010.Kubernetes二进制部署kube-controller-manager

一部署高可用kube-controller-manager

1.1 高可用kube-controller-manager介绍

本实验部署一个三实例 kube-controller-manager 的集群，启动后将通过竞争选举机制产生一个 leader 节点，其它节点为阻塞状态。当 leader 节点不可用时，阻塞的节点将再次进行选举产生新的 leader 节点，从而保证服务的可用性。

为保证通信安全，本文档先生成 x509 证书和私钥，kube-controller-manager 在如下两种情况下使用该证书：

与 kube-apiserver 的安全端口通信;
在安全端口(https，10252) 输出 prometheus 格式的 metrics。

1.2 创建kube-controller-manager证书和私钥

  1 [root@k8smaster01 ~]# cd /opt/k8s/work

  2 [root@k8smaster01 work]# cat > kube-controller-manager-csr.json <<EOF

  3 {

  4   "CN": "system:kube-controller-manager",

  5   "hosts": [

  6     "127.0.0.1",

  7     "172.24.8.71",

  8     "172.24.8.72",

  9     "172.24.8.73"

 10   ],

 11   "key": {

 12     "algo": "rsa",

 13     "size": 2048

 14   },

 15   "names": [

 16     {

 17       "C": "CN",

 18       "ST": "Shanghai",

 19       "L": "Shanghai",

 20       "O": "system:kube-controller-manager",

 21       "OU": "System"

 22     }

 23   ]

 24 }

 25 EOF

 26 #创建kube-controller-manager的CA证书请求文件

解释：

hosts 列表包含所有 kube-controller-manager 节点 IP；

CN 和 O 均为 system:kube-controller-manager，kubernetes 内置的 ClusterRoleBindings system:kube-controller-manager 赋予 kube-controller-manager 工作所需的权限。

  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-controller-manager-csr.json | cfssljson -bare kube-controller-manager	#生成CA密钥（ca-key.pem）和证书（ca.pem）

1.3 分发证书和私钥

  1 [root@k8smaster01 ~]# cd /opt/k8s/work

  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh

  3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]}

  4   do

  5     echo ">>> ${master_ip}"

  6     scp kube-controller-manager*.pem root@${master_ip}:/etc/kubernetes/cert/

  7   done

1.4 创建和分发kubeconfig

kube-controller-manager 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-controller-manager 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-controller-manager.kubeconfig

  8

  9 [root@k8smaster01 work]# kubectl config set-credentials system:kube-controller-manager \

 10   --client-certificate=kube-controller-manager.pem \

 11   --client-key=kube-controller-manager-key.pem \

 12   --embed-certs=true \

 13   --kubeconfig=kube-controller-manager.kubeconfig

 14

 15 [root@k8smaster01 work]# kubectl config set-context system:kube-controller-manager \

 16   --cluster=kubernetes \

 17   --user=system:kube-controller-manager \

 18   --kubeconfig=kube-controller-manager.kubeconfig

 19

 20 [root@k8smaster01 work]# kubectl config use-context system:kube-controller-manager --kubeconfig=kube-controller-manager.kubeconfig

 21

 22 [root@k8smaster01 ~]# cd /opt/k8s/work

 23 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh

 24 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]}

 25   do

 26     echo ">>> ${master_ip}"

 27     scp kube-controller-manager.kubeconfig root@${master_ip}:/etc/kubernetes/

 28   done

1.5 创建kube-controller-manager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-controller-manager.service.template <<EOF

  4 [Unit]

  5 Description=Kubernetes Controller Manager

  6 Documentation=https://github.com/GoogleCloudPlatform/kubernetes

  7

  8 [Service]

  9 WorkingDirectory=${K8S_DIR}/kube-controller-manager

 10 ExecStart=/opt/k8s/bin/kube-controller-manager \\

 11   --profiling \\

 12   --cluster-name=kubernetes \\

 13   --controllers=*,bootstrapsigner,tokencleaner \\

 14   --kube-api-qps=1000 \\

 15   --kube-api-burst=2000 \\

 16   --leader-elect \\

 17   --use-service-account-credentials\\

 18   --concurrent-service-syncs=2 \\

 19   --bind-address=##MASTER_IP## \\

 20   --secure-port=10252 \\

 21   --tls-cert-file=/etc/kubernetes/cert/kube-controller-manager.pem \\

 22   --tls-private-key-file=/etc/kubernetes/cert/kube-controller-manager-key.pem \\

 23   --port=0 \\

 24   --authentication-kubeconfig=/etc/kubernetes/kube-controller-manager.kubeconfig \\

 25   --client-ca-file=/etc/kubernetes/cert/ca.pem \\

 26   --requestheader-allowed-names="" \\

 27   --requestheader-client-ca-file=/etc/kubernetes/cert/ca.pem \\

 28   --requestheader-extra-headers-prefix="X-Remote-Extra-" \\

 29   --requestheader-group-headers=X-Remote-Group \\

 30   --requestheader-username-headers=X-Remote-User \\

 31   --authorization-kubeconfig=/etc/kubernetes/kube-controller-manager.kubeconfig \\

 32   --cluster-signing-cert-file=/etc/kubernetes/cert/ca.pem \\

 33   --cluster-signing-key-file=/etc/kubernetes/cert/ca-key.pem \\

 34   --experimental-cluster-signing-duration=8760h \\

 35   --horizontal-pod-autoscaler-sync-period=10s \\

 36   --concurrent-deployment-syncs=10 \\

 37   --concurrent-gc-syncs=30 \\

 38   --node-cidr-mask-size=24 \\

 39   --service-cluster-ip-range=${SERVICE_CIDR} \\

 40   --pod-eviction-timeout=6m \\

 41   --terminated-pod-gc-threshold=10000 \\

 42   --root-ca-file=/etc/kubernetes/cert/ca.pem \\

 43   --service-account-private-key-file=/etc/kubernetes/cert/ca-key.pem \\

 44   --kubeconfig=/etc/kubernetes/kube-controller-manager.kubeconfig \\

 45   --logtostderr=true \\

 46   --v=2

 47 Restart=on-failure

 48 RestartSec=5

 49

 50 [Install]

 51 WantedBy=multi-user.target

 52 EOF

1.6 分发systemd

  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 < 3; i++ ))

  4   do

  5     sed -e "s/##MASTER_NAME##/${MASTER_NAMES[i]}/" -e "s/##MASTER_IP##/${MASTER_IPS[i]}/" kube-controller-manager.service.template > kube-controller-manager-${MASTER_IPS[i]}.service

  6   done						#修正相应IP

  7 [root@k8smaster01 work]# ls kube-controller-manager*.service

  8 [root@k8smaster01 ~]# cd /opt/k8s/work

  9 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh

 10 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]}

 11   do

 12     echo ">>> ${master_ip}"

 13     scp kube-controller-manager-${master_ip}.service root@${master_ip}:/etc/systemd/system/kube-controller-manager.service

 14   done						#分发system

二启动并验证

2.1 启动kube-controller-manager 服务

  1 [root@k8smaster01 ~]# cd /opt/k8s/work

  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh

  3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]}

  4   do

  5     echo ">>> ${master_ip}"

  6     ssh root@${master_ip} "mkdir -p ${K8S_DIR}/kube-controller-manager"

  7     ssh root@${master_ip} "systemctl daemon-reload && systemctl enable kube-controller-manager && systemctl restart kube-controller-manager"

  8   done

2.2 检查kube-controller-manager 服务

  1 [root@k8smaster01 ~]# source /opt/k8s/bin/environment.sh

  2 [root@k8smaster01 ~]# for master_ip in ${MASTER_IPS[@]}

  3   do

  4     echo ">>> ${master_ip}"

  5     ssh root@${master_ip} "systemctl status kube-controller-manager|grep Active"

  6   done

2.3 查看输出的 metrics

  1 [root@k8smaster01 ~]# curl -s --cacert /opt/k8s/work/ca.pem --cert /opt/k8s/work/admin.pem --key /opt/k8s/work/admin-key.pem https://172.24.8.71:10252/metrics |head

注意：以上命令在 kube-controller-manager 节点上执行。

2.4 查看权限

  1 [root@k8smaster01 ~]# kubectl describe clusterrole system:kube-controller-manager

ClusteRole system:kube-controller-manager 的权限很小，只能创建 secret、serviceaccount 等资源对象，各 controller 的权限分散到 ClusterRole system:controller:XXX 中。

当在 kube-controller-manager 的启动参数中添加 --use-service-account-credentials=true 参数，这样 main controller 会为各 controller 创建对应的 ServiceAccount XXX-controller。内置的 ClusterRoleBinding system:controller:XXX 将赋予各 XXX-controller ServiceAccount 对应的 ClusterRole system:controller:XXX 权限。

  1 [root@k8smaster01 ~]# kubectl get clusterrole|grep controller

如deployment controller：

  1 [root@k8smaster01 ~]# kubectl describe clusterrole system:controller:deployment-controller

2.5 查看当前leader

  1 [root@k8smaster01 ~]# kubectl get endpoints kube-controller-manager --namespace=kube-system  -o yaml

kubelet 认证和授权：https://kubernetes.io/docs/admin/kubelet-authentication-authorization/#kubelet-authorization

巴特西

010.Kubernetes二进制部署kube-controller-manager

一部署高可用kube-controller-manager

1.1 高可用kube-controller-manager介绍

1.2 创建kube-controller-manager证书和私钥

1.3 分发证书和私钥

1.4 创建和分发kubeconfig

1.5 创建kube-controller-manager的systemd

1.6 分发systemd

二启动并验证

2.1 启动kube-controller-manager 服务

2.2 检查kube-controller-manager 服务

2.3 查看输出的 metrics

2.4 查看权限

2.5 查看当前leader

最新文章

热门文章

巴特西

010.Kubernetes二进制部署kube-controller-manager

一 部署高可用kube-controller-manager

1.1 高可用kube-controller-manager介绍

1.2 创建kube-controller-manager证书和私钥

1.3 分发证书和私钥

1.4 创建和分发kubeconfig

1.5 创建kube-controller-manager的systemd

1.6 分发systemd

二 启动并验证

2.1 启动kube-controller-manager 服务

2.2 检查kube-controller-manager 服务

2.3 查看输出的 metrics

2.4 查看权限

2.5 查看当前leader

最新文章

热门文章

一部署高可用kube-controller-manager

二启动并验证