安装笔记K8S 1.15.0版本遇到的一些错误汇总（部分参考网络上经验，基本可以解决问题）
1.1.1 Kubelet启动报错：node "kube-master1" not found
今天在通过kubeadm安装kubernetes v1.13.1集群时，发现有一台机器始终安装不成功，总是在启动kubelet时失败，报错信息如下：
问题现象：
[root@master taoweizhong]# systemctl status kubelet -l
● kubelet.service - kubelet: The Kubernetes Node Agent
Loaded: loaded (/usr/lib/systemd/system/kubelet.service; enabled; vendor preset: disabled)
Drop-In: /usr/lib/systemd/system/kubelet.service.d
└─10-kubeadm.conf
Active: active (running) since Wed 2019-07-31 05:37:08 PDT; 2min 8s ago
Docs: https://kubernetes.io/docs/
Main PID: 6161 (kubelet)
Tasks: 16
Memory: 82.0M
CGroup: /system.slice/kubelet.service
└─6161 /usr/bin/kubelet --bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf --config=/var/lib/kubelet/config.yaml --cgroup-driver=cgroupfs --network-plugin=cni --pod-infra-container-image=k8s.gcr.io/pause:3.1 --fail-swap-on=false
Jul 31 05:39:16 master kubelet[6161]: E0731 05:39:16.008683 6161 kubelet.go:2248] node "master" not found
Jul 31 05:39:16 master kubelet[6161]: E0731 05:39:16.109488 6161 kubelet.go:2248] node "master" not found
Jul 31 05:39:16 master kubelet[6161]: E0731 05:39:16.210368 6161 kubelet.go:2248] node "master" not found
初始化kubelet时设置的master IP错误，导致kubelet无法连接master的API Server上，检查kubelet.conf配置文件，发现server: https:// 192.168.135.139:6443这项配置非当前机器的IP（原因是我使用动态IP导致）：
[root@master taoweizhong]# cat /etc/kubernetes/kubelet.conf
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: server: https://192.168.135.143:6443
name: kubernetes
contexts:
- context:
cluster: kubernetes
user: system:node:master
name: system:node:master@kubernetes
current-context: system:node:master@kubernetes
修改如下文件中配置正确的IP地址
[root@master kubernetes]# vim admin.conf
[root@master kubernetes]# vim controller-manager.conf
[root@master kubernetes]# vim kubelet.conf
[root@master kubernetes]# vim scheduler.conf
1.1.2 ETCD启动错误定位
ETCD启动错误定位
配置docker网络flannel时，配置etcd的key的时候出现以下错误
Error: client: etcd cluster is
unavailable or misconfigured; error #0: dial tcp 127.0.0.1:4001: getsockopt:
connection refused
; error #1: dial tcp 127.0.0.1:2379: getsockopt: connection refused
error #0: dial tcp 127.0.0.1:4001:
getsockopt: connection refused
error #1: dial tcp 127.0.0.1:2379: getsockopt: connection refused
解决办法：
修改etcd的配置文件：
vim /etc/etcd/etcd.conf
在 第6行，后面配置http://127.0.0.1:2379，与本机自己进行通信， ETCD_LISTEN_CLIENT_URLS="http:// 192.168.135.143:2379,http://127.0.0.1:2379"
然后重启etcd服务
1.1.3 NetworkPluginNotReady message:docker: network plugin is not ready: cni config uninitialized
Jul 31 05:59:03 master kubelet[22561]: W0731 05:59:03.364199 22561 cni.go:213] Unable to update cni config: No networks found in /etc/cni/net.d
Jul 31 05:59:04 master kubelet[22561]: E0731 05:59:04.542692 22561 kubelet.go:2169] Container runtime network not ready: NetworkReady=false reason:NetworkPluginNotReady message:docker: network plugin is not ready: cni config uninitialized
部署flannel作为k8s中的网络插件，yaml文件都大小同异。
但在要注意以下细节。
以前，只需要前面master判断。
现在也需要有not-ready状态了。
tolerations:
- key: node-role.kubernetes.io/master
operator: Exists
effect: NoSchedule
- key: node.kubernetes.io/not-ready
operator: Exists
effect: NoSchedule
1.1.4 主节点The connection to the server localhost:8080 was refused - did you specify the right host or port?
root@master taoweizhong]# kubectl get cs
The connection to the server localhost:8080 was refused - did you specify the right host or port?
原因：kubenetes master没有与本机绑定，集群初始化的时候没有设置
解决办法：执行以下命令 export KUBECONFIG=/etc/kubernetes/admin.conf
/etc/ admin.conf这个文件主要是集群初始化的时候用来传递参数的
1.1.5 从节点The connection to the server localhost:8080 was refused - did you specify the right host or port?
在Kubernetes的从节点上运行命令kubectl出现了如下错误
# kubectl get pod
The connection to the server localhost:8080 was refused - did you specify the right host or port?
问题原因是kubectl命令需使用kubernetes-admin来运行，解决方法如下，将主节点中的/etc/kubernetes/admin.conf文件拷贝到从节点相同目录下，然后配置环境变量：
echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.bash_profile
可生效
source ~/.bash_profile
[root@master kubernetes]# scp admin.conf root@192.168.135.130:/home/taoweizhong
现在可以用kubectl get node 查看有多少节点了 , 如果想在node节点上使用kubectl 命令需要把 k8s-master 上 /etc/kubernetes/admin.conf 文件copy到几点机器上并使用 export KUBECONFIG=/etc/kubernetes/admin.conf, 这个在初始化的时候已经提到, 可以用scp 命令拷贝
1.1.6 yum安装提示Another app is currently holding the yum lock; waiting for it to exit...
在Linux系统中使用yum安装软件时，提示yum处于锁定状态
1 Another app is currently holding the yum lock; waiting for it to exit...
可通过强制关闭yum进程
1 #rm -f /var/run/yum.pid
1.1.7 Get http://localhost:8080/api?timeout=32s: dial tcp [::1]:8080: connect: connection refused
t@slave2 taoweizhong]# kubectl apply -f kube-flannel.yml
unable to recognize "kube-flannel.yml": Get http://localhost:8080/api?timeout=32s: dial tcp [::1]:8080: connect: connection refused
1.1.8 从节点Unit kubelet.service entered failed state.
kubelet.service - kubelet: The Kubernetes Node Agent
Loaded: loaded (/usr/lib/systemd/system/kubelet.service; enabled; vendor preset: disabled)
Drop-In: /usr/lib/systemd/system/kubelet.service.d
└─10-kubeadm.conf
Active: activating (auto-restart) (Result: exit-code) since Thu 2019-08-01 07:53:40 PDT; 6s ago
Docs: https://kubernetes.io/docs/
Process: 23003 ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_CONFIG_ARGS $KUBELET_KUBEADM_ARGS $KUBELET_EXTRA_ARGS (code=exited, status=255)
Main PID: 23003 (code=exited, status=255)
Aug 01 07:53:40 slave2 systemd[1]: kubelet.service: main process exited, code=exited, status=255/n/a
Aug 01 07:53:40 slave2 systemd[1]: Unit kubelet.service entered failed state.
Aug 01 07:53:40 slave2 systemd[1]: kubelet.service failed.
[root@slave2 taoweizhong]#
1.1.9 从节点 Error response from daemon: error creating overlay mount to
Aug 02 06:13:59 slave2 kubelet[15376]: E0802 06:13:59.567319 15376 pod_workers.go:190] Error syncing pod 6286750b-83ea-4c93-a895-f03a7d3ac8f6 ("kube-proxy-6m2hd_kube-system(6286750b-83ea-4c93-a895-f03a7d3ac8f6)"), skipping: failed to "CreatePodSandbox" for "kube-proxy-6m2hd_kube-system(6286750b-83ea-4c93-a895-f03a7d3ac8f6)" with CreatePodSandboxError: "CreatePodSandbox for pod \"kube-proxy-6m2hd_kube-system(6286750b-83ea-4c93-a895-f03a7d3ac8f6)\" failed: rpc error: code = Unknown desc = failed to create a sandbox for pod \"kube-proxy-6m2hd\": Error response from daemon: error creating overlay mount to /var/lib/docker/overlay2/458f364c092810a4ce67b80279af2f9de926d5caf0d639c46130e6876b2aca59-init/merged: no such file or directory"
在网上搜索一番后，一个可行的方案如下(改变storage driver类型， 禁用selinux):
停止docker服务
systemctl stop docker
清理镜像 rm -rf /var/lib/docker
修改存储类型
vi /etc/sysconfig/docker-storage
DOCKER_STORAGE_OPTIONS="--storage-driver overlay"
1.1.10 running with swap on is not supported. Please disable swap
1 [ERROR Swap]: running with swap on is not supported. Please disable swap
2 [ERROR SystemVerification]: missing cgroups: memory
3 [ERROR ImagePull]: failed to pull image [k8s.gcr.io/kube-apiserver-amd64:v1.12.2]
建议不使用： swapoff -a
注释掉/etc/fstab下swap挂载后安装成功
1.1.11 Container "02599322c0f1ad7113d60d19836b1e91a83a4bdb5f5fe7c6adabee409f88ddd4" not found in pod's containers
重置kubernetes服务，重置网络。删除网络配置，link
kubeadm reset
systemctl stop kubelet
systemctl stop docker
rm -rf /var/lib/cni/
rm -rf /var/lib/kubelet/*
rm -rf /etc/cni/
ifconfig cni0 down
ifconfig flannel.1 down
ifconfig docker0 down
ip link delete cni0
ip link delete flannel.1
systemctl start docker
