Kubernetes mongodb 就绪探针失败

Question

我正在尝试运行 mongodb 的 helm 图表，但遇到了就绪/活跃度探测问题。稳定存储库中的 Mongodb Helm Chart 将安装 Pod 和服务。但吊舱因就绪探测而崩溃。我可以尝试删除它们，但我想知道为什么会发生这种情况。

helm install --name mongodb stable/mongodb

kubectl describe pod mongodb-5ff464b5b9-nnz5x

Containers:
  mongodb:
    Container ID:   docker://055f12c14992dc111ee8f0baff7faceafae6a16e518b27a174a7997408235afa
    Image:          docker.io/bitnami/mongodb:4.0.2-debian-9
    Image ID:       docker-pullable://bitnami/mongodb@sha256:6c050bf9063976e12aabb7bafcc7b2616df1e1dbbf19ac41b4799826abec92a3
    Port:           27017/TCP
    Host Port:      0/TCP
    State:          Waiting
      Reason:       CrashLoopBackOff
    Last State:     Terminated
      Reason:       Error
      Exit Code:    137
      Started:      Thu, 27 Sep 2018 17:54:01 -0400
      Finished:     Thu, 27 Sep 2018 17:55:50 -0400
    Ready:          False
    Restart Count:  6
    Liveness:       exec [mongo --eval db.adminCommand('ping')] delay=30s timeout=5s period=10s #success=1 #failure=6
    Readiness:      exec [mongo --eval db.adminCommand('ping')] delay=5s timeout=5s period=10s #success=1 #failure=6
    Environment:
      MONGODB_ROOT_PASSWORD:  <set to the key 'mongodb-root-password' in secret 'mongodb'>  Optional: false
      MONGODB_USERNAME:       
      MONGODB_DATABASE:       
      MONGODB_ENABLE_IPV6:    yes
      MONGODB_EXTRA_FLAGS:    
    Mounts:
      /bitnami/mongodb from data (rw)

在错误部分，我看到以下内容。我需要做什么才能打开集装箱港口吗？

connecting to: mongodb://127.0.0.1:27017
2018-09-27T21:43:04.664+0000 E QUERY    [js] Error: couldn't connect to server 127.0.0.1:27017, connection attempt failed: SocketException: Error connecting to 127.0.0.1:27017 :: caused by :: Connection refused :
connect@src/mongo/shell/mongo.js:257:13
@(connect):1:6
exception: connect failed
  Warning  Unhealthy  6m  kubelet, vm-b768f1df-3df6-4a79-50e5-9af633c6d9b9  Readiness probe failed: MongoDB shell version v4.0.2
connecting to: mongodb://127.0.0.1:27017
2018-09-27T21:43:14.670+0000 E QUERY    [js] Error: couldn't connect to server 127.0.0.1:27017, connection attempt failed: SocketException: Error connecting to 127.0.0.1:27017 :: caused by :: Connection refused :
connect@src/mongo/shell/mongo.js:257:13
@(connect):1:6
exception: connect failed
  Warning  Unhealthy  6m  kubelet, vm-b768f1df-3df6-4a79-50e5-9af633c6d9b9  Readiness probe failed: MongoDB shell version v4.0.2
connecting to: mongodb://127.0.0.1:27017
2018-09-27T21:43:24.657+0000 E QUERY    [js] Error: couldn't connect to server 127.0.0.1:27017, connection attempt failed: SocketException: Error connecting to 127.0.0.1:27017 :: caused by :: Connection refused :
connect@src/mongo/shell/mongo.js:257:13
@(connect):1:6
exception: connect failed

编辑1

来自 Pod 的日志我检查了日志，没有什么值得注意的

`kubectl logs mongodb-5ff464b5b9-nnz5x -p` 
------
Welcome to the Bitnami mongodb container
Subscribe to project updates by watching https://github.com/bitnami/bitnami-docker-mongodb
Submit issues and feature requests at https://github.com/bitnami/bitnami-docker-mongodb/issues

nami    INFO  Initializing mongodb
mongodb INFO  ==> Deploying MongoDB from scratch...
mongodb INFO  ==> No injected configuration files found. Creating default config files...

编辑2

在 GKE 上运行相同的 Helm Chart，我遇到了完全相同的问题

Events:
  Type     Reason                 Age              From                                                  Message
  ----     ------                 ----             ----                                                  -------
  Warning  FailedScheduling       1m (x4 over 1m)  default-scheduler                                     PersistentVolumeClaim is not bound: "mongodb-bitnami" (repeated 3 times)
  Normal   Scheduled              1m               default-scheduler                                     Successfully assigned mongodb-bitnami-7b65895fd7-xr6gg to gke-cluster-default-pool-bec82955-xmhz
  Normal   SuccessfulMountVolume  1m               kubelet, gke-cluster-default-pool-bec82955-xmhz  MountVolume.SetUp succeeded for volume "default-token-whl5w"
  Normal   SuccessfulMountVolume  1m               kubelet, gke-cluster-default-pool-bec82955-xmhz  MountVolume.SetUp succeeded for volume "pvc-ddda94dd-c2c1-11e8-b2f0-42010af00119"
  Normal   Pulling                1m               kubelet, gke-cluster-default-pool-bec82955-xmhz  pulling image "docker.io/bitnami/mongodb:4.0.2-debian-9"
  Normal   Pulled                 39s              kubelet, gke-cluster-default-pool-bec82955-xmhz  Successfully pulled image "docker.io/bitnami/mongodb:4.0.2-debian-9"
  Normal   Created                38s              kubelet, gke-cluster-default-pool-bec82955-xmhz  Created container
  Normal   Started                37s              kubelet, gke-cluster-default-pool-bec82955-xmhz  Started container
  Warning  Unhealthy              28s              kubelet, gke-cluster-default-pool-bec82955-xmhz  Readiness probe failed: MongoDB shell version v4.0.2
connecting to: mongodb://127.0.0.1:27017
2018-09-28T01:58:44.936+0000 E QUERY    [js] Error: couldn't connect to server 127.0.0.1:27017, connection attempt failed: SocketException: Error connecting to 127.0.0.1:27017 :: caused by :: Connection refused :
connect@src/mongo/shell/mongo.js:257:13
@(connect):1:6
exception: connect failed
  Warning  Unhealthy  20s  kubelet, gke-cluster-default-pool-bec82955-xmhz  Readiness probe failed: MongoDB shell version v4.0.2
connecting to: mongodb://127.0.0.1:27017
2018-09-28T01:58:52.114+0000 E QUERY    [js] Error: couldn't connect to server 127.0.0.1:27017, connection attempt failed: SocketException: Error connecting to 127.0.0.1:27017 :: caused by :: Connection refused :
connect@src/mongo/shell/mongo.js:257:13
@(connect):1:6
exception: connect failed

Answer 1

它与端口是否打开无关，看起来更像是 mongo 本身崩溃并且就绪探针失败。

您可以通过查看日志找到更多见解：

kubectl logs <pod-crashing-name> (-c <container-name-optionally)

您还可以 ssh 进入运行 pod 的节点并获取 docker 日志

docker ps -a | grep mongo
docker logs <container-id-that-crashed>