保更新config/samples/apps_v1alpha1_mysqlcluster.yaml，并使用您要用于MySQLCluster资源的实际规范。
apiVersion: apps.dpuigerarde.com/v1alpha1
kind: MySQLCluster
metadata:
labels:
app.kubernetes.io/name: mysqlcluster
app.kubernetes.io/instance: mysqlcluster-sample
app.kubernetes.io/part-of: mysql-operator
app.kubernetes.io/managed-by: kustomize
app.kubernetes.io/created-by: mysql-operator
name: mysqlcluster-sample
spec:
# TODO(user): Add fields here
deploymentName: mysqlcluster-sample-deploy
replicas: 1
version: "5.6"
password: example
$ kubectl apply -f apply -f config/samples/apps_v1alpha1_mysqlcluster.yaml
mysqlcluster.apps.dpuigerarde.com/mysqlcluster-sample created
$ kubectl get mysqlclusters
NAME AGE
mysqlcluster-sample 10m
此时，您的操作员应检测自定义资源并执行和解循环，创建指定的MySQL DB。
但是，这是一个包含问题的博客文章，示例存在问题，我希望我可以指望您的帮助来解决此问题。我保证很快就会通过解决问题的解决方案
$ kubectl get deploy
NAME READY UP-TO-DATE AVAILABLE AGE
mysqlcluster-sample-deploy 0/1 1 0 11m
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
mysqlcluster-sample-deploy-79c78b6c5-62jh5 0/1 CrashLoopBackOff 7 (42s ago) 11m
$ kubectl logs mysqlcluster-sample-deploy-79c78b6c5-62jh5
2023-08-28 16:26:24 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2023-08-28 16:26:24 0 [Warning] Can't create test file /var/lib/mysql/mysqlcluster-sample-deploy-79c78b6c5-62jh5.lower-test
2023-08-28 16:26:24 0 [Note] mysqld (mysqld 5.6.51) starting as process 1 ...
2023-08-28 16:26:24 1 [Warning] Can't create test file /var/lib/mysql/mysqlcluster-sample-deploy-79c78b6c5-62jh5.lower-test
2023-08-28 16:26:24 1 [Warning] Can't create test file /var/lib/mysql/mysqlcluster-sample-deploy-79c78b6c5-62jh5.lower-test
2023-08-28 16:26:24 1 [Warning] One can only use the --user switch if running as root
2023-08-28 16:26:24 1 [Note] Plugin 'FEDERATED' is disabled.
mysqld: Table 'mysql.plugin' doesn't exist
2023-08-28 16:26:24 1 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
2023-08-28 16:26:24 1 [Note] InnoDB: Using atomics to ref count buffer pool pages
2023-08-28 16:26:24 1 [Note] InnoDB: The InnoDB memory heap is disabled
2023-08-28 16:26:24 1 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2023-08-28 16:26:24 1 [Note] InnoDB: Memory barrier is not used
2023-08-28 16:26:24 1 [Note] InnoDB: Compressed tables use zlib 1.2.11
2023-08-28 16:26:24 1 [Note] InnoDB: Using Linux native AIO
2023-08-28 16:26:24 1 [Note] InnoDB: Not using CPU crc32 instructions
2023-08-28 16:26:24 1 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2023-08-28 16:26:24 1 [Note] InnoDB: Completed initialization of buffer pool
2023-08-28 16:26:24 1 [ERROR] InnoDB: ./ibdata1 can't be opened in read-write mode
2023-08-28 16:26:24 1 [ERROR] InnoDB: The system tablespace must be writable!
2023-08-28 16:26:24 1 [ERROR] Plugin 'InnoDB' init function returned error.
2023-08-28 16:26:24 1 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
2023-08-28 16:26:24 1 [ERROR] Unknown/unsupported storage engine: InnoDB
2023-08-28 16:26:24 1 [ERROR] Aborting
2023-08-28 16:26:24 1 [Note] Binlog end
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'partition'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'PERFORMANCE_SCHEMA'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_SYS_DATAFILES'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_SYS_TABLESPACES'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_SYS_FOREIGN_COLS'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_SYS_FOREIGN'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_SYS_FIELDS'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_SYS_COLUMNS'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_SYS_INDEXES'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_SYS_TABLESTATS'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_SYS_TABLES'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_FT_INDEX_TABLE'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_FT_INDEX_CACHE'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_FT_CONFIG'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_FT_BEING_DELETED'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_FT_DELETED'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_FT_DEFAULT_STOPWORD'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_METRICS'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_BUFFER_POOL_STATS'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_BUFFER_PAGE_LRU'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_BUFFER_PAGE'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_CMP_PER_INDEX_RESET'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_CMP_PER_INDEX'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_CMPMEM_RESET'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_CMPMEM'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_CMP_RESET'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_CMP'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_LOCK_WAITS'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_LOCKS'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'INNODB_TRX'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'BLACKHOLE'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'ARCHIVE'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'MRG_MYISAM'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'MyISAM'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'MEMORY'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'CSV'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'sha256_password'
2023-08-28 16:26:24 1 [Note] Shutting down plugin 'mysql_old_password'