kubernetes - 无法在 Pod 中启动多个容器 - 同步 pod 时出错，正在跳过

Question

我的kubectl版本

Client Version: version.Info{Major:"1", Minor:"2", GitVersion:"v1.2.4", GitCommit:"3eed1e3be6848b877ff80a93da3785d9034d0a4f", GitTreeState:"clean"}
Server Version: version.Info{Major:"1", Minor:"2", GitVersion:"v1.2.4", GitCommit:"3eed1e3be6848b877ff80a93da3785d9034d0a4f", GitTreeState:"clean"}

我关注了Creating Multi-Container Pods

启动 pod 后，一个容器已启动，但其他容器已启动。

kubectl 获取 Pod

NAME                    READY     STATUS             RESTARTS   AGE
redis-django            1/2       CrashLoopBackOff   9          22m

然后我做了kubectl描述redis-django。在底部我看到同步 Pod 时出错，正在跳过错误

  31m   <invalid>       150     {kubelet 172.25.30.21}  spec.containers{frontend}       Warning BackOff         Back-off restarting failed docker container
  25m   <invalid>       121     {kubelet 172.25.30.21}                                  Warning FailedSync      Error syncing pod, skipping: failed to "StartContainer" for "frontend" with CrashLoopBackOff: "Back-off 5m0s restarting failed container=frontend pod=redis-django_default(9f35ffcd-391e-11e6-b160-0022195df673)"

我该如何解决这个错误？任何帮助!

谢谢!

操作系统:Ubuntu 14

更新

之前我使用了下面的 yaml 文件，该文件位于 Creating Multi-Container Pods

apiVersion: v1
kind: Pod
metadata:
  name: redis-django
  labels:
    app: web
spec:
  containers:
    - name: key-value-store
      image: redis
      ports:
        - containerPort: 6379
    - name: frontend
      image: django
      ports:
        - containerPort: 8000

frontend 容器未启动。然后我将 yaml 文件更改为两个具有不同名称和端口的 redis 容器。但是，结果是相同的(同步 pod 时出错，跳过)

后来我将 yaml 文件更改为只有一个 django 容器。此 Pod 状态 CrashLoopBackOff 和 同步 Pod 时出错，正在跳过

更新2

I tail -f/var/log/upstart/kublet.log，它给出了相同的错误。 Kubelet 不断尝试启动容器，但没有启动!

I0623 12:15:13.943046     445 manager.go:2050] Back-off 5m0s restarting failed container=key-value-store pod=redis-django_default(94683d3c-392e-11e6-b160-0022195df673)
E0623 12:15:13.943100     445 pod_workers.go:138] Error syncing pod 94683d3c-392e-11e6-b160-0022195df673, skipping: failed to "StartContainer" for "key-value-store" with CrashLoopBackOff: "Back-off 5m0s restarting failed container=key-value-store pod=redis-django_default(94683d3c-392e-11e6-b160-0022195df673)"

更新3

root@vm1:~/kubernetes/cluster/ubuntu/binaries# kubectl describe pod redis-django
Name:           redis-django
Namespace:      default
Node:           192.168.1.10/192.168.1.10
Start Time:     Thu, 23 Jun 2016 22:58:03 -0700
Labels:         app=web
Status:         Running
IP:             172.16.20.2
Controllers:    <none>
Containers:
  key-value-store:
    Container ID:       docker://8dbdd6826c354243964f0306427082223d3da49bf2aaf30e15961ea00362fe42
    Image:              redis
    Image ID:           docker://sha256:4465e4bcad80b5b43cef0bace96a8ef0a55c0050be439c1fb0ecd64bc0b8cce4
    Port:               6379/TCP
    QoS Tier:
      cpu:              BestEffort
      memory:           BestEffort
    State:              Running
      Started:          Thu, 23 Jun 2016 22:58:10 -0700
    Ready:              True
    Restart Count:      0
    Environment Variables:
  frontend:
    Container ID:       docker://9c89602739abe7331b3beb3a79e92a7cc42e2a7e40e11618413c8bcfd0afbc16
    Image:              django
    Image ID:           docker://sha256:0cb63b45e2b9a8de5763fc9c98b79c38b6217df718238251a21c8c4176fb3d68
    Port:               8000/TCP
    QoS Tier:
      cpu:              BestEffort
      memory:           BestEffort
    State:              Terminated
      Reason:           Completed
      Exit Code:        0
      Started:          Thu, 23 Jun 2016 22:58:41 -0700
      Finished:         Thu, 23 Jun 2016 22:58:41 -0700
    Last State:         Terminated
      Reason:           Completed
      Exit Code:        0
      Started:          Thu, 23 Jun 2016 22:58:22 -0700
      Finished:         Thu, 23 Jun 2016 22:58:22 -0700
    Ready:              False
    Restart Count:      2
    Environment Variables:
Conditions:
  Type          Status
  Ready         False 
Volumes:
  default-token-0oq7p:
    Type:       Secret (a volume populated by a Secret)
    SecretName: default-token-0oq7p
Events:
  FirstSeen     LastSeen        Count   From                    SubobjectPath                           Type            Reason           Message
  ---------     --------        -----   ----                    -------------                           --------        ------           -------
  49s           49s             1       {default-scheduler }                                            Normal          Scheduled        Successfully assigned redis-django to 192.168.1.10
  48s           48s             1       {kubelet 192.168.1.10}  spec.containers{key-value-store}        Normal          Pulling          pulling image "redis"
  43s           43s             1       {kubelet 192.168.1.10}  spec.containers{key-value-store}        Normal          Pulled           Successfully pulled image "redis"
  43s           43s             1       {kubelet 192.168.1.10}  spec.containers{key-value-store}        Normal          Created          Created container with docker id 8dbdd6826c35
  42s           42s             1       {kubelet 192.168.1.10}  spec.containers{key-value-store}        Normal          Started          Started container with docker id 8dbdd6826c35
  37s           37s             1       {kubelet 192.168.1.10}  spec.containers{frontend}               Normal          Started          Started container with docker id 3872ceae75d4
  37s           37s             1       {kubelet 192.168.1.10}  spec.containers{frontend}               Normal          Created          Created container with docker id 3872ceae75d4
  30s           30s             1       {kubelet 192.168.1.10}  spec.containers{frontend}               Normal          Created          Created container with docker id d97b99b6780c
  30s           30s             1       {kubelet 192.168.1.10}  spec.containers{frontend}               Normal          Started          Started container with docker id d97b99b6780c
  29s           29s             1       {kubelet 192.168.1.10}                                          Warning         FailedSync       Error syncing pod, skipping: failed to "StartContainer" for "frontend" with CrashLoopBackOff: "Back-off 10s restarting failed container=frontend pod=redis-django_default(9d0a966a-39d0-11e6-9027-000c293d51ab)"

  42s   16s     3       {kubelet 192.168.1.10}  spec.containers{frontend}       Normal  Pulling         pulling image "django"
  11s   11s     1       {kubelet 192.168.1.10}  spec.containers{frontend}       Normal  Started         Started container with docker id 9c89602739ab
  38s   11s     3       {kubelet 192.168.1.10}  spec.containers{frontend}       Normal  Pulled          Successfully pulled image "django"
  11s   11s     1       {kubelet 192.168.1.10}  spec.containers{frontend}       Normal  Created         Created container with docker id 9c89602739ab
  29s   10s     2       {kubelet 192.168.1.10}  spec.containers{frontend}       Warning BackOff         Back-off restarting failed docker container
  10s   10s     1       {kubelet 192.168.1.10}                                  Warning FailedSync      Error syncing pod, skipping: failed to "StartContainer" for "frontend" with CrashLoopBackOff: "Back-off 20s restarting failed container=frontend pod=redis-django_default(9d0a966a-39d0-11e6-9027-000c293d51ab)"

对于容器前端:不显示任何日志消息

root@vm1:~/kubernetes/cluster/ubuntu/binaries# kubectl logs redis-django -p -c frontend
root@vm1:~/kubernetes/cluster/ubuntu/binaries# kubectl logs redis-django -p -c key-value-store
Error from server: previous terminated container "key-value-store" in pod "redis-django" not found
root@vm1:~/kubernetes/cluster/ubuntu/binaries# docker ps
CONTAINER ID        IMAGE                                COMMAND                  CREATED             STATUS              PORTS               NAMES
8dbdd6826c35        redis                                "docker-entrypoint.sh"   2 minutes ago       Up 2 minutes                            k8s_key-value-store.f572c2d_redis-django_default_9d0a966a-39d0-11e6-9027-000c293d51ab_11101aea
8995bbf9f4f4        gcr.io/google_containers/pause:2.0   "/pause"                 2 minutes ago       Up 2 minutes                            k8s_POD.48e5231f_redis-django_default_9d0a966a-39d0-11e6-9027-000c293d51ab_c00025b0
root@vm1:~/kubernetes/cluster/ubuntu/binaries#

Answer 1

啊...您的 django 容器在启动后自动退出，没有任何错误消息，这是预期的。

django 镜像带有一个默认命令 python3。如果不覆盖 pod yaml 文件中的 command/args，容器将立即退出。

doc您遵循的只是尝试展示如何在 Pod 中创建多个容器，但该示例并不现实，并且未设置有效的应用程序。欢迎针对 https://github.com/kubernetes/kubernetes.github.io 提交 github 问题