k8s：节点未就绪 - NodeHasSufficientMemory #kubernetes-the-hard-way

Question

我遵循 kubernetes-the-hard-way 创建 k8s 集群，因为我没有 ARM 设备，所以我使用 4 个 x86 架构的虚拟机。这是与指南唯一不同的地方。

所有步骤都很顺利，直到第 09 章-bootstrapping-kubernetes-workers，节点尚未准备好：

"kubectl get nodes \
  --kubeconfig admin.kubeconfig"
NAME     STATUS     ROLES    AGE   VERSION
node-0   NotReady   <none>   94s   v1.31.2
node-1   NotReady   <none>   98s   v1.31.2

通过describe节点进一步检查，根本原因是KubeletHasSufficientMemory

实际上，节点要有足够的内存，并且swap是关闭的。

root@node-0:~# free -m
               total        used        free      shared  buff/cache   available
Mem:            1967         869         356          26         920        1097
Swap:              0           0           0

root@server:~#  kubectl describe nodes --kubeconfig admin.kubeconfig
Name:               node-0
Roles:              <none>
Labels:             beta.kubernetes.io/arch=amd64
                    beta.kubernetes.io/os=linux
                    kubernetes.io/arch=amd64
                    kubernetes.io/hostname=node-0
                    kubernetes.io/os=linux
Annotations:        node.alpha.kubernetes.io/ttl: 0
                    volumes.kubernetes.io/controller-managed-attach-detach: true
CreationTimestamp:  Sun, 15 Dec 2024 04:56:26 -0600
Taints:             node.kubernetes.io/not-ready:NoSchedule
Unschedulable:      false
Lease:
  HolderIdentity:  node-0
  AcquireTime:     <unset>
  RenewTime:       Sun, 15 Dec 2024 05:12:08 -0600
Conditions:
  Type             Status  LastHeartbeatTime                 LastTransitionTime                Reason                       Message
  ----             ------  -----------------                 ------------------                ------                       -------
  MemoryPressure   False   Sun, 15 Dec 2024 05:11:55 -0600   Sun, 15 Dec 2024 04:56:26 -0600   KubeletHasSufficientMemory   kubelet has
 sufficient memory available
  DiskPressure     False   Sun, 15 Dec 2024 05:11:55 -0600   Sun, 15 Dec 2024 04:56:26 -0600   KubeletHasNoDiskPressure     kubelet has
 no disk pressure
  PIDPressure      False   Sun, 15 Dec 2024 05:11:55 -0600   Sun, 15 Dec 2024 04:56:26 -0600   KubeletHasSufficientPID      kubelet has
 sufficient PID available
  Ready            False   Sun, 15 Dec 2024 05:11:55 -0600   Sun, 15 Dec 2024 04:56:26 -0600   KubeletNotReady              container r
untime network not ready: NetworkReady=false reason:NetworkPluginNotReady message:Network plugin returns error: cni plugin not initiali
zed
Addresses:
  InternalIP:  192.168.122.26
  Hostname:    node-0
Capacity:
  cpu:                1
  ephemeral-storage:  19480400Ki

Answer 1

我找到原因了，不是内存资源问题。 实际错误是

Network plugin returns error: cni plugin not initialized

Ready            False   Sun, 15 Dec 2024 05:11:55 -0600   Sun, 15 Dec 2024 04:56:26 -0600   KubeletNotReady              container r
untime network not ready: NetworkReady=false reason:NetworkPluginNotReady message:Network plugin returns error: cni plugin not initiali

原来是我忘记了步骤：

创建桥接网络配置文件：

mv 10-bridge.conf 99-loopback.conf /etc/cni/net.d/

重复此步骤后，重新启动

containerd kubelet kube-proxy

节点状态为Ready。