Kubernetes集群部署—部署Worker节点（四）

文章目录

下面还是在Master Node上操作，即同时作为Worker Node

1、创建工作目录并拷贝二进制文件

在所有worker node创建工作目录：（node节点操作）

mkdir -p /opt/kubernetes/{bin,cfg,ssl,logs}

从master节点拷贝：（master节点操作）

cd /opt/tools/kubernetes/server/bin/
cp kubelet  kube-proxy /opt/kubernetes/bin/

scp kubelet  kube-proxy k8s-node1:/opt/kubernetes/bin/
scp kubelet  kube-proxy k8s-node2:/opt/kubernetes/bin/

2 部署kubelet （master节点操作）

2.1 创建配置文件

cat > /opt/kubernetes/cfg/kubelet.conf << EOF
KUBELET_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--hostname-override=k8s-master \\
--network-plugin=cni \\
--kubeconfig=/opt/kubernetes/cfg/kubelet.kubeconfig \\
--bootstrap-kubeconfig=/opt/kubernetes/cfg/bootstrap.kubeconfig \\
--config=/opt/kubernetes/cfg/kubelet-config.yml \\
--cert-dir=/opt/kubernetes/ssl \\
--pod-infra-container-image=mirrorgooglecontainers/pause-amd64:3.0"
EOF

–hostname-override：显示名称，集群中唯一
–network-plugin：启用CNI
–kubeconfig：空路径，会自动生成，后面用于连接apiserver
–bootstrap-kubeconfig：首次启动向apiserver申请证书
–config：配置参数文件
–cert-dir：kubelet证书生成目录
–pod-infra-container-image：管理Pod网络容器的镜像

2.2 配置参数文件

cat > /opt/kubernetes/cfg/kubelet-config.yml << EOF
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: 0.0.0.0
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS:
- 10.0.0.2
clusterDomain: cluster.local 
failSwapOn: false
authentication:
  anonymous:
    enabled: false
  webhook:
    cacheTTL: 2m0s
    enabled: true
  x509:
    clientCAFile: /opt/kubernetes/ssl/ca.pem 
authorization:
  mode: Webhook
  webhook:
    cacheAuthorizedTTL: 5m0s
    cacheUnauthorizedTTL: 30s
evictionHard:
  imagefs.available: 15%
  memory.available: 100Mi
  nodefs.available: 10%
  nodefs.inodesFree: 5%
maxOpenFiles: 1000000
maxPods: 110
EOF

2.3 生成bootstrap.kubeconfig文件

KUBE_APISERVER="https://10.20.17.20:6443" # apiserver IP:PORT
TOKEN="063e91e42837f2a2b36860457f515053" # 与token.csv里保持一致

cd /root/TLS/k8s

# 生成 kubelet bootstrap kubeconfig 配置文件
kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=bootstrap.kubeconfig
  
kubectl config set-credentials "kubelet-bootstrap" \
  --token=${TOKEN} \
  --kubeconfig=bootstrap.kubeconfig
  
kubectl config set-context default \
  --cluster=kubernetes \
  --user="kubelet-bootstrap" \
  --kubeconfig=bootstrap.kubeconfig
  
  
kubectl config use-context default --kubeconfig=bootstrap.kubeconfig

拷贝到配置文件路径：

cp /root/TLS/k8s/bootstrap.kubeconfig /opt/kubernetes/cfg

2.4 systemd管理kubelet

cat > /usr/lib/systemd/system/kubelet.service << EOF
[Unit]
Description=Kubernetes Kubelet
After=docker.service
[Service]
EnvironmentFile=/opt/kubernetes/cfg/kubelet.conf
ExecStart=/opt/kubernetes/bin/kubelet \$KUBELET_OPTS
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF

2.5 启动并设置开机启动

systemctl daemon-reload
systemctl start kubelet
systemctl enable kubelet

注：若无法启动，可通过查看系统日志排查问题原因：cat /var/log/messages

3 批准kubelet证书申请并加入集群

# 查看kubelet证书请求
[root@k8s-master ~]# kubectl get csr
NAME                                                   AGE     SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-LHEDjWtPT39E8gkKemznF7a5GgEfX4Y5Q34E-MgzJbw   9m53s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending

# 批准申请
kubectl certificate approve node-csr-LHEDjWtPT39E8gkKemznF7a5GgEfX4Y5Q34E-MgzJbw

# 查看节点
[root@k8s-master ~]# kubectl get node
NAME         STATUS     ROLES    AGE   VERSION
k8s-master   NotReady   <none>   21s   v1.18.3

注：由于网络插件还没有部署，节点会没有准备就绪 NotReady

4 部署kube-proxy （master节点操作）

4.1 创建配置文件

cat > /opt/kubernetes/cfg/kube-proxy.conf << EOF
KUBE_PROXY_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--config=/opt/kubernetes/cfg/kube-proxy-config.yml"
EOF

4.2 配置参数文件

cat > /opt/kubernetes/cfg/kube-proxy-config.yml << EOF
kind: KubeProxyConfiguration
apiVersion: kubeproxy.config.k8s.io/v1alpha1
bindAddress: 0.0.0.0
metricsBindAddress: 0.0.0.0:10249
clientConnection:
  kubeconfig: /opt/kubernetes/cfg/kube-proxy.kubeconfig
hostnameOverride: k8s-master
clusterCIDR: 10.0.0.0/24
EOF

4.3 生成kube-proxy.kubeconfig文件

生成kube-proxy证书：

# 切换工作目录
cd /root/TLS/k8s

# 创建证书请求文件
cat > kube-proxy-csr.json << EOF
{
  "CN": "system:kube-proxy",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing",
      "ST": "BeiJing",
      "O": "k8s",
      "OU": "System"
    }
  ]
}
EOF

# 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-proxy-csr.json | cfssljson -bare kube-proxy

# ls kube-proxy*pem
kube-proxy-key.pem  kube-proxy.pem

生成kubeconfig文件：


KUBE_APISERVER="https://10.20.17.20:6443"

cd /root/TLS/k8s

kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=kube-proxy.kubeconfig
  
kubectl config set-credentials kube-proxy \
  --client-certificate=./kube-proxy.pem \
  --client-key=./kube-proxy-key.pem \
  --embed-certs=true \
  --kubeconfig=kube-proxy.kubeconfig
  
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-proxy \
  --kubeconfig=kube-proxy.kubeconfig
  
  
kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig

拷贝到配置文件指定路径：

cp /root/TLS/k8s/kube-proxy.kubeconfig /opt/kubernetes/cfg/

4.4 systemd管理kube-proxy

cat > /usr/lib/systemd/system/kube-proxy.service << EOF
[Unit]
Description=Kubernetes Proxy
After=network.target
[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-proxy.conf
ExecStart=/opt/kubernetes/bin/kube-proxy \$KUBE_PROXY_OPTS
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF

4.5 启动并设置开机启动

systemctl daemon-reload
systemctl start kube-proxy
systemctl enable kube-proxy

5 部署CNI网络（master节点操作）

5.1 准备CNI二进制文件

下载地址：https://github.com/containernetworking/plugins/releases/download/v0.8.6/cni-plugins-linux-amd64-v0.8.6.tgz

5.2 解压二进制包并移动到默认工作目录

mkdir -p /opt/cni/bin
cd /opt/tools/
tar zxvf cni-plugins-linux-amd64-v0.8.6.tgz -C /opt/cni/bin

5.3 部署CNI网络

wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

# 若默认镜像地址无法访问，修改为docker hub镜像仓库。此处我们不进行修改
sed -i -r "s#quay.io/coreos/flannel:.*-amd64#lizhenliang/flannel:v0.12.0-amd64#g" kube-flannel.yml

生成flannel网络容器：

# kubectl apply -f kube-flannel.yml

# kubectl get pods -n kube-system
NAME                          READY   STATUS    RESTARTS   AGE
kube-flannel-ds-amd64-c4t2v   1/1     Running   0          25s

# kubectl get node
NAME         STATUS   ROLES    AGE   VERSION
k8s-master   Ready    <none>   36m   v1.18.3

部署好网络插件，Node准备就绪。

6 授权apiserver访问kubelet （master节点操作）

cat > apiserver-to-kubelet-rbac.yaml << EOF
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  annotations:
    rbac.authorization.kubernetes.io/autoupdate: "true"
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
  name: system:kube-apiserver-to-kubelet
rules:
  - apiGroups:
      - ""
    resources:
      - nodes/proxy
      - nodes/stats
      - nodes/log
      - nodes/spec
      - nodes/metrics
      - pods/log
    verbs:
      - "*"
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: system:kube-apiserver
  namespace: ""
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:kube-apiserver-to-kubelet
subjects:
  - apiGroup: rbac.authorization.k8s.io
    kind: User
    name: kubernetes
EOF

kubectl apply -f apiserver-to-kubelet-rbac.yaml

7 新增加Worker Node

7.1 拷贝已部署好的Node相关文件到新节点

master节点操作
在master节点将Worker Node涉及文件拷贝到新节点：node1 、node2

scp -r /opt/kubernetes k8s-node1:/opt/
scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service k8s-node1:/usr/lib/systemd/system
scp -r /opt/cni/ k8s-node1:/opt/
scp /opt/kubernetes/ssl/ca.pem k8s-node1:/opt/kubernetes/ssl

7.2 删除kubelet证书和kubeconfig文件

node节点操作

rm /opt/kubernetes/cfg/kubelet.kubeconfig 
rm -f /opt/kubernetes/ssl/kubelet*

注：这几个文件是证书申请审批后自动生成的，每个Node不同，必须删除重新生成。

7.3 修改主机名

node节点操作

vim /opt/kubernetes/cfg/kubelet.conf
--hostname-override=k8s-node1

vim /opt/kubernetes/cfg/kube-proxy-config.yml
hostnameOverride: k8s-node1

7.4 启动并设置开机启动

node 节点操作

systemctl daemon-reload
systemctl start kubelet
systemctl enable kubelet
systemctl start kube-proxy
systemctl enable kube-proxy

7.5 在Master上批准新Node kubelet证书申请

master节点操作

# kubectl get csr
NAME                                                   AGE   SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-LHEDjWtPT39E8gkKemznF7a5GgEfX4Y5Q34E-MgzJbw   68m   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Approved,Issued
node-csr-eFXMlBTEP1jYeRrMur_ZdpMeWyKmtyQ-A_LGOQZ74a0   57s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending

kubectl certificate approve node-csr-eFXMlBTEP1jYeRrMur_ZdpMeWyKmtyQ-A_LGOQZ74a0

7.6 查看Node状态

master节点操作

[root@k8s-master ~]# kubectl get node
NAME         STATUS   ROLES    AGE   VERSION
k8s-master   Ready    <none>   60m   v1.18.3
k8s-node1    Ready    <none>   62s   v1.18.3

注：若新加的节点状态为NotReady时，可使用journalctl -f -u kubelet 检查问题，若为以下报错：

 Container runtime network not ready: NetworkReady=false reason:NetworkPluginNotReady message:docker: network plugin is not ready: cni config uninitialized

此问题为网络插件没有准备好，我们可以执行命令docker images|grep flannel来查看flannel镜像是否已经成功拉取下来.经过排查,flannel镜像拉取的有点慢,稍等一会以后就可以了，或者手动执行命令下载镜像：docker pull quay.io/coreos/flannel:v0.12.0-amd64

若需要继续添加node节点2，同上操作即可，记得修改主机名！