Kubernetes：如何debuggingCrashLoopBackOff
我有以下设置：
omg/telperion hub上的docker image omg/telperion一个kubernetes集群（有4个节点，每个节点有50GB RAM）和大量资源
我跟着教程把图像从dockerhub拉到kubernetes
SERVICE_NAME=telperion DOCKER_SERVER="https://index.docker.io/v1/" DOCKER_USERNAME=username DOCKER_PASSWORD=password DOCKER_EMAIL="omg@whatever.com" # Create secret kubectl create secret docker-registry dockerhub --docker-server=$DOCKER_SERVER --docker-username=$DOCKER_USERNAME --docker-password=$DOCKER_PASSWORD --docker-email=$DOCKER_EMAIL # Create service yaml echo "apiVersion: v1 \n\ kind: Pod \n\ metadata: \n\ name: ${SERVICE_NAME} \n\ spec: \n\ containers: \n\ - name: ${SERVICE_NAME} \n\ image: omg/${SERVICE_NAME} \n\ imagePullPolicy: Always \n\ command: [ \"echo\",\"done deploying $SERVICE_NAME\" ] \n\ imagePullSecrets: \n\ - name: dockerhub" > $SERVICE_NAME.yaml # Deploy to kubernetes kubectl create -f $SERVICE_NAME.yaml
这导致Pod进入CrashLoopBackoff
docker run -it -p8080:9546 omg/telperion工作正常。
所以我的问题是这个可debugging吗？如果是的话，我该如何debugging？
一些日志：
kubectl get nodes NAME STATUS AGE VERSION k8s-agent-adb12ed9-0 Ready 22h v1.6.6 k8s-agent-adb12ed9-1 Ready 22h v1.6.6 k8s-agent-adb12ed9-2 Ready 22h v1.6.6 k8s-master-adb12ed9-0 Ready,SchedulingDisabled 22h v1.6.6
。
kubectl get pods NAME READY STATUS RESTARTS AGE telperion 0/1 CrashLoopBackOff 10 28m
。
kubectl describe pod telperion Name: telperion Namespace: default Node: k8s-agent-adb12ed9-2/10.240.0.4 Start Time: Wed, 21 Jun 2017 10:18:23 +0000 Labels: <none> Annotations: <none> Status: Running IP: 10.244.1.4 Controllers: <none> Containers: telperion: Container ID: docker://c2dd021b3d619d1d4e2afafd7a71070e1e43132563fdc370e75008c0b876d567 Image: omg/telperion Image ID: docker-pullable://omg/telperion@sha256:c7e3beb0457b33cd2043c62ea7b11ae44a5629a5279a88c086ff4853828a6d96 Port: Command: echo done deploying telperion State: Waiting Reason: CrashLoopBackOff Last State: Terminated Reason: Completed Exit Code: 0 Started: Wed, 21 Jun 2017 10:19:25 +0000 Finished: Wed, 21 Jun 2017 10:19:25 +0000 Ready: False Restart Count: 3 Environment: <none> Mounts: /var/run/secrets/kubernetes.io/serviceaccount from default-token-n7ll0 (ro) Conditions: Type Status Initialized True Ready False PodScheduled True Volumes: default-token-n7ll0: Type: Secret (a volume populated by a Secret) SecretName: default-token-n7ll0 Optional: false QoS Class: BestEffort Node-Selectors: <none> Tolerations: <none> Events: FirstSeen LastSeen Count From SubObjectPath Type Reason Message --------- -------- ----- ---- ------------- -------- ------ ------- 1m 1m 1 default-scheduler Normal Scheduled Successfully assigned telperion to k8s-agent-adb12ed9-2 1m 1m 1 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Normal Created Created container with id d9aa21fd16b682698235e49adf80366f90d02628e7ed5d40a6e046aaaf7bf774 1m 1m 1 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Normal Started Started container with id d9aa21fd16b682698235e49adf80366f90d02628e7ed5d40a6e046aaaf7bf774 1m 1m 1 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Normal Started Started container with id c6c8f61016b06d0488e16bbac0c9285fed744b933112fd5d116e3e41c86db919 1m 1m 1 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Normal Created Created container with id c6c8f61016b06d0488e16bbac0c9285fed744b933112fd5d116e3e41c86db919 1m 1m 2 kubelet, k8s-agent-adb12ed9-2 Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "telperion" with CrashLoopBackOff: "Back-off 10s restarting failed container=telperion pod=telperion_default(f4e36a12-566a-11e7-99a6-000d3aa32f49)" 1m 1m 1 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Normal Started Started container with id 3b911f1273518b380bfcbc71c9b7b770826c0ce884ac876fdb208e7c952a4631 1m 1m 1 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Normal Created Created container with id 3b911f1273518b380bfcbc71c9b7b770826c0ce884ac876fdb208e7c952a4631 1m 1m 2 kubelet, k8s-agent-adb12ed9-2 Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "telperion" with CrashLoopBackOff: "Back-off 20s restarting failed container=telperion pod=telperion_default(f4e36a12-566a-11e7-99a6-000d3aa32f49)" 1m 50s 4 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Normal Pulling pulling image "omg/telperion" 47s 47s 1 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Normal Started Started container with id c2dd021b3d619d1d4e2afafd7a71070e1e43132563fdc370e75008c0b876d567 1m 47s 4 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Normal Pulled Successfully pulled image "omg/telperion" 47s 47s 1 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Normal Created Created container with id c2dd021b3d619d1d4e2afafd7a71070e1e43132563fdc370e75008c0b876d567 1m 9s 8 kubelet, k8s-agent-adb12ed9-2 spec.containers{telperion} Warning BackOff Back-off restarting failed container 46s 9s 4 kubelet, k8s-agent-adb12ed9-2 Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "telperion" with CrashLoopBackOff: "Back-off 40s restarting failed container=telperion pod=telperion_default(f4e36a12-566a-11e7-99a6-000d3aa32f49)"
编辑1：master上的kubelet报告的错误：
journalctl -u kubelet
。
Jun 21 10:28:49 k8s-master-ADB12ED9-0 docker[1622]: E0621 10:28:49.798140 1809 fsHandler.go:121] failed to collect filesystem stats - rootDiskErr: du command failed on /var/lib/docker/overlay/5cfff16d670f2df6520360595d7858fb5d16607b6999a88e5dcbc09e1e7ab9ce with output Jun 21 10:28:49 k8s-master-ADB12ED9-0 docker[1622]: , stderr: du: cannot access '/var/lib/docker/overlay/5cfff16d670f2df6520360595d7858fb5d16607b6999a88e5dcbc09e1e7ab9ce/merged/proc/13122/task/13122/fd/4': No such file or directory Jun 21 10:28:49 k8s-master-ADB12ED9-0 docker[1622]: du: cannot access '/var/lib/docker/overlay/5cfff16d670f2df6520360595d7858fb5d16607b6999a88e5dcbc09e1e7ab9ce/merged/proc/13122/task/13122/fdinfo/4': No such file or directory Jun 21 10:28:49 k8s-master-ADB12ED9-0 docker[1622]: du: cannot access '/var/lib/docker/overlay/5cfff16d670f2df6520360595d7858fb5d16607b6999a88e5dcbc09e1e7ab9ce/merged/proc/13122/fd/3': No such file or directory Jun 21 10:28:49 k8s-master-ADB12ED9-0 docker[1622]: du: cannot access '/var/lib/docker/overlay/5cfff16d670f2df6520360595d7858fb5d16607b6999a88e5dcbc09e1e7ab9ce/merged/proc/13122/fdinfo/3': No such file or directory Jun 21 10:28:49 k8s-master-ADB12ED9-0 docker[1622]: - exit status 1, rootInodeErr: <nil>, extraDiskErr: <nil>
编辑2：更多的日志
kubectl logs $SERVICE_NAME -p done deploying telperion
您可以通过访问您的豆荚日志
kubectl logs [podname] -p
-p选项将读取以前（崩溃）实例的日志
如果崩溃来自应用程序，那么应该在那里有有用的日志。