手动搭建k8s-1.16.6高可用集群之部署worker节点-部署kube-proxy组件

Myth丶恋晨 2023-05-21 07:08 12阅读 0赞

kube-proxy 运行在所有 worker 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。

本文档讲解部署 ipvs 模式的 kube-proxy 过程。

注意：如果没有特殊指明，本文档的所有操作**均在 k8s-01 节点上执行**，然后远程分发文件和执行命令。

下载和分发在部署master节点时已经做过，依赖包也在work节点中安装了，可以直接进入配置步骤。

## 一、创建 kube-proxy 证书 ##

cd /opt/k8s/work
    
    cat > kube-proxy-csr.json <<EOF { "CN": "system:kube-proxy", "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "ST": "BeiJing", "L": "BeiJing", "O": "k8s", "OU": "opsnull" } ] } EOF

*  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；

生成证书和私钥：

$ cd /opt/k8s/work
    
    $ cfssl gencert -ca=/opt/k8s/work/ca.pem \
      -ca-key=/opt/k8s/work/ca-key.pem \
      -config=/opt/k8s/work/ca-config.json \
      -profile=kubernetes  kube-proxy-csr.json | cfssljson -bare kube-proxy
      
    $ ls kube-proxy*

## 二、 创建和分发 kubeconfig 文件 ##

cd /opt/k8s/work
    source /opt/k8s/bin/environment.sh
    
    kubectl config set-cluster kubernetes \
      --certificate-authority=/opt/k8s/work/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

分发 kubeconfig 文件：

cat > deploy.sh << "EOF" #!/bin/bash cd /opt/k8s/work source /opt/k8s/bin/environment.sh for node_name in ${NODE_NAMES[@]} do echo ">>> ${node_name}" scp kube-proxy.kubeconfig root@${node_name}:/etc/kubernetes/ done EOF

## 三、 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，或者参考 [源代码的注释][Link 1]。

创建 kube-proxy config 文件模板：

cd /opt/k8s/work
    source /opt/k8s/bin/environment.sh
    
    cat > kube-proxy-config.yaml.template <<EOF kind: KubeProxyConfiguration apiVersion: kubeproxy.config.k8s.io/v1alpha1 clientConnection: burst: 200 kubeconfig: "/etc/kubernetes/kube-proxy.kubeconfig" qps: 100 bindAddress: ##NODE_IP## healthzBindAddress: ##NODE_IP##:10256 metricsBindAddress: ##NODE_IP##:10249 enableProfiling: true clusterCIDR: ${CLUSTER_CIDR} hostnameOverride: ##NODE_NAME## mode: "ipvs" portRange: "" iptables: masqueradeAll: false ipvs: scheduler: rr excludeCIDRs: [] EOF

*  `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；

为各节点创建和分发 kube-proxy 配置文件：

cat > deploy.sh << "EOF" #!/bin/bash cd /opt/k8s/work source /opt/k8s/bin/environment.sh for (( i=0; i < 3; i++ )) do echo ">>> ${NODE_NAMES[i]}" sed -e "s/##NODE_NAME##/${NODE_NAMES[i]}/" -e "s/##NODE_IP##/${NODE_IPS[i]}/" kube-proxy-config.yaml.template > kube-proxy-config-${NODE_NAMES[i]}.yaml.template scp kube-proxy-config-${NODE_NAMES[i]}.yaml.template root@${NODE_NAMES[i]}:/etc/kubernetes/kube-proxy-config.yaml done EOF

## 四、 创建和分发 kube-proxy systemd unit 文件 ##

cd /opt/k8s/work
    source /opt/k8s/bin/environment.sh
    
    cat > kube-proxy.service <<EOF [Unit] Description=Kubernetes Kube-Proxy Server Documentation=https://github.com/GoogleCloudPlatform/kubernetes After=network.target [Service] WorkingDirectory=${K8S_DIR}/kube-proxy ExecStart=/opt/k8s/bin/kube-proxy \\ --config=/etc/kubernetes/kube-proxy-config.yaml \\ --logtostderr=true \\ --v=2 Restart=on-failure RestartSec=5 LimitNOFILE=65536 [Install] WantedBy=multi-user.target EOF

分发 kube-proxy systemd unit 文件：

cat > deploy.sh << "EOF" #!/bin/bash cd /opt/k8s/work source /opt/k8s/bin/environment.sh for node_name in ${NODE_NAMES[@]} do echo ">>> ${node_name}" scp kube-proxy.service root@${node_name}:/etc/systemd/system/ done EOF

## 五、 启动 kube-proxy 服务 ##

cat > deploy.sh << "EOF" #!/bin/bash cd /opt/k8s/work source /opt/k8s/bin/environment.sh for node_ip in ${NODE_IPS[@]} do echo ">>> ${node_ip}" ssh root@${node_ip} "mkdir -p ${K8S_DIR}/kube-proxy" ssh root@${node_ip} "modprobe ip_vs_rr" ssh root@${node_ip} "systemctl daemon-reload && systemctl enable kube-proxy && systemctl restart kube-proxy" done EOF

## 六、检查启动结果 ##

cat > deploy.sh << "EOF" #!/bin/bash cd /opt/k8s/work source /opt/k8s/bin/environment.sh for node_ip in ${NODE_IPS[@]} do echo ">>> ${node_ip}" ssh root@${node_ip} "systemctl status kube-proxy|grep Active" done EOF

输出结果如下：

$ ./deploy.sh
    >>> 192.168.0.71
       Active: active (running) since Mon 2020-04-27 15:49:46 CST; 9s ago
    >>> 192.168.0.72
       Active: active (running) since Mon 2020-04-27 15:49:47 CST; 8s ago
    >>> 192.168.0.73
       Active: active (running) since Mon 2020-04-27 15:49:48 CST; 8s ago

确保状态为 `active (running)`，否则如下命令查看日志，确认原因：

journalctl -u kube-proxy

## 七、 查看监听端口 ##

$ sudo netstat -lnpt|grep kube-prox
    tcp        0      0 192.168.0.71:10249      0.0.0.0:*               LISTEN      47812/kube-proxy    
    tcp        0      0 192.168.0.71:10256      0.0.0.0:*               LISTEN      47812/kube-proxy

## 八、 查看 ipvs 路由规则 ##

cat > deploy.sh << "EOF" #!/bin/bash cd /opt/k8s/work source /opt/k8s/bin/environment.sh for node_ip in ${NODE_IPS[@]} do echo ">>> ${node_ip}" ssh root@${node_ip} "/usr/sbin/ipvsadm -ln" done EOF

输出结果如下：

$ ./deploy.sh 
    >>> 192.168.0.71
    IP Virtual Server version 1.2.1 (size=4096)
    Prot LocalAddress:Port Scheduler Flags
      -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
    TCP  10.254.0.1:443 rr
      -> 192.168.0.71:6443            Masq    1      0          0         
      -> 192.168.0.72:6443            Masq    1      0          0         
      -> 192.168.0.73:6443            Masq    1      0          0         
    >>> 192.168.0.72
    IP Virtual Server version 1.2.1 (size=4096)
    Prot LocalAddress:Port Scheduler Flags
      -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
    TCP  10.254.0.1:443 rr
      -> 192.168.0.71:6443            Masq    1      0          0         
      -> 192.168.0.72:6443            Masq    1      0          0         
      -> 192.168.0.73:6443            Masq    1      0          0         
    >>> 192.168.0.73
    IP Virtual Server version 1.2.1 (size=4096)
    Prot LocalAddress:Port Scheduler Flags
      -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
    TCP  10.254.0.1:443 rr
      -> 192.168.0.71:6443            Masq    1      0          0         
      -> 192.168.0.72:6443            Masq    1      0          0         
      -> 192.168.0.73:6443            Masq    1      0          0

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。

[Link 1]: https://github.com/kubernetes/kubernetes/blob/release-1.14/pkg/proxy/apis/config/types.go