009.Kubernetes二進位制部署kube-apiserver
阿新 • • 發佈:2019-11-17
一 部署master節點
1.1 master節點服務
kubernetes master 節點執行如下元件:- kube-apiserver
- kube-scheduler
- kube-controller-manager
- kube-nginx
1.2 安裝Kubernetes
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# wget https://dl.k8s.io/v1.14.2/kubernetes-server-linux-amd64.tar.gz 3 [root@k8smaster01 work]# tar -xzvf kubernetes-server-linux-amd64.tar.gz 4 [root@k8smaster01 work]# cd kubernetes 5 [root@k8smaster01 kubernetes]# tar -xzvf kubernetes-src.tar.gz
1.3 分發Kubernetes
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 ">>> ${master_ip}" 6 scp kubernetes/server/bin/{apiextensions-apiserver,cloud-controller-manager,kube-apiserver,kube-controller-manager,kube-proxy,kube-scheduler,kubeadm,kubectl,kubelet,mounter} root@${master_ip}:/opt/k8s/bin/ 7 ssh root@${master_ip} "chmod +x /opt/k8s/bin/*" 8 done
二 部署高可用kube-apiserver
2.1 高可用apiserver介紹
本實驗部署一個三例項 kube-apiserver 叢集的步驟,它們通過 kube-nginx 進行代理訪問,從而保證服務可用性。2.2 建立Kubernetes證書和私鑰
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# cat > kubernetes-csr.json <<EOF 3 { 4 "CN": "kubernetes", 5 "hosts": [ 6 "127.0.0.1", 7 "172.24.8.71", 8 "172.24.8.72", 9 "172.24.8.73", 10 "${CLUSTER_KUBERNETES_SVC_IP}", 11 "kubernetes", 12 "kubernetes.default", 13 "kubernetes.default.svc", 14 "kubernetes.default.svc.cluster", 15 "kubernetes.default.svc.cluster.local." 16 ], 17 "key": { 18 "algo": "rsa", 19 "size": 2048 20 }, 21 "names": [ 22 { 23 "C": "CN", 24 "ST": "Shanghai", 25 "L": "Shanghai", 26 "O": "k8s", 27 "OU": "System" 28 } 29 ] 30 } 31 EOF 32 #建立Kubernetes的CA證書請求檔案解釋: hosts 欄位指定授權使用該證書的 IP 和域名列表,這裡列出了 master 節點 IP、kubernetes 服務的 IP 和域名; kubernetes 服務 IP 是 apiserver 自動建立的,一般是 --service-cluster-ip-range 引數指定的網段的第一個IP,後續可以通過下面命令獲取:
1 # kubectl get svc kubernetes
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 kubernetes-csr.json | cfssljson -bare kubernetes #生成CA金鑰(ca-key.pem)和證書(ca.pem)
2.3 分發證書和私鑰
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 /etc/kubernetes/cert" 7 scp kubernetes*.pem root@${master_ip}:/etc/kubernetes/cert/ 8 done
2.4 建立加密配置檔案
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh 3 [root@k8smaster01 work]# cat > encryption-config.yaml <<EOF 4 kind: EncryptionConfig 5 apiVersion: v1 6 resources: 7 - resources: 8 - secrets 9 providers: 10 - aescbc: 11 keys: 12 - name: key1 13 secret: ${ENCRYPTION_KEY} 14 - identity: {} 15 EOF
2.5 分發加密配置檔案
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 ">>> ${master_ip}" 6 scp encryption-config.yaml root@${master_ip}:/etc/kubernetes/ 7 done
2.6 建立審計策略檔案
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh 3 [root@k8smaster01 work]# cat > audit-policy.yaml <<EOF 4 apiVersion: audit.k8s.io/v1beta1 5 kind: Policy 6 rules: 7 # The following requests were manually identified as high-volume and low-risk, so drop them. 8 - level: None 9 resources: 10 - group: "" 11 resources: 12 - endpoints 13 - services 14 - services/status 15 users: 16 - 'system:kube-proxy' 17 verbs: 18 - watch 19 20 - level: None 21 resources: 22 - group: "" 23 resources: 24 - nodes 25 - nodes/status 26 userGroups: 27 - 'system:nodes' 28 verbs: 29 - get 30 31 - level: None 32 namespaces: 33 - kube-system 34 resources: 35 - group: "" 36 resources: 37 - endpoints 38 users: 39 - 'system:kube-controller-manager' 40 - 'system:kube-scheduler' 41 - 'system:serviceaccount:kube-system:endpoint-controller' 42 verbs: 43 - get 44 - update 45 46 - level: None 47 resources: 48 - group: "" 49 resources: 50 - namespaces 51 - namespaces/status 52 - namespaces/finalize 53 users: 54 - 'system:apiserver' 55 verbs: 56 - get 57 58 # Don't log HPA fetching metrics. 59 - level: None 60 resources: 61 - group: metrics.k8s.io 62 users: 63 - 'system:kube-controller-manager' 64 verbs: 65 - get 66 - list 67 68 # Don't log these read-only URLs. 69 - level: None 70 nonResourceURLs: 71 - '/healthz*' 72 - /version 73 - '/swagger*' 74 75 # Don't log events requests. 76 - level: None 77 resources: 78 - group: "" 79 resources: 80 - events 81 82 # node and pod status calls from nodes are high-volume and can be large, don't log responses for expected updates from nodes 83 - level: Request 84 omitStages: 85 - RequestReceived 86 resources: 87 - group: "" 88 resources: 89 - nodes/status 90 - pods/status 91 users: 92 - kubelet 93 - 'system:node-problem-detector' 94 - 'system:serviceaccount:kube-system:node-problem-detector' 95 verbs: 96 - update 97 - patch 98 99 - level: Request 100 omitStages: 101 - RequestReceived 102 resources: 103 - group: "" 104 resources: 105 - nodes/status 106 - pods/status 107 userGroups: 108 - 'system:nodes' 109 verbs: 110 - update 111 - patch 112 113 # deletecollection calls can be large, don't log responses for expected namespace deletions 114 - level: Request 115 omitStages: 116 - RequestReceived 117 users: 118 - 'system:serviceaccount:kube-system:namespace-controller' 119 verbs: 120 - deletecollection 121 122 # Secrets, ConfigMaps, and TokenReviews can contain sensitive & binary data, 123 # so only log at the Metadata level. 124 - level: Metadata 125 omitStages: 126 - RequestReceived 127 resources: 128 - group: "" 129 resources: 130 - secrets 131 - configmaps 132 - group: authentication.k8s.io 133 resources: 134 - tokenreviews 135 # Get repsonses can be large; skip them. 136 - level: Request 137 omitStages: 138 - RequestReceived 139 resources: 140 - group: "" 141 - group: admissionregistration.k8s.io 142 - group: apiextensions.k8s.io 143 - group: apiregistration.k8s.io 144 - group: apps 145 - group: authentication.k8s.io 146 - group: authorization.k8s.io 147 - group: autoscaling 148 - group: batch 149 - group: certificates.k8s.io 150 - group: extensions 151 - group: metrics.k8s.io 152 - group: networking.k8s.io 153 - group: policy 154 - group: rbac.authorization.k8s.io 155 - group: scheduling.k8s.io 156 - group: settings.k8s.io 157 - group: storage.k8s.io 158 verbs: 159 - get 160 - list 161 - watch 162 163 # Default level for known APIs 164 - level: RequestResponse 165 omitStages: 166 - RequestReceived 167 resources: 168 - group: "" 169 - group: admissionregistration.k8s.io 170 - group: apiextensions.k8s.io 171 - group: apiregistration.k8s.io 172 - group: apps 173 - group: authentication.k8s.io 174 - group: authorization.k8s.io 175 - group: autoscaling 176 - group: batch 177 - group: certificates.k8s.io 178 - group: extensions 179 - group: metrics.k8s.io 180 - group: networking.k8s.io 181 - group: policy 182 - group: rbac.authorization.k8s.io 183 - group: scheduling.k8s.io 184 - group: settings.k8s.io 185 - group: storage.k8s.io 186 187 # Default level for all other requests. 188 - level: Metadata 189 omitStages: 190 - RequestReceived 191 EOF
2.7 分發策略檔案
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 ">>> ${master_ip}" 6 scp audit-policy.yaml root@${master_ip}:/etc/kubernetes/audit-policy.yaml 7 done
2.8 建立訪問 metrics-server的證書和金鑰
1 [root@k8smaster01 ~]# cd /opt/k8s/work 2 [root@k8smaster01 work]# cat > proxy-client-csr.json <<EOF 3 { 4 "CN": "aggregator", 5 "hosts": [], 6 "key": { 7 "algo": "rsa", 8 "size": 2048 9 }, 10 "names": [ 11 { 12 "C": "CN", 13 "ST": "Shanghai", 14 "L": "Shanghai", 15 "O": "k8s", 16 "OU": "System" 17 } 18 ] 19 } 20 EOF 21 #建立metrics-server的CA證書請求檔案解釋: CN 名稱需要位於 kube-apiserver 的 --requestheader-allowed-names 引數中,否則後續訪問 metrics 時會提示許可權不足。
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 proxy-client-csr.json | cfssljson -bare proxy-client #生成CA金鑰(ca-key.pem)和證書(ca.pem)
2.9 分發證書和私鑰
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 ">>> ${master_ip}" 6 scp proxy-client*.pem root@${master_ip}:/etc/kubernetes/cert/ 7 done
2.10 建立kube-apiserver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-apiserver.service.template <<EOF 4 [Unit] 5 Description=Kubernetes API Server 6 Documentation=https://github.com/GoogleCloudPlatform/kubernetes 7 After=network.target 8 9 [Service] 10 WorkingDirectory=${K8S_DIR}/kube-apiserver 11 ExecStart=/opt/k8s/bin/kube-apiserver \\ 12 --advertise-address=##MASTER_IP## \\ 13 --default-not-ready-toleration-seconds=360 \\ 14 --default-unreachable-toleration-seconds=360 \\ 15 --feature-gates=DynamicAuditing=true \\ 16 --max-mutating-requests-inflight=2000 \\ 17 --max-requests-inflight=4000 \\ 18 --default-watch-cache-size=200 \\ 19 --delete-collection-workers=2 \\ 20 --encryption-provider-config=/etc/kubernetes/encryption-config.yaml \\ 21 --etcd-cafile=/etc/kubernetes/cert/ca.pem \\ 22 --etcd-certfile=/etc/kubernetes/cert/kubernetes.pem \\ 23 --etcd-keyfile=/etc/kubernetes/cert/kubernetes-key.pem \\ 24 --etcd-servers=${ETCD_ENDPOINTS} \\ 25 --bind-address=##MASTER_IP## \\ 26 --secure-port=6443 \\ 27 --tls-cert-file=/etc/kubernetes/cert/kubernetes.pem \\ 28 --tls-private-key-file=/etc/kubernetes/cert/kubernetes-key.pem \\ 29 --insecure-port=0 \\ 30 --audit-dynamic-configuration \\ 31 --audit-log-maxage=15 \\ 32 --audit-log-maxbackup=3 \\ 33 --audit-log-maxsize=100 \\ 34 --audit-log-mode=batch \\ 35 --audit-log-truncate-enabled \\ 36 --audit-log-batch-buffer-size=20000 \\ 37 --audit-log-batch-max-size=2 \\ 38 --audit-log-path=${K8S_DIR}/kube-apiserver/audit.log \\ 39 --audit-policy-file=/etc/kubernetes/audit-policy.yaml \\ 40 --profiling \\ 41 --anonymous-auth=false \\ 42 --client-ca-file=/etc/kubernetes/cert/ca.pem \\ 43 --enable-bootstrap-token-auth \\ 44 --requestheader-allowed-names="aggregator" \\ 45 --requestheader-client-ca-file=/etc/kubernetes/cert/ca.pem \\ 46 --requestheader-extra-headers-prefix="X-Remote-Extra-" \\ 47 --requestheader-group-headers=X-Remote-Group \\ 48 --requestheader-username-headers=X-Remote-User \\ 49 --service-account-key-file=/etc/kubernetes/cert/ca.pem \\ 50 --authorization-mode=Node,RBAC \\ 51 --runtime-config=api/all=true \\ 52 --enable-admission-plugins=NodeRestriction \\ 53 --allow-privileged=true \\ 54 --apiserver-count=3 \\ 55 --event-ttl=168h \\ 56 --kubelet-certificate-authority=/etc/kubernetes/cert/ca.pem \\ 57 --kubelet-client-certificate=/etc/kubernetes/cert/kubernetes.pem \\ 58 --kubelet-client-key=/etc/kubernetes/cert/kubernetes-key.pem \\ 59 --kubelet-https=true \\ 60 --kubelet-timeout=10s \\ 61 --proxy-client-cert-file=/etc/kubernetes/cert/proxy-client.pem \\ 62 --proxy-client-key-file=/etc/kubernetes/cert/proxy-client-key.pem \\ 63 --service-cluster-ip-range=${SERVICE_CIDR} \\ 64 --service-node-port-range=${NODE_PORT_RANGE} \\ 65 --logtostderr=true \\ 66 --v=2 67 Restart=on-failure 68 RestartSec=10 69 Type=notify 70 LimitNOFILE=65536 71 72 [Install] 73 WantedBy=multi-user.target 74 EOF解釋:
- --advertise-address:apiserver 對外通告的 IP(kubernetes 服務後端節點 IP);
- --default-*-toleration-seconds:設定節點異常相關的閾值;
- --max-*-requests-inflight:請求相關的最大閾值;
- --etcd-*:訪問 etcd 的證書和 etcd 伺服器地址;
- --experimental-encryption-provider-config:指定用於加密 etcd 中 secret 的配置;
- --bind-address: https 監聽的 IP,不能為 127.0.0.1,否則外界不能訪問它的安全埠 6443;
- --secret-port:https 監聽埠;
- --insecure-port=0:關閉監聽 http 非安全埠(8080);
- --tls-*-file:指定 apiserver 使用的證書、私鑰和 CA 檔案;
- --audit-*:配置審計策略和審計日誌檔案相關的引數;
- --client-ca-file:驗證 client (kue-controller-manager、kube-scheduler、kubelet、kube-proxy 等)請求所帶的證書;
- --enable-bootstrap-token-auth:啟用 kubelet bootstrap 的 token 認證;
- --requestheader-*:kube-apiserver 的 aggregator layer 相關的配置引數,proxy-client & HPA 需要使用;
- --requestheader-client-ca-file:用於簽名 --proxy-client-cert-file 和 --proxy-client-key-file 指定的證書;在啟用了 metric aggregator 時使用;
- --requestheader-allowed-names:不能為空,值為逗號分割的 --proxy-client-cert-file 證書的 CN 名稱,這裡設定為 "aggregator";
- --service-account-key-file:簽名 ServiceAccount Token 的公鑰檔案,kube-controller-manager 的 --service-account-private-key-file 指定私鑰檔案,兩者配對使用;
- --runtime-config=api/all=true: 啟用所有版本的 APIs,如 autoscaling/v2alpha1;
- --authorization-mode=Node,RBAC、--anonymous-auth=false: 開啟 Node 和 RBAC 授權模式,拒絕未授權的請求;
- --enable-admission-plugins:啟用一些預設關閉的 plugins;
- --allow-privileged:執行執行 privileged 許可權的容器;
- --apiserver-count=3:指定 apiserver 例項的數量;
- --event-ttl:指定 events 的儲存時間;
- --kubelet-*:如果指定,則使用 https 訪問 kubelet APIs;需要為證書對應的使用者(上面 kubernetes*.pem 證書的使用者為 kubernetes) 使用者定義 RBAC 規則,否則訪問 kubelet API 時提示未授權;
- --proxy-client-*:apiserver 訪問 metrics-server 使用的證書;
- --service-cluster-ip-range: 指定 Service Cluster IP 地址段;
- --service-node-port-range: 指定 NodePort 的埠範圍。
1 [root@zhangjun-k8s01 1.8+]# kubectl top nodes 2 Error from server (Forbidden): nodes.metrics.k8s.io is forbidden: User "aggregator" cannot list resource "nodes" in API group "metrics.k8s.io" at the cluster scope 3
2.11 分發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##/${MASTER_IPS[i]}/" kube-apiserver.service.template > kube-apiserver-${MASTER_IPS[i]}.service 6 done 7 [root@k8smaster01 work]# ls kube-apiserver*.service #替換相應的IP 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 ">>> ${master_ip}" 13 scp kube-apiserver-${master_ip}.service root@${master_ip}:/etc/systemd/system/kube-apiserver.service 14 done #分發systemd
三 啟動並驗證
3.1 啟動kube-apiserver服務
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} "mkdir -p ${K8S_DIR}/kube-apiserver" 6 ssh root@${master_ip} "systemctl daemon-reload && systemctl enable kube-apiserver && systemctl restart kube-apiserver" 7 done
3.2 檢查kube-apiserver服務
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-apiserver |grep 'Active:'" 6 done
3.3 檢視kube-apiserver寫入etcd的資料
1 [root@k8smaster01 ~]# source /opt/k8s/bin/environment.sh 2 [root@k8smaster01 ~]# ETCDCTL_API=3 etcdctl \ 3 --endpoints=${ETCD_ENDPOINTS} \ 4 --cacert=/opt/k8s/work/ca.pem \ 5 --cert=/opt/k8s/work/etcd.pem \ 6 --key=/opt/k8s/work/etcd-key.pem \ 7 get /registry/ --prefix --keys-only
3.4 檢查叢集資訊
1 [root@k8smaster01 ~]# kubectl cluster-info 2 [root@k8smaster01 ~]# kubectl get all --all-namespaces 3 [root@k8smaster01 ~]# kubectl get componentstatuses 4 [root@k8smaster01 ~]# sudo netstat -lnpt|grep kube #檢查 kube-apiserver 監聽的埠提示: 如果執行 kubectl 命令式時輸出如下錯誤資訊,則說明使用的 ~/.kube/config 檔案不對,請切換到正確的賬戶後再執行該命令: The connection to the server localhost:8080 was refused - did you specify the right host or port? 執行 kubectl get componentstatuses 命令時,apiserver 預設向 127.0.0.1 傳送請求。當 controller-manager、scheduler 以叢集模式執行時,有可能和 kube-apiserver 不在一臺機器上,這時 controller-manager 或 scheduler 的狀態為 Unhealthy,但實際上它們工作正常; 6443: 接收 https 請求的安全埠,對所有請求做認證和授權; 由於關閉了非安全埠,故沒有監聽 8080。
3.5 授權
授予 kube-apiserver 訪問 kubelet API 的許可權。 在執行 kubectl exec、run、logs 等命令時,apiserver 會將請求轉發到 kubelet 的 https 埠。本實驗定義 RBAC 規則,授權 apiserver 使用的證書(kubernetes.pem)使用者名稱(CN:kuberntes)訪問 kubelet API 的許可權:1 [root@k8smaster01 ~]# kubectl create clusterrolebinding kube-apiserver:kubelet-apis --clusterrole=system:kubelet-api-admin --user kubernetes