如何將我的應用程序連接到 kubernetes mysql statefulset

Question

我已經按照鏈接https://kubernetes.io/docs/tasks/run-application/run-replicated-stateful-application/部署了 mysql statefulset，所有 3 個 Z81C3B080DAD537DE7EZE10E09 都運行良好。 我在 Golang 中編寫了一個應用程序，當連接到本地機器上的 MySQL 服務器時，它從 config.toml 文件中讀取 MySQL 環境變量。 config.toml 文件包含這些變量。 當我的應用程序在我的本地機器上運行時使用這些。

MySQLServer = "127.0.0.1"
Port = "3306"
MySQLDatabase = "hss_lte_db"
User = "hss"
Password = "hss" 

現在我想在我的 Kubernetes 集群中部署我的應用程序，以便它連接到 MySQL Statefulset 服務。 我創建了如下所示的部署，但 pod 顯示 Error 和 CrashLoopBackOff。 在如何將我的應用程序連接到 MySQL Statefulset 服務方面需要幫助。 也不確定 MySQLServer 連接字符串在 configMap 中是否正確。

apiVersion: v1 
data:
  config.toml: |
   MySQLServer = "mysql-0.mysql,mysql-1.mysql,mysql-2.mysql"
   Port = "3306"
   MySQLDatabase = "hss_lte_db"
   User = "root"
   Password = ""

   GMLCAddressPort = ":8000"
   NRFIPAddr = "192.168.31.115"
   NRFPort = "30005"

kind: ConfigMap
metadata:
  name: vol-config-gmlcapi
  namespace: default


---
apiVersion: apps/v1 
kind: Deployment
metadata:
  name: gmlc-instance
  namespace: default
spec:
  selector:
    matchLabels:
      app: gmlc-instance
  replicas: 1 
  template:
    metadata:
      labels:
        app: gmlc-instance
        version: "1.0"
    spec:
      nodeName: k8s-worker-node2
      containers:
      - name: gmlc-instance
        image: abrahaa1/gmlcapi:1.0.0
        imagePullPolicy: "Always"
        ports:
        - containerPort: 8000
        volumeMounts:
        - name: configs
          mountPath: /gmlcapp/config.toml
          subPath: config.toml
        volumeMounts:
        - name: gmlc-configs
          mountPath: /gmlcapp/profile.json
          subPath: profile.json
      volumes:
      - name: configs 
        configMap:
          name: vol-config-gmlcapi
      - name: gmlc-configs
        configMap:
          name: vol-config-profile

我對deployment做了一些變量名的修改，所以更新的deployment如上，但還是沒有連接上。 吊艙的描述如下

ubuntu@k8s-master:~/gmlc$ kubectl describe pod gmlc-instance-5898989874-s5s5j -n default
Name:         gmlc-instance-5898989874-s5s5j
Namespace:    default
Priority:     0
Node:         k8s-worker-node2/192.168.31.151
Start Time:   Sun, 10 May 2020 19:50:09 +0300
Labels:       app=gmlc-instance
              pod-template-hash=5898989874
              version=1.0
Annotations:  <none>
Status:       Running
IP:           10.244.1.120
IPs:
  IP:           10.244.1.120
Controlled By:  ReplicaSet/gmlc-instance-5898989874
Containers:
  gmlc-instance:
    Container ID:   docker://b756e67a39b7397e24fe394a8b17bc6de14893329903d3eace4ffde86c335213
    Image:          abrahaa1/gmlcapi:1.0.0
    Image ID:       docker-pullable://abrahaa1/gmlcapi@sha256:e0c8ac2a3db3cde5015ea4030c2099126b79bb2472a9ade42576f7ed1975b73c
    Port:           8000/TCP
    Host Port:      0/TCP
    State:          Terminated
      Reason:       Error
      Exit Code:    1
      Started:      Sun, 10 May 2020 19:50:33 +0300
      Finished:     Sun, 10 May 2020 19:50:33 +0300
    Last State:     Terminated
      Reason:       Error
      Exit Code:    1
      Started:      Sun, 10 May 2020 19:50:17 +0300
      Finished:     Sun, 10 May 2020 19:50:17 +0300
    Ready:          False
    Restart Count:  2
    Environment:    <none>
    Mounts:
      /gmlcapp/profile.json from gmlc-configs (rw,path="profile.json")
      /var/run/secrets/kubernetes.io/serviceaccount from default-token-prqdp (ro)
Conditions:
  Type              Status
  Initialized       True 
  Ready             False 
  ContainersReady   False 
  PodScheduled      True 
Volumes:
  configs:
    Type:      ConfigMap (a volume populated by a ConfigMap)
    Name:      vol-config-gmlcapi
    Optional:  false
  gmlc-configs:
    Type:      ConfigMap (a volume populated by a ConfigMap)
    Name:      vol-config-profile
    Optional:  false
  default-token-prqdp:
    Type:        Secret (a volume populated by a Secret)
    SecretName:  default-token-prqdp
    Optional:    false
QoS Class:       BestEffort
Node-Selectors:  <none>
Tolerations:     node.kubernetes.io/not-ready:NoExecute for 300s
                 node.kubernetes.io/unreachable:NoExecute for 300s
Events:
  Type     Reason   Age               From                       Message
  ----     ------   ----              ----                       -------
  Normal   Pulling  9s (x3 over 28s)  kubelet, k8s-worker-node2  Pulling image "abrahaa1/gmlcapi:1.0.0"
  Normal   Pulled   7s (x3 over 27s)  kubelet, k8s-worker-node2  Successfully pulled image "abrahaa1/gmlcapi:1.0.0"
  Normal   Created  7s (x3 over 26s)  kubelet, k8s-worker-node2  Created container gmlc-instance
  Normal   Started  6s (x3 over 26s)  kubelet, k8s-worker-node2  Started container gmlc-instance
  Warning  BackOff  6s (x3 over 21s)  kubelet, k8s-worker-node2  Back-off restarting failed container

仍然無法連接。

日志 output: ubuntu@k8s-master:~/gmlc$ kubectl 日志 gmlc-instance-5898989874-s5s5j -n 默認 2020/05/10 18:13:21 打開 config.toml: 沒有這樣的文件或目錄

看起來 config.toml 文件是問題所在，我的應用程序需要該文件才能運行。

我有 2 個文件（config.toml 和 profile.json）必須在 /gmlcapp/ 目錄中才能運行應用程序。 因為 profile.json 像上面那樣添加到部署中是巨大的，所以我已經單獨創建了它的 configmap。 這是它的 configmap output

ubuntu@k8s-master:~/gmlc$ kubectl get configmaps
NAME                 DATA   AGE
mysql                2      4d3h
vol-config-gmlcapi   1      97m
vol-config-profile   1      7h56m

這也是我在部署中評論 vol-config-profile 時的日志。

ubuntu@k8s-master:~/gmlc$ kubectl logs gmlc-instance-b4ddd459f-fd8nr -n default
root:@tcp(mysql-0.mysql,mysql-1.mysql,mysql-2.mysql:3306)/hss_lte_db
2020/05/10 18:39:43 GMLC cannot ping MySQL sever
2020/05/10 18:39:43 Cannot read json file
panic: Cannot read json file

goroutine 1 [running]:
log.Panic(0xc00003dda8, 0x1, 0x1)
    /usr/local/go/src/log/log.go:351 +0xac
gmlc-kube/handler.init.0()
    /app/handler/init.go:43 +0x5e9

Answer 1

我通過更改部署中的 volumeMount 使其運行。

解決方案如下：

apiVersion: apps/v1 
kind: Deployment
metadata:
  name: gmlc-instance
  namespace: default
spec:
  selector:
    matchLabels:
      app: gmlc-instance
  replicas: 1 
  template:
    metadata:
      labels:
        app: gmlc-instance
        version: "1.0"
    spec:
      nodeName: k8s-worker-node2
      containers:
      - name: gmlc-instance
        image: abrahaa1/gmlcapi:1.0.0
        imagePullPolicy: "Always"
        ports:
        - containerPort: 8000
        volumeMounts:
        - name: configs
          mountPath: /gmlcapp/config.toml
          subPath: config.toml
          readOnly: true
        - name: gmlc-configs
          mountPath: /gmlcapp/profile.json
          subPath: profile.json
      volumes:
      - name: configs 
        configMap:
          name: vol-config-gmlcapi
      - name: gmlc-configs
        configMap:
          name: vol-config-profile