016.Kubernetes二进制部署所有节点kube-proxy

一 部署 kube-proxy

kube-proxy 运行在所有节点上，它监听 apiserver 中 service 和 endpoint 的变化情况，创建路由规则以提供服务 IP 和负载均衡功能。

1.1 安装kube-proxy

提示：k8smaster01节点已下载相应二进制，可直接分发至node节点。

1.2 分发kube-proxy

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for all_ip in ${ALL_IPS[@]}
  4   do
  5     echo ">>> ${all_ip}"
  6     scp kubernetes/server/bin/kube-proxy root@${all_ip}:/opt/k8s/bin/
  7     ssh root@${all_ip} "chmod +x /opt/k8s/bin/*"
  8   done

1.3 创建kube-scheduler证书和私钥

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# cat > kube-proxy-csr.json <  3 {
  4   "CN": "system:kube-proxy",
  5   "key": {
  6     "algo": "rsa",
  7     "size": 2048
  8   },
  9   "names": [
 10     {
 11       "C": "CN",
 12       "ST": "Shanghai",
 13       "L": "Shanghai",
 14       "O": "k8s",
 15       "OU": "System"
 16     }
 17   ]
 18 }
 19 EOF
 20 #创建kube-scheduler的CA证书请求文件

解释：

• CN：指定该证书的 User 为 system:kube-proxy；
• 预定义的 RoleBinding system:node-proxier 将User system:kube-proxy 与 Role system:node-proxier 绑定，该 Role 授予了调用 kube-apiserver Proxy 相关 API 的权限；
• 该证书只会被 kube-proxy 当做 client 证书使用，所以 hosts 字段为空。

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# cfssl gencert -ca=/opt/k8s/work/ca.pem \
  3 -ca-key=/opt/k8s/work/ca-key.pem -config=/opt/k8s/work/ca-config.json \
  4 -profile=kubernetes kube-proxy-csr.json | cfssljson -bare kube-proxy		#生成CA密钥（ca-key.pem）和证书（ca.pem）

1.4 创建和分发kubeconfig

kube-proxy 使用 kubeconfig 文件访问 apiserver，该文件提供了 apiserver 地址、嵌入的 CA 证书和 kube-proxy 证书：

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# kubectl config set-cluster kubernetes \
  4   --certificate-authority=/opt/k8s/work/ca.pem \
  5   --embed-certs=true \
  6   --server=${KUBE_APISERVER} \
  7   --kubeconfig=kube-proxy.kubeconfig
  8 
  9 [root@k8smaster01 work]# kubectl config set-credentials kube-proxy \
 10   --client-certificate=kube-proxy.pem \
 11   --client-key=kube-proxy-key.pem \
 12   --embed-certs=true \
 13   --kubeconfig=kube-proxy.kubeconfig
 14 
 15 [root@k8smaster01 work]# kubectl config set-context default \
 16   --cluster=kubernetes \
 17   --user=kube-proxy \
 18   --kubeconfig=kube-proxy.kubeconfig
 19 
 20 [root@k8smaster01 work]# kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig
 21 
 22 [root@k8smaster01 ~]# cd /opt/k8s/work
 23 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
 24 [root@k8smaster01 work]# for node_name in ${NODE_NAMES[@]}
 25   do
 26     echo ">>> ${node_name}"
 27     scp kube-proxy.kubeconfig root@${node_name}:/etc/kubernetes/
 28   done

1.5 创建kube-proxy 配置文件

从 v1.10 开始，kube-proxy 部分参数可以配置文件中配置。可以使用 --write-config-to 选项生成该配置文件。

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# cat > kube-proxy-config.yaml.template <  3 kind: KubeProxyConfiguration
  4 apiVersion: kubeproxy.config.k8s.io/v1alpha1
  5 clientConnection:
  6   burst: 200
  7   kubeconfig: "/etc/kubernetes/kube-proxy.kubeconfig"
  8   qps: 100
  9 bindAddress: ##ALL_IP##
 10 healthzBindAddress: ##ALL_IP##:10256
 11 metricsBindAddress: ##ALL_IP##:10249
 12 enableProfiling: true
 13 clusterCIDR: ${CLUSTER_CIDR}
 14 hostnameOverride: ##ALL_NAME##
 15 mode: "ipvs"
 16 portRange: ""
 17 kubeProxyIPTablesConfiguration:
 18   masqueradeAll: false
 19 kubeProxyIPVSConfiguration:
 20   scheduler: rr
 21   excludeCIDRs: []
 22 EOF

解释：

• bindAddress: 监听地址；
• clientConnection.kubeconfig: 连接 apiserver 的 kubeconfig 文件；
• clusterCIDR: kube-proxy 根据 --cluster-cidr 判断集群内部和外部流量，指定 --cluster-cidr 或 --masquerade-all 选项后 kube-proxy 才会对访问 Service IP 的请求做 SNAT；
• hostnameOverride: 参数值必须与 kubelet 的值一致，否则 kube-proxy 启动后会找不到该 Node，从而不会创建任何 ipvs 规则；
• mode: 使用 ipvs 模式。

1.6 分发配置文件

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for (( i=0; i < 6; i++ ))
  4   do
  5     echo ">>> ${ALL_NAMES[i]}"
  6     sed -e "s/##ALL_NAME##/${ALL_NAMES[i]}/" -e "s/##ALL_IP##/${ALL_IPS[i]}/" kube-proxy-config.yaml.template > kube-proxy-config-${ALL_NAMES[i]}.yaml.template
  7     scp kube-proxy-config-${ALL_NAMES[i]}.yaml.template root@${ALL_NAMES[i]}:/etc/kubernetes/kube-proxy-config.yaml
  8   done

1.7 创建kube-proxy的systemd

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# cat > kube-proxy.service <  4 [Unit]
  5 Description=Kubernetes Kube-Proxy Server
  6 Documentation=https://github.com/GoogleCloudPlatform/kubernetes
  7 After=network.target
  8 
  9 [Service]
 10 WorkingDirectory=${K8S_DIR}/kube-proxy
 11 ExecStart=/opt/k8s/bin/kube-proxy \\
 12   --config=/etc/kubernetes/kube-proxy-config.yaml \\
 13   --logtostderr=true \\
 14   --v=2
 15 Restart=on-failure
 16 RestartSec=5
 17 LimitNOFILE=65536
 18 
 19 [Install]
 20 WantedBy=multi-user.target
 21 EOF

1.8 分发kube-proxy systemd

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for all_name in ${ALL_NAMES[@]}
  4   do
  5     echo ">>> ${all_name}"
  6     scp kube-proxy.service root@${all_name}:/etc/systemd/system/
  7   done						#分发system

二 启动并验证

2.1 启动kube-proxy 服务

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for all_ip in ${ALL_IPS[@]}
  4   do
  5     echo ">>> ${all_ip}"
  6     ssh root@${all_ip} "mkdir -p ${K8S_DIR}/kube-proxy"
  7     ssh root@${all_ip} "modprobe ip_vs_rr"
  8     ssh root@${all_ip} "systemctl daemon-reload && systemctl enable kube-proxy && systemctl restart kube-proxy"
  9   done						#启动服务前必须先创建工作目录

2.2 检查kube-proxy 服务

  1 [root@k8smaster01 ~]# source /opt/k8s/bin/environment.sh
  2 [root@k8smaster01 ~]# for all_ip in ${ALL_IPS[@]}
  3   do
  4     echo ">>> ${all_ip}"
  5     ssh root@${all_ip} "systemctl status kube-proxy|grep Active"
  6   done

2.3 查看监听端口

kube-proxy 监听 10249 和 10256 端口：

• 10249：对外提供 /metrics;
• 10256：对外提供 /healthz 的访问。

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for all_ip in ${ALL_IPS[@]}
  4   do
  5     echo ">>> ${all_ip}"
  6     ssh root@${all_ip} "sudo netstat -lnpt|grep kube-prox"
  7   done

2.4 查看ipvs 路由规则

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for all_ip in ${ALL_IPS[@]}
  4   do
  5     echo ">>> ${all_ip}"
  6     ssh root@${all_ip} "/usr/sbin/ipvsadm -ln"
  7   done

可见所有通过 https 访问 K8S SVC kubernetes 的请求都转发到 kube-apiserver 节点的 6443 端口。