minikube安装本地目录上的KubeDB [英] KubeDB on minikube mount local directory

问题描述

我试图在minikube上使用 kubedb 来运行postgres，我从本地目录(位于在我的Mac上)，当pod运行时，我没有得到预期的行为，发生了两件事: 一种明显是没有安装，第二种是看到错误pod has unbound immediate PersistentVolumeClaims

I'm trying to run postgres using kubedb on minikube where I mount my data from a local directory (located on my Mac), when the pod runs the I don't get the expected behaviour, two things happen: One is obviously the mount isn't there, and second I see the error pod has unbound immediate PersistentVolumeClaims

首先，这是我的yaml文件:

First, here are my yaml file:

apiVersion: v1
kind: PersistentVolume
metadata:
  name: adminvol
  namespace: demo
  labels:
    release: development
spec:
  capacity:
    storage: 2Gi
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  hostPath:
    path: /Users/myusername/local_docker_poc/admin/lib/postgresql/data

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  namespace: demo
  name: adminpvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi
  selector:
    matchLabels:
      release: development

apiVersion: kubedb.com/v1alpha1
kind: Postgres
metadata:
  name: quick-postgres
  namespace: demo
spec:
  version: "10.2-v2"
  storageType: Durable
  storage:
    accessModes:
    - ReadWriteMany
    resources:
      requests:
        storage: 1Gi
  volumeMounts:
    - mountPath: /busy
      name: naim
      persistentVolumeClaim:
        claimName: adminpvc
  terminationPolicy: WipeOut

根据这(反映在下面的答案中)，我删除了storageClass从我所有的Yaml文件中.

According to this which is reflected in the answer below, I've removed the storageClass from all my yaml files.

describe pod如下:

The describe pod looks like this:

Name:               quick-postgres-0
Namespace:          demo
Priority:           0
PriorityClassName:  <none>
Node:               minikube/10.0.2.15
Start Time:         Wed, 25 Sep 2019 22:18:44 +0300
Labels:             controller-revision-hash=quick-postgres-5d5bcc4698
                    kubedb.com/kind=Postgres
                    kubedb.com/name=quick-postgres
                    kubedb.com/role=primary
                    statefulset.kubernetes.io/pod-name=quick-postgres-0
Annotations:        <none>
Status:             Running
IP:                 172.17.0.7
Controlled By:      StatefulSet/quick-postgres
Containers:
  postgres:
    Container ID:  docker://6bd0946f8197ddf1faf7b52ad0da36810cceff4abb53447679649f1d0dba3c5c
    Image:         kubedb/postgres:10.2-v3
    Image ID:      docker-pullable://kubedb/postgres@sha256:9656942b2322a88d4117f5bfda26ee34d795cd631285d307b55f101c2f2cb8c8
    Port:          5432/TCP
    Host Port:     0/TCP
    Args:
      leader_election
      --enable-analytics=true
      --logtostderr=true
      --alsologtostderr=false
      --v=3
      --stderrthreshold=0
    State:          Running
      Started:      Wed, 25 Sep 2019 22:18:45 +0300
    Ready:          True
    Restart Count:  0
    Environment:
      APPSCODE_ANALYTICS_CLIENT_ID:  90b12fedfef2068a5f608219d5e7904a
      NAMESPACE:                     demo (v1:metadata.namespace)
      PRIMARY_HOST:                  quick-postgres
      POSTGRES_USER:                 <set to the key 'POSTGRES_USER' in secret 'quick-postgres-auth'>      Optional: false
      POSTGRES_PASSWORD:             <set to the key 'POSTGRES_PASSWORD' in secret 'quick-postgres-auth'>  Optional: false
      STANDBY:                       warm
      STREAMING:                     asynchronous
      LEASE_DURATION:                15
      RENEW_DEADLINE:                10
      RETRY_PERIOD:                  2
    Mounts:
      /dev/shm from shared-memory (rw)
      /var/pv from data (rw)
      /var/run/secrets/kubernetes.io/serviceaccount from quick-postgres-token-48rkd (ro)
Conditions:
  Type              Status
  Initialized       True
  Ready             True
  ContainersReady   True
  PodScheduled      True
Volumes:
  data:
    Type:       PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)
    ClaimName:  data-quick-postgres-0
    ReadOnly:   false
  shared-memory:
    Type:       EmptyDir (a temporary directory that shares a pod's lifetime)
    Medium:     Memory
    SizeLimit:  <unset>
  quick-postgres-token-48rkd:
    Type:        Secret (a volume populated by a Secret)
    SecretName:  quick-postgres-token-48rkd
    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
  ----     ------            ----  ----               -------
  Warning  FailedScheduling  39s   default-scheduler  pod has unbound immediate PersistentVolumeClaims
  Normal   Scheduled         39s   default-scheduler  Successfully assigned demo/quick-postgres-0 to minikube
  Normal   Pulled            38s   kubelet, minikube  Container image "kubedb/postgres:10.2-v3" already present on machine
  Normal   Created           38s   kubelet, minikube  Created container
  Normal   Started           38s   kubelet, minikube  Started container

我遵循了有关如何安装pvc的官方手册

I followed the official manual on how to mount a pvc here For debug, I used the same pv and pvc to mount a simple busybox container and it worked fine, that is I can see the mount with data in it:

apiVersion: v1
kind: Pod
metadata:
  name: busybox
  namespace: demo
spec:
  containers:
    - name: busybox
      image: busybox
      command:
        - sleep
        - "3600"
      volumeMounts:
        - mountPath: /busy
          name: adminpvc
  volumes:
    - name: adminpvc
      persistentVolumeClaim:
        claimName: adminpvc

我自己的Pod和KubeDB的唯一区别(据我所知，它背后有一个状态集)是我将storageClass保留在PV和PVC中！如果删除存储类，我会看到容器内的挂载点，但是它是空的并且没有数据

The only difference with my own pod and that of the KubeDB (which to my understanding there's a statefulset behind it) is that I kept the storageClass in the PV and PVC ! if I remove the storage class, I will see the mount point inside the container but it's empty and has no data

推荐答案

您正在使用自定义

You are using the custom Postgres-resource of kubedb.com/v1alpha1.

他们定义了一种自定义方式来处理存储.好像您必须设置spec.storage.storageClassName键，因为

They define a custom way to handle storage. It seems like you must set the spec.storage.storageClassName-key since a

没有storageClassName的PVC不太相同，集群会根据是否打开DefaultStorageClass允许插件对PVC进行不同的处理."

"PVC with no storageClassName is not quite the same and is treated differently by the cluster depending on whether the DefaultStorageClass admission plugin is turned on."

现在要选择哪个StorageClass?

由于您使用的是Minikube，因此我建议您坚持使用Minikube的minikube-hostpath.您可以检查是否可用:

Now which StorageClass to choose?

Since you're using Minikube i recommend you sticking with Minikube's minikube-hostpath. You can check if it's available:

$ kubectl get storageclass
NAME                 PROVISIONER                AGE
standard (default)   k8s.io/minikube-hostpath   2m36s

它支持动态配置并设置为默认StorageClass.

It supports dynamic provisioning and is set as default StorageClass.

尝试设置spec.storage.storageClassName: minikube-hostpath并相应地更新音量.

Try to set the spec.storage.storageClassName: minikube-hostpath and update your volumes accordingly.

这篇关于minikube安装本地目录上的KubeDB的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！