docker - 执行 kubeadm 重置后，Kubernetes 无法为 pod 设置网络

Question

我用 kubeadm init 初始化了 Kubernetes，在我使用 kubeadm reset 重置它之后，我发现 --pod-network-cidr 是错误的。更正后，我尝试使用 kubeadm 再次像这样初始化 Kubernetes:

kubeadm init --use-kubernetes-version v1.5.1 --external-etcd endpoints=http://10.111.125.131:2379 --pod-network-cidr=10.244.0.0/16

然后我在节点上遇到了一些错误

12月 28 15:30:55 ydtf-node-137 kubelet[13333]: E1228 15:30:55.838700   13333 cni.go:255] Error adding network: no IP addresses available in network: cbr0
12月 28 15:30:55 ydtf-node-137 kubelet[13333]: E1228 15:30:55.838727   13333 cni.go:209] Error while adding to cni network: no IP addresses available in network: cbr0
12月 28 15:30:55 ydtf-node-137 kubelet[13333]: E1228 15:30:55.838781   13333 docker_manager.go:2201] Failed to setup network for pod "test-701078429-tl3j2_default(6945191b-ccce-11e6-b53d-78acc0f9504e)" using network plugins "cni": no IP addresses available in network: cbr0; Skipping pod  
12月 28 15:30:56 ydtf-node-137 kubelet[13333]: E1228 15:30:56.205596   13333 pod_workers.go:184] Error syncing pod 6945191b-ccce-11e6-b53d-78acc0f9504e, skipping: failed to "SetupNetwork" for "test-701078429-tl3j2_default" with SetupNetworkError: "Failed to setup network for pod \"test-701078429-tl3j2_default(6945191b-ccce-11e6-b53d-78acc0f9504e)\" using network plugins \"cni\": no IP addresses available in network: cbr0; Skipping pod"

或

Dec 29 10:20:02 ydtf-node-137 kubelet: E1229 10:20:02.065142   22259 pod_workers.go:184] Error syncing pod 235cd9c6-cd6c-11e6-a9cd-78acc0f9504e, skipping: failed to "SetupNetwork" for "test-701078429-zmkdf_default" with SetupNetworkError: "Failed to setup network for pod \"test-701078429-zmkdf_default(235cd9c6-cd6c-11e6-a9cd-78acc0f9504e)\" using network plugins \"cni\": \"cni0\" already has an IP address different from 10.244.1.1/24; Skipping pod"

为什么我不能为新的 pod 创建网络？

顺便说一句，我使用 flannel 作为网络提供商，它工作正常。

[root@ydtf-master-131 k8s151]# kubectl get pods --all-namespaces -o wide
NAMESPACE     NAME                                      READY     STATUS                       RESTARTS   AGE       IP               NODE
default       test-701078429-tl3j2                      0/1       ContainerCreating   0          2h        <none>           ydtf-node-137
kube-system   dummy-2088944543-hd7b7                    1/1       Running             0          2h        10.111.125.131   ydtf-master-131
kube-system   kube-apiserver-ydtf-master-131            1/1       Running             7          2h        10.111.125.131   ydtf-master-131
kube-system   kube-controller-manager-ydtf-master-131   1/1       Running             0          2h        10.111.125.131   ydtf-master-131
kube-system   kube-discovery-1769846148-bjgp8           1/1       Running             0          2h        10.111.125.131   ydtf-master-131
kube-system   kube-dns-2924299975-q8x2m                 4/4       Running             0          2h        10.244.0.3       ydtf-master-131 
kube-system   kube-flannel-ds-3fsjh                     2/2       Running             0          2h        10.111.125.137   ydtf-node-137
kube-system   kube-flannel-ds-89r72                     2/2       Running             0          2h        10.111.125.131   ydtf-master-131
kube-system   kube-proxy-7w8c4                          1/1       Running             0          2h        10.111.125.137   ydtf-node-137
kube-system   kube-proxy-jk6z6                          1/1       Running             0          2h        10.111.125.131   ydtf-master-131
kube-system   kube-scheduler-ydtf-master-131            1/1       Running             0          2h        10.111.125.131   ydtf-master-131

Answer 1

我想通了，如果你通过kubeadm init重新初始化kubernetes时更改--pod-network-cidr，你应该删除一些自动创建的东西，只是在再次执行 kubeadm init 之前，请按照以下步骤操作:

1. 在主节点和节点上执行 kubeadm reset。

2. 执行etcdctl rm --recursive registry重置etcd中的数据。

3. rm -rf/var/lib/cni 在主节点和节点上

4. rm -rf/run/flannel 在主节点和节点上

5. rm -rf/etc/cni 在主节点和节点上

6. ifconfig cni0 down 在主节点和节点上

7. brctl delbr cni0 在主节点和节点上

现在，我的 Kubernetes 工作正常 :)