Kubernetes(K8S)容器集群管理环境完整部署详细教程-中篇

八、部署master节点

master节点的kube-apiserver、kube-scheduler 和 kube-controller-manager 均以多实例模式运行：kube-scheduler 和 kube-controller-manager 会自动选举产生一个 leader 实例，其它实例处于阻塞模式，当 leader 挂了后，重新选举产生新的 leader，从而保证服务可用性；kube-apiserver 是无状态的，需要通过 kube-nginx 进行代理访问，从而保证服务可用性；

下面部署命令均在k8s-master01节点上执行，然后远程分发文件和执行命令。

下载最新版本二进制文件 [root@k8s-master01 ~]# cd /opt/k8s/work [root@k8s-master01 work]# wget https://dl.k8s.io/v1.14.2/kubernetes-server-linux-amd64.tar.gz [root@k8s-master01 work]# tar -xzvf kubernetes-server-linux-amd64.tar.gz [root@k8s-master01 work]# cd kubernetes [root@k8s-master01 work]# tar -xzvf kubernetes-src.tar.gz 将二进制文件拷贝到所有 master 节点： [root@k8s-master01 ~]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp kubernetes/server/bin/{apiextensions-apiserver,cloud-controller-manager,kube-apiserver,kube-controller-manager,kube-proxy,kube-scheduler,kubeadm,kubectl,kubelet,mounter} root@${node_master_ip}:/opt/k8s/bin/ ssh root@${node_master_ip} “chmod +x /opt/k8s/bin/*” done

8.1 – 部署高可用 kube-apiserver 集群

这里部署一个三实例kube-apiserver集群环境，它们通过nginx四层代理进行访问，对外提供一个统一的vip地址，从而保证服务可用性。下面部署命令均在k8s-master01节点上执行，然后远程分发文件和执行命令。

1) 创建 kubernetes 证书和私钥 创建证书签名请求： [root@k8s-master01 ~]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# cat > kubernetes-csr.json <<EOF { “CN”: “kubernetes”, “hosts”: [ “127.0.0.1”, “172.16.60.250”, “172.16.60.241”, “172.16.60.242”, “172.16.60.243”, “${CLUSTER_KUBERNETES_SVC_IP}”, “kubernetes”, “kubernetes.default”, “kubernetes.default.svc”, “kubernetes.default.svc.cluster”, “kubernetes.default.svc.cluster.local” ], “key”: { “algo”: “rsa”, “size”: 2048 }, “names”: [ { “C”: “CN”, “ST”: “BeiJing”, “L”: “BeiJing”, “O”: “k8s”, “OU”: “4Paradigm” } ] } EOF 解释说明： • hosts 字段指定授权使用该证书的 IP 或域名列表，这里列出了 VIP 、apiserver 节点 IP、kubernetes 服务 IP 和域名； • 域名最后字符不能是 .(如不能为 kubernetes.default.svc.cluster.local.)，否则解析时失败，提示： x509: cannot parse dnsName “kubernetes.default.svc.cluster.local.”； • 如果使用非 cluster.local 域名，如 opsnull.com，则需要修改域名列表中的最后两个域名为：kubernetes.default.svc.opsnull、kubernetes.default.svc.opsnull.com • kubernetes 服务 IP 是 apiserver 自动创建的，一般是 –service-cluster-ip-range 参数指定的网段的第一个IP，后续可以通过如下命令获取： [root@k8s-master01 work]# kubectl get svc kubernetes The connection to the server 172.16.60.250:8443 was refused – did you specify the right host or port? 上面报错是因为kube-apiserver服务此时没有启动，后续待apiserver服务启动后，以上命令就可以获得了。 生成证书和私钥： [root@k8s-master01 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 kubernetes-csr.json | cfssljson -bare kubernetes [root@k8s-master01 work]# ls kubernetes*pem kubernetes-key.pem kubernetes.pem 将生成的证书和私钥文件拷贝到所有 master 节点： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” ssh root@${node_master_ip} “mkdir -p /etc/kubernetes/cert” scp kubernetes*.pem root@${node_master_ip}:/etc/kubernetes/cert/ done 2) 创建加密配置文件 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# cat > encryption-config.yaml <<EOF kind: EncryptionConfig apiVersion: v1 resources: – resources: – secrets providers: – aescbc: keys: – name: key1 secret: ${ENCRYPTION_KEY} – identity: {} EOF 将加密配置文件拷贝到 master 节点的 /etc/kubernetes 目录下： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp encryption-config.yaml root@${node_master_ip}:/etc/kubernetes/ done 3) 创建审计策略文件 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# cat > audit-policy.yaml <<EOF apiVersion: audit.k8s.io/v1beta1 kind: Policy rules: # The following requests were manually identified as high-volume and low-risk, so drop them. – level: None resources: – group: “” resources: – endpoints – services – services/status users: – system:kube-proxy verbs: – watch – level: None resources: – group: “” resources: – nodes – nodes/status userGroups: – system:nodes verbs: – get – level: None namespaces: – kube-system resources: – group: “” resources: – endpoints users: – system:kube-controller-manager – system:kube-scheduler – system:serviceaccount:kube-system:endpoint-controller verbs: – get – update – level: None resources: – group: “” resources: – namespaces – namespaces/status – namespaces/finalize users: – system:apiserver verbs: – get # Dont log HPA fetching metrics. – level: None resources: – group: metrics.k8s.io users: – system:kube-controller-manager verbs: – get – list # Dont log these read-only URLs. – level: None nonResourceURLs: – /healthz* – /version – /swagger* # Dont log events requests. – level: None resources: – group: “” resources: – events # node and pod status calls from nodes are high-volume and can be large, dont log responses for expected updates from nodes – level: Request omitStages: – RequestReceived resources: – group: “” resources: – nodes/status – pods/status users: – kubelet – system:node-problem-detector – system:serviceaccount:kube-system:node-problem-detector verbs: – update – patch – level: Request omitStages: – RequestReceived resources: – group: “” resources: – nodes/status – pods/status userGroups: – system:nodes verbs: – update – patch # deletecollection calls can be large, dont log responses for expected namespace deletions – level: Request omitStages: – RequestReceived users: – system:serviceaccount:kube-system:namespace-controller verbs: – deletecollection # Secrets, ConfigMaps, and TokenReviews can contain sensitive & binary data, # so only log at the Metadata level. – level: Metadata omitStages: – RequestReceived resources: – group: “” resources: – secrets – configmaps – group: authentication.k8s.io resources: – tokenreviews # Get repsonses can be large; skip them. – level: Request omitStages: – RequestReceived resources: – group: “” – group: admissionregistration.k8s.io – group: apiextensions.k8s.io – group: apiregistration.k8s.io – group: apps – group: authentication.k8s.io – group: authorization.k8s.io – group: autoscaling – group: batch – group: certificates.k8s.io – group: extensions – group: metrics.k8s.io – group: networking.k8s.io – group: policy – group: rbac.authorization.k8s.io – group: scheduling.k8s.io – group: settings.k8s.io – group: storage.k8s.io verbs: – get – list – watch # Default level for known APIs – level: RequestResponse omitStages: – RequestReceived resources: – group: “” – group: admissionregistration.k8s.io – group: apiextensions.k8s.io – group: apiregistration.k8s.io – group: apps – group: authentication.k8s.io – group: authorization.k8s.io – group: autoscaling – group: batch – group: certificates.k8s.io – group: extensions – group: metrics.k8s.io – group: networking.k8s.io – group: policy – group: rbac.authorization.k8s.io – group: scheduling.k8s.io – group: settings.k8s.io – group: storage.k8s.io # Default level for all other requests. – level: Metadata omitStages: – RequestReceived EOF 分发审计策略文件： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp audit-policy.yaml root@${node_master_ip}:/etc/kubernetes/audit-policy.yaml done 4) 创建后续访问 metrics-server 使用的证书 创建证书签名请求: [root@k8s-master01 work]# cat > proxy-client-csr.json <<EOF { “CN”: “aggregator”, “hosts”: [], “key”: { “algo”: “rsa”, “size”: 2048 }, “names”: [ { “C”: “CN”, “ST”: “BeiJing”, “L”: “BeiJing”, “O”: “k8s”, “OU”: “4Paradigm” } ] } EOF CN 名称为 aggregator，需要与 metrics-server 的 –requestheader-allowed-names 参数配置一致，否则访问会被 metrics-server 拒绝； 生成证书和私钥： [root@k8s-master01 work]# cfssl gencert -ca=/etc/kubernetes/cert/ca.pem -ca-key=/etc/kubernetes/cert/ca-key.pem -config=/etc/kubernetes/cert/ca-config.json -profile=kubernetes proxy-client-csr.json | cfssljson -bare proxy-client [root@k8s-master01 work]# ls proxy-client*.pem proxy-client-key.pem proxy-client.pem 将生成的证书和私钥文件拷贝到所有 master 节点： [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp proxy-client*.pem root@${node_master_ip}:/etc/kubernetes/cert/ done 5) 创建 kube-apiserver systemd unit 模板文件 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# cat > kube-apiserver.service.template <<EOF [Unit] Description=Kubernetes API Server Documentation=https://github.com/GoogleCloudPlatform/kubernetes After=network.target [Service] WorkingDirectory=${K8S_DIR}/kube-apiserver ExecStart=/opt/k8s/bin/kube-apiserver –advertise-address=##NODE_MASTER_IP## –default-not-ready-toleration-seconds=360 –default-unreachable-toleration-seconds=360 –feature-gates=DynamicAuditing=true –max-mutating-requests-inflight=2000 –max-requests-inflight=4000 –default-watch-cache-size=200 –delete-collection-workers=2 –encryption-provider-config=/etc/kubernetes/encryption-config.yaml –etcd-cafile=/etc/kubernetes/cert/ca.pem –etcd-certfile=/etc/kubernetes/cert/kubernetes.pem –etcd-keyfile=/etc/kubernetes/cert/kubernetes-key.pem –etcd-servers=${ETCD_ENDPOINTS} –bind-address=##NODE_MASTER_IP## –secure-port=6443 –tls-cert-file=/etc/kubernetes/cert/kubernetes.pem –tls-private-key-file=/etc/kubernetes/cert/kubernetes-key.pem –insecure-port=0 –audit-dynamic-configuration –audit-log-maxage=15 –audit-log-maxbackup=3 –audit-log-maxsize=100 –audit-log-mode=batch –audit-log-truncate-enabled –audit-log-batch-buffer-size=20000 –audit-log-batch-max-size=2 –audit-log-path=${K8S_DIR}/kube-apiserver/audit.log –audit-policy-file=/etc/kubernetes/audit-policy.yaml –profiling –anonymous-auth=false –client-ca-file=/etc/kubernetes/cert/ca.pem –enable-bootstrap-token-auth –requestheader-allowed-names=”” –requestheader-client-ca-file=/etc/kubernetes/cert/ca.pem –requestheader-extra-headers-prefix=”X-Remote-Extra-” –requestheader-group-headers=X-Remote-Group –requestheader-username-headers=X-Remote-User –service-account-key-file=/etc/kubernetes/cert/ca.pem –authorization-mode=Node,RBAC –runtime-config=api/all=true –enable-admission-plugins=NodeRestriction –allow-privileged=true –apiserver-count=3 –event-ttl=168h –kubelet-certificate-authority=/etc/kubernetes/cert/ca.pem –kubelet-client-certificate=/etc/kubernetes/cert/kubernetes.pem –kubelet-client-key=/etc/kubernetes/cert/kubernetes-key.pem –kubelet-https=true –kubelet-timeout=10s –proxy-client-cert-file=/etc/kubernetes/cert/proxy-client.pem –proxy-client-key-file=/etc/kubernetes/cert/proxy-client-key.pem –service-cluster-ip-range=${SERVICE_CIDR} –service-node-port-range=${NODE_PORT_RANGE} –logtostderr=true –enable-aggregator-routing=true –v=2 Restart=on-failure RestartSec=10 Type=notify LimitNOFILE=65536 [Install] WantedBy=multi-user.target EOF 解释说明： –advertise-address：apiserver 对外通告的 IP（kubernetes 服务后端节点 IP）； –default-*-toleration-seconds：设置节点异常相关的阈值； –max-*-requests-inflight：请求相关的最大阈值； –etcd-*：访问 etcd 的证书和 etcd 服务器地址； –experimental-encryption-provider-config：指定用于加密 etcd 中 secret 的配置； –bind-address： https 监听的 IP，不能为 127.0.0.1，否则外界不能访问它的安全端口 6443； –secret-port：https 监听端口； –insecure-port=0：关闭监听 http 非安全端口(8080)； –tls-*-file：指定 apiserver 使用的证书、私钥和 CA 文件； –audit-*：配置审计策略和审计日志文件相关的参数； –client-ca-file：验证 client (kue-controller-manager、kube-scheduler、kubelet、kube-proxy 等)请求所带的证书； –enable-bootstrap-token-auth：启用 kubelet bootstrap 的 token 认证； –requestheader-*：kube-apiserver 的 aggregator layer 相关的配置参数，proxy-client & HPA 需要使用； –requestheader-client-ca-file：用于签名 –proxy-client-cert-file 和 –proxy-client-key-file 指定的证书；在启用了 metric aggregator 时使用； 如果 –requestheader-allowed-names 不为空，则–proxy-client-cert-file 证书的 CN 必须位于 allowed-names 中，默认为 aggregator; –service-account-key-file：签名 ServiceAccount Token 的公钥文件，kube-controller-manager 的 –service-account-private-key-file 指定私钥文件，两者配对使用； –runtime-config=api/all=true： 启用所有版本的 APIs，如 autoscaling/v2alpha1； –authorization-mode=Node,RBAC、–anonymous-auth=false： 开启 Node 和 RBAC 授权模式，拒绝未授权的请求； –enable-admission-plugins：启用一些默认关闭的 plugins； –allow-privileged：运行执行 privileged 权限的容器； –apiserver-count=3：指定 apiserver 实例的数量； –event-ttl：指定 events 的保存时间； –kubelet-*：如果指定，则使用 https 访问 kubelet APIs；需要为证书对应的用户(上面 kubernetes*.pem 证书的用户为 kubernetes) 用户定义 RBAC 规则，否则访问 kubelet API 时提示未授权； –proxy-client-*：apiserver 访问 metrics-server 使用的证书； –service-cluster-ip-range： 指定 Service Cluster IP 地址段； –service-node-port-range： 指定 NodePort 的端口范围； 注意： 如果kube-apiserver机器没有运行 kube-proxy，则需要添加 –enable-aggregator-routing=true 参数（这里master节点没有作为node节点使用，故没有运行kube-proxy，需要加这个参数） requestheader-client-ca-file 指定的 CA 证书，必须具有 client auth and server auth！！ 为各节点创建和分发 kube-apiserver systemd unit 文件 替换模板文件中的变量，为各节点生成 systemd unit 文件： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for (( i=0; i < 3; i++ )) do sed -e “s/##NODE_MASTER_NAME##/${NODE_MASTER_NAMES[i]}/” -e “s/##NODE_MASTER_IP##/${NODE_MASTER_IPS[i]}/” kube-apiserver.service.template > kube-apiserver-${NODE_MASTER_IPS[i]}.service done 其中：NODE_NAMES 和 NODE_IPS 为相同长度的 bash 数组，分别为节点名称和对应的 IP； [root@k8s-master01 work]# ll kube-apiserver*.service -rw-r–r– 1 root root 2718 Jun 18 10:38 kube-apiserver-172.16.60.241.service -rw-r–r– 1 root root 2718 Jun 18 10:38 kube-apiserver-172.16.60.242.service -rw-r–r– 1 root root 2718 Jun 18 10:38 kube-apiserver-172.16.60.243.service 分发生成的 systemd unit 文件, 文件重命名为 kube-apiserver.service; [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp kube-apiserver-${node_master_ip}.service root@${node_master_ip}:/etc/systemd/system/kube-apiserver.service done 6) 启动 kube-apiserver 服务 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” ssh root@${node_master_ip} “mkdir -p ${K8S_DIR}/kube-apiserver” ssh root@${node_master_ip} “systemctl daemon-reload && systemctl enable kube-apiserver && systemctl restart kube-apiserver” done 注意：启动服务前必须先创建工作目录； 检查 kube-apiserver 运行状态 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” ssh root@${node_master_ip} “systemctl status kube-apiserver |grep Active:” done 预期输出： >>> 172.16.60.241 Active: active (running) since Tue 2019-06-18 10:42:42 CST; 1min 6s ago >>> 172.16.60.242 Active: active (running) since Tue 2019-06-18 10:42:47 CST; 1min 2s ago >>> 172.16.60.243 Active: active (running) since Tue 2019-06-18 10:42:51 CST; 58s ago 确保状态为 active (running)，否则查看日志，确认原因（journalctl -u kube-apiserver） 7）打印 kube-apiserver 写入 etcd 的数据 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# ETCDCTL_API=3 etcdctl –endpoints=${ETCD_ENDPOINTS} –cacert=/opt/k8s/work/ca.pem –cert=/opt/k8s/work/etcd.pem –key=/opt/k8s/work/etcd-key.pem get /registry/ –prefix –keys-only 预期会打印出很多写入到etcd中的数据信息 8）检查集群信息 [root@k8s-master01 work]# kubectl cluster-info Kubernetes master is running at https://172.16.60.250:8443 To further debug and diagnose cluster problems, use kubectl cluster-info dump. [root@k8s-master01 work]# kubectl get all –all-namespaces NAMESPACE NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE default service/kubernetes ClusterIP 10.254.0.1 <none> 443/TCP 8m25s 查看集群状态信息 [root@k8s-master01 work]# kubectl get componentstatuses #或者执行命令”kubectl get cs” NAME STATUS MESSAGE ERROR controller-manager Unhealthy Get http://127.0.0.1:10252/healthz: dial tcp 127.0.0.1:10252: connect: connection refused scheduler Unhealthy Get http://127.0.0.1:10251/healthz: dial tcp 127.0.0.1:10251: connect: connection refused etcd-0 Healthy {“health”:”true”} etcd-2 Healthy {“health”:”true”} etcd-1 Healthy {“health”:”true”} controller-managerhe 和 schedule状态为Unhealthy，是因为此时还没有部署这两个组件，待后续部署好之后再查看~ 这里注意： -> 如果执行 kubectl 命令式时输出如下错误信息，则说明使用的 ~/.kube/config 文件不对，请切换到正确的账户后再执行该命令： The connection to the server localhost:8080 was refused – did you specify the right host or port? -> 执行 kubectl get componentstatuses 命令时，apiserver 默认向 127.0.0.1 发送请求。当 controller-manager、scheduler 以集群模式运行时，有可能和kube-apiserver 不在一台机器上，这时 controller-manager 或 scheduler 的状态为 Unhealthy，但实际上它们工作正常。 9) 检查 kube-apiserver 监听的端口 [root@k8s-master01 work]# netstat -lnpt|grep kube tcp 0 0 172.16.60.241:6443 0.0.0.0:* LISTEN 15516/kube-apiserve 需要注意： 6443: 接收 https 请求的安全端口，对所有请求做认证和授权； 由于关闭了非安全端口，故没有监听 8080； 10）授予 kube-apiserver 访问 kubelet API 的权限 在执行 kubectl exec、run、logs 等命令时，apiserver 会将请求转发到 kubelet 的 https 端口。 这里定义 RBAC 规则，授权 apiserver 使用的证书（kubernetes.pem）用户名（CN：kuberntes）访问 kubelet API 的权限： [root@k8s-master01 work]# kubectl create clusterrolebinding kube-apiserver:kubelet-apis –clusterrole=system:kubelet-api-admin –user kubernetes 11）查看kube-apiserver输出的metrics 需要用到根证书 使用nginx的代理端口获取metrics [root@k8s-master01 work]# curl -s –cacert /opt/k8s/work/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.250:8443/metrics|head # HELP APIServiceOpenAPIAggregationControllerQueue1_adds (Deprecated) Total number of adds handled by workqueue: APIServiceOpenAPIAggregationControllerQueue1 # TYPE APIServiceOpenAPIAggregationControllerQueue1_adds counter APIServiceOpenAPIAggregationControllerQueue1_adds 12194 # HELP APIServiceOpenAPIAggregationControllerQueue1_depth (Deprecated) Current depth of workqueue: APIServiceOpenAPIAggregationControllerQueue1 # TYPE APIServiceOpenAPIAggregationControllerQueue1_depth gauge APIServiceOpenAPIAggregationControllerQueue1_depth 0 # HELP APIServiceOpenAPIAggregationControllerQueue1_longest_running_processor_microseconds (Deprecated) How many microseconds has the longest running processor for APIServiceOpenAPIAggregationControllerQueue1 been running. # TYPE APIServiceOpenAPIAggregationControllerQueue1_longest_running_processor_microseconds gauge APIServiceOpenAPIAggregationControllerQueue1_longest_running_processor_microseconds 0 # HELP APIServiceOpenAPIAggregationControllerQueue1_queue_latency (Deprecated) How long an item stays in workqueueAPIServiceOpenAPIAggregationControllerQueue1 before being requested. 直接使用kube-apiserver节点端口获取metrics [root@k8s-master01 work]# curl -s –cacert /opt/k8s/work/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.241:6443/metrics|head [root@k8s-master01 work]# curl -s –cacert /opt/k8s/work/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.242:6443/metrics|head [root@k8s-master01 work]# curl -s –cacert /opt/k8s/work/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.243:6443/metrics|head

8.2 – 部署高可用 kube-controller-manager 集群

该集群包含 3 个节点，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；下面部署命令均在k8s-master01节点上执行，然后远程分发文件和执行命令。

1）创建 kube-controller-manager 证书和私钥 创建证书签名请求： [root@k8s-master01 ~]# cd /opt/k8s/work [root@k8s-master01 work]# cat > kube-controller-manager-csr.json <<EOF { “CN”: “system:kube-controller-manager”, “key”: { “algo”: “rsa”, “size”: 2048 }, “hosts”: [ “127.0.0.1”, “172.16.60.241”, “172.16.60.242”, “172.16.60.243” ], “names”: [ { “C”: “CN”, “ST”: “BeiJing”, “L”: “BeiJing”, “O”: “system:kube-controller-manager”, “OU”: “4Paradigm” } ] } EOF • hosts 列表包含所有 kube-controller-manager 节点 IP； • CN 为 system:kube-controller-manager、O 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。 生成证书和私钥 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 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-controller-manager-csr.json | cfssljson -bare kube-controller-manager [root@k8s-master01 work]# ll kube-controller-manager*pem -rw——- 1 root root 1679 Jun 18 11:43 kube-controller-manager-key.pem -rw-r–r– 1 root root 1517 Jun 18 11:43 kube-controller-manager.pem 将生成的证书和私钥分发到所有 master 节点： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp kube-controller-manager*.pem root@${node_master_ip}:/etc/kubernetes/cert/ done 2) 创建和分发 kubeconfig 文件 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： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# kubectl config set-cluster kubernetes –certificate-authority=/opt/k8s/work/ca.pem –embed-certs=true –server=${KUBE_APISERVER} –kubeconfig=kube-controller-manager.kubeconfig [root@k8s-master01 work]# kubectl config set-credentials system:kube-controller-manager –client-certificate=kube-controller-manager.pem –client-key=kube-controller-manager-key.pem –embed-certs=true –kubeconfig=kube-controller-manager.kubeconfig [root@k8s-master01 work]# kubectl config set-context system:kube-controller-manager –cluster=kubernetes –user=system:kube-controller-manager –kubeconfig=kube-controller-manager.kubeconfig [root@k8s-master01 work]# kubectl config use-context system:kube-controller-manager –kubeconfig=kube-controller-manager.kubeconfig 分发 kubeconfig 到所有 master 节点： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp kube-controller-manager.kubeconfig root@${node_master_ip}:/etc/kubernetes/ done 3) 创建和分发kube-controller-manager system unit 文件 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# cat > kube-controller-manager.service.template <<EOF [Unit] Description=Kubernetes Controller Manager Documentation=https://github.com/GoogleCloudPlatform/kubernetes [Service] WorkingDirectory=${K8S_DIR}/kube-controller-manager ExecStart=/opt/k8s/bin/kube-controller-manager –profiling –cluster-name=kubernetes –controllers=*,bootstrapsigner,tokencleaner –kube-api-qps=1000 –kube-api-burst=2000 –leader-elect –use-service-account-credentials=true –concurrent-service-syncs=2 –bind-address=0.0.0.0 –tls-cert-file=/etc/kubernetes/cert/kube-controller-manager.pem –tls-private-key-file=/etc/kubernetes/cert/kube-controller-manager-key.pem –authentication-kubeconfig=/etc/kubernetes/kube-controller-manager.kubeconfig –client-ca-file=/etc/kubernetes/cert/ca.pem –requestheader-allowed-names=”” –requestheader-client-ca-file=/etc/kubernetes/cert/ca.pem –requestheader-extra-headers-prefix=”X-Remote-Extra-” –requestheader-group-headers=X-Remote-Group –requestheader-username-headers=X-Remote-User –authorization-kubeconfig=/etc/kubernetes/kube-controller-manager.kubeconfig –cluster-signing-cert-file=/etc/kubernetes/cert/ca.pem –cluster-signing-key-file=/etc/kubernetes/cert/ca-key.pem –experimental-cluster-signing-duration=8760h –horizontal-pod-autoscaler-sync-period=10s –concurrent-deployment-syncs=10 –concurrent-gc-syncs=30 –node-cidr-mask-size=24 –service-cluster-ip-range=${SERVICE_CIDR} –pod-eviction-timeout=6m –terminated-pod-gc-threshold=10000 –root-ca-file=/etc/kubernetes/cert/ca.pem –service-account-private-key-file=/etc/kubernetes/cert/ca-key.pem –kubeconfig=/etc/kubernetes/kube-controller-manager.kubeconfig –logtostderr=true –v=2 Restart=on-failure RestartSec=5 [Install] WantedBy=multi-user.target EOF 解释说明： 下面两行一般要去掉，否则执行”kubectl get cs”检查集群状态时，controller-manager状态会为”Unhealthy” –port=0：关闭监听非安全端口（http），同时 –address 参数无效，–bind-address 参数有效； –secure-port=10252 –bind-address=0.0.0.0: 在所有网络接口监听 10252 端口的 https /metrics 请求； –kubeconfig：指定 kubeconfig 文件路径，kube-controller-manager 使用它连接和验证 kube-apiserver； –authentication-kubeconfig 和 –authorization-kubeconfig：kube-controller-manager 使用它连接 apiserver，对 client 的请求进行认证和授权。kube-controller-manager 不再使用 –tls-ca-file 对请求 https metrics 的 Client 证书进行校验。如果没有配置这两个 kubeconfig 参数，则 client 连接 kube-controller-manager https 端口的请求会被拒绝(提示权限不足)。 –cluster-signing-*-file：签名 TLS Bootstrap 创建的证书； –experimental-cluster-signing-duration：指定 TLS Bootstrap 证书的有效期； –root-ca-file：放置到容器 ServiceAccount 中的 CA 证书，用来对 kube-apiserver 的证书进行校验； –service-account-private-key-file：签名 ServiceAccount 中 Token 的私钥文件，必须和 kube-apiserver 的 –service-account-key-file 指定的公钥文件配对使用； –service-cluster-ip-range ：指定 Service Cluster IP 网段，必须和 kube-apiserver 中的同名参数一致； –leader-elect=true：集群运行模式，启用选举功能；被选为 leader 的节点负责处理工作，其它节点为阻塞状态； –controllers=*,bootstrapsigner,tokencleaner：启用的控制器列表，tokencleaner 用于自动清理过期的 Bootstrap token； –horizontal-pod-autoscaler-*：custom metrics 相关参数，支持 autoscaling/v2alpha1； –tls-cert-file、–tls-private-key-file：使用 https 输出 metrics 时使用的 Server 证书和秘钥； –use-service-account-credentials=true: kube-controller-manager 中各 controller 使用 serviceaccount 访问 kube-apiserver； 为各节点创建和分发 kube-controller-mananger systemd unit 文件 替换模板文件中的变量，为各节点创建 systemd unit 文件： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for (( i=0; i < 3; i++ )) do sed -e “s/##NODE_MASTER_NAME##/${NODE_MASTER_NAMES[i]}/” -e “s/##NODE_MASTER_IP##/${NODE_MASTER_IPS[i]}/” kube-controller-manager.service.template > kube-controller-manager-${NODE_MASTER_IPS[i]}.service done 注意： NODE_NAMES 和 NODE_IPS 为相同长度的 bash 数组，分别为节点名称和对应的 IP； [root@k8s-master01 work]# ll kube-controller-manager*.service -rw-r–r– 1 root root 1878 Jun 18 12:45 kube-controller-manager-172.16.60.241.service -rw-r–r– 1 root root 1878 Jun 18 12:45 kube-controller-manager-172.16.60.242.service -rw-r–r– 1 root root 1878 Jun 18 12:45 kube-controller-manager-172.16.60.243.service 分发到所有 master 节点： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp kube-controller-manager-${node_master_ip}.service root@${node_master_ip}:/etc/systemd/system/kube-controller-manager.service done 注意：文件重命名为 kube-controller-manager.service; 启动 kube-controller-manager 服务 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” ssh root@${node_master_ip} “mkdir -p ${K8S_DIR}/kube-controller-manager” ssh root@${node_master_ip} “systemctl daemon-reload && systemctl enable kube-controller-manager && systemctl restart kube-controller-manager” done 注意：启动服务前必须先创建工作目录； 检查服务运行状态 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” ssh root@${node_master_ip} “systemctl status kube-controller-manager|grep Active” done 预期输出结果： >>> 172.16.60.241 Active: active (running) since Tue 2019-06-18 12:49:11 CST; 1min 7s ago >>> 172.16.60.242 Active: active (running) since Tue 2019-06-18 12:49:11 CST; 1min 7s ago >>> 172.16.60.243 Active: active (running) since Tue 2019-06-18 12:49:12 CST; 1min 7s ago 确保状态为 active (running)，否则查看日志，确认原因（journalctl -u kube-controller-manager） kube-controller-manager 监听 10252 端口，接收 https 请求： [root@k8s-master01 work]# netstat -lnpt|grep kube-controll tcp 0 0 172.16.60.241:10252 0.0.0.0:* LISTEN 25709/kube-controll 检查集群状态，controller-manager的状态为”ok” 注意：当kube-controller-manager集群中的1个或2个节点的controller-manager服务挂掉，只要有一个节点的controller-manager服务活着， 则集群中controller-manager的状态仍然为”ok”,仍然会继续提供服务！ [root@k8s-master01 work]# kubectl get cs NAME STATUS MESSAGE ERROR scheduler Unhealthy Get http://127.0.0.1:10251/healthz: dial tcp 127.0.0.1:10251: connect: connection refused controller-manager Healthy ok etcd-0 Healthy {“health”:”true”} etcd-1 Healthy {“health”:”true”} etcd-2 Healthy {“health”:”true”} 4) 查看输出的 metrics 注意：以下命令在3台kube-controller-manager节点上执行。 由于在kube-controller-manager启动文件中关掉了”–port=0″和”–secure-port=10252″这两个参数，则只能通过http方式获取到kube-controller-manager 输出的metrics信息。kube-controller-manager一般不会被访问，只有在监控时采集metrcis指标数据时被访问。 [root@k8s-master01 work]# curl -s http://172.16.60.241:10252/metrics|head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800″} 0 [root@k8s-master01 work]# curl -s –cacert /etc/kubernetes/cert/ca.pem http://172.16.60.241:10252/metrics |head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800″} 0 [root@k8s-master01 work]# curl -s –cacert /etc/kubernetes/cert/ca.pem http://127.0.0.1:10252/metrics |head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800″} 0 [root@k8s-master01 ~]# curl -s –cacert /opt/k8s/work/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem http://172.16.60.241:10252/metrics |head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800″} 0 5) kube-controller-manager 的权限 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： [root@k8s-master01 work]# kubectl describe clusterrole system:kube-controller-manager Name: system:kube-controller-manager Labels: kubernetes.io/bootstrapping=rbac-defaults Annotations: rbac.authorization.kubernetes.io/autoupdate: true PolicyRule: Resources Non-Resource URLs Resource Names Verbs ——— —————– ————– —– secrets [] [] [create delete get update] endpoints [] [] [create get update] serviceaccounts [] [] [create get update] events [] [] [create patch update] tokenreviews.authentication.k8s.io [] [] [create] subjectaccessreviews.authorization.k8s.io [] [] [create] configmaps [] [] [get] namespaces [] [] [get] *.* [] [] [list watch] 需要在 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。 [root@k8s-master01 work]# kubectl get clusterrole|grep controller system:controller:attachdetach-controller 141m system:controller:certificate-controller 141m system:controller:clusterrole-aggregation-controller 141m system:controller:cronjob-controller 141m system:controller:daemon-set-controller 141m system:controller:deployment-controller 141m system:controller:disruption-controller 141m system:controller:endpoint-controller 141m system:controller:expand-controller 141m system:controller:generic-garbage-collector 141m system:controller:horizontal-pod-autoscaler 141m system:controller:job-controller 141m system:controller:namespace-controller 141m system:controller:node-controller 141m system:controller:persistent-volume-binder 141m system:controller:pod-garbage-collector 141m system:controller:pv-protection-controller 141m system:controller:pvc-protection-controller 141m system:controller:replicaset-controller 141m system:controller:replication-controller 141m system:controller:resourcequota-controller 141m system:controller:route-controller 141m system:controller:service-account-controller 141m system:controller:service-controller 141m system:controller:statefulset-controller 141m system:controller:ttl-controller 141m system:kube-controller-manager 141m 以 deployment controller 为例： [root@k8s-master01 work]# kubectl describe clusterrole system:controller:deployment-controller Name: system:controller:deployment-controller Labels: kubernetes.io/bootstrapping=rbac-defaults Annotations: rbac.authorization.kubernetes.io/autoupdate: true PolicyRule: Resources Non-Resource URLs Resource Names Verbs ——— —————– ————– —– replicasets.apps [] [] [create delete get list patch update watch] replicasets.extensions [] [] [create delete get list patch update watch] events [] [] [create patch update] pods [] [] [get list update watch] deployments.apps [] [] [get list update watch] deployments.extensions [] [] [get list update watch] deployments.apps/finalizers [] [] [update] deployments.apps/status [] [] [update] deployments.extensions/finalizers [] [] [update] deployments.extensions/status [] [] [update] 6）查看kube-controller-manager集群中当前的leader [root@k8s-master01 work]# kubectl get endpoints kube-controller-manager –namespace=kube-system -o yaml apiVersion: v1 kind: Endpoints metadata: annotations: control-plane.alpha.kubernetes.io/leader: {“holderIdentity”:”k8s-master02_4e449819-9185-11e9-82b6-005056ac42a4″,”leaseDurationSeconds”:15,”acquireTime”:”2019-06-18T04:55:49Z”,”renewTime”:”2019-06-18T05:04:54Z”,”leaderTransitions”:3} creationTimestamp: “2019-06-18T04:03:07Z” name: kube-controller-manager namespace: kube-system resourceVersion: “4604” selfLink: /api/v1/namespaces/kube-system/endpoints/kube-controller-manager uid: fa824018-917d-11e9-90d4-005056ac7c81 可见，当前的leader为k8s-master02节点。 测试 kube-controller-manager 集群的高可用 停掉一个或两个节点的 kube-controller-manager 服务，观察其它节点的日志，看是否获取了 leader 权限。 比如停掉k8s-master02节点的kube-controller-manager 服务 [root@k8s-master02 ~]# systemctl stop kube-controller-manager [root@k8s-master02 ~]# ps -ef|grep kube-controller-manager root 25677 11006 0 13:06 pts/0 00:00:00 grep –color=auto kube-controller-manager 接着观察kube-controller-manager集群当前的leader情况 [root@k8s-master01 work]# kubectl get endpoints kube-controller-manager –namespace=kube-system -o yaml apiVersion: v1 kind: Endpoints metadata: annotations: control-plane.alpha.kubernetes.io/leader: {“holderIdentity”:”k8s-master03_4e4c28b5-9185-11e9-b98a-005056ac7136″,”leaseDurationSeconds”:15,”acquireTime”:”2019-06-18T05:06:32Z”,”renewTime”:”2019-06-18T05:06:57Z”,”leaderTransitions”:4} creationTimestamp: “2019-06-18T04:03:07Z” name: kube-controller-manager namespace: kube-system resourceVersion: “4695” selfLink: /api/v1/namespaces/kube-system/endpoints/kube-controller-manager uid: fa824018-917d-11e9-90d4-005056ac7c81 发现当前leader已经转移到k8s-master03节点上了！！

8.3 – 部署高可用 kube-scheduler 集群

该集群包含 3 个节点，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 节点不可用后，剩余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-scheduler 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，10251) 输出 prometheus 格式的 metrics；

下面部署命令均在k8s-master01节点上执行，然后远程分发文件和执行命令。

1）创建 kube-scheduler 证书和私钥 创建证书签名请求： [root@k8s-master01 ~]# cd /opt/k8s/work [root@k8s-master01 work]# cat > kube-scheduler-csr.json <<EOF { “CN”: “system:kube-scheduler”, “hosts”: [ “127.0.0.1”, “172.16.60.241”, “172.16.60.242”, “172.16.60.243” ], “key”: { “algo”: “rsa”, “size”: 2048 }, “names”: [ { “C”: “CN”, “ST”: “BeiJing”, “L”: “BeiJing”, “O”: “system:kube-scheduler”, “OU”: “4Paradigm” } ] } EOF 解释说明： hosts 列表包含所有 kube-scheduler 节点 IP； CN 和 O 均为 system:kube-scheduler，kubernetes 内置的 ClusterRoleBindings system:kube-scheduler 将赋予 kube-scheduler 工作所需的权限； 生成证书和私钥： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 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-scheduler-csr.json | cfssljson -bare kube-scheduler [root@k8s-master01 work]# ls kube-scheduler*pem kube-scheduler-key.pem kube-scheduler.pem 将生成的证书和私钥分发到所有 master 节点： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp kube-scheduler*.pem root@${node_master_ip}:/etc/kubernetes/cert/ done 2) 创建和分发 kubeconfig 文件 kube-scheduler 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-scheduler 证书： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# kubectl config set-cluster kubernetes –certificate-authority=/opt/k8s/work/ca.pem –embed-certs=true –server=${KUBE_APISERVER} –kubeconfig=kube-scheduler.kubeconfig [root@k8s-master01 work]# kubectl config set-credentials system:kube-scheduler –client-certificate=kube-scheduler.pem –client-key=kube-scheduler-key.pem –embed-certs=true –kubeconfig=kube-scheduler.kubeconfig [root@k8s-master01 work]# kubectl config set-context system:kube-scheduler –cluster=kubernetes –user=system:kube-scheduler –kubeconfig=kube-scheduler.kubeconfig [root@k8s-master01 work]# kubectl config use-context system:kube-scheduler –kubeconfig=kube-scheduler.kubeconfig 分发 kubeconfig 到所有 master 节点： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp kube-scheduler.kubeconfig root@${node_master_ip}:/etc/kubernetes/ done 3) 创建 kube-scheduler 配置文件 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# cat >kube-scheduler.yaml.template <<EOF apiVersion: kubescheduler.config.k8s.io/v1alpha1 kind: KubeSchedulerConfiguration bindTimeoutSeconds: 600 clientConnection: burst: 200 kubeconfig: “/etc/kubernetes/kube-scheduler.kubeconfig” qps: 100 enableContentionProfiling: false enableProfiling: true hardPodAffinitySymmetricWeight: 1 healthzBindAddress: 0.0.0.0:10251 leaderElection: leaderElect: true metricsBindAddress: 0.0.0.0:10251 EOF 注意：这里的ip地址最好用0.0.0.0，不然执行”kubectl get cs”查看schedule的集群状态会是”Unhealthy” –kubeconfig：指定 kubeconfig 文件路径，kube-scheduler 使用它连接和验证 kube-apiserver； –leader-elect=true：集群运行模式，启用选举功能；被选为 leader 的节点负责处理工作，其它节点为阻塞状态； 替换模板文件中的变量： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for (( i=0; i < 3; i++ )) do sed -e “s/##NODE_MASTER_NAME##/${NODE_MASTER_NAMES[i]}/” -e “s/##NODE_MASTER_IP##/${NODE_MASTER_IPS[i]}/” kube-scheduler.yaml.template > kube-scheduler-${NODE_MASTER_IPS[i]}.yaml done 注意：NODE_NAMES 和 NODE_IPS 为相同长度的 bash 数组，分别为节点名称和对应的 IP； [root@k8s-master01 work]# ll kube-scheduler*.yaml -rw-r–r– 1 root root 399 Jun 18 14:57 kube-scheduler-172.16.60.241.yaml -rw-r–r– 1 root root 399 Jun 18 14:57 kube-scheduler-172.16.60.242.yaml -rw-r–r– 1 root root 399 Jun 18 14:57 kube-scheduler-172.16.60.243.yaml 分发 kube-scheduler 配置文件到所有 master 节点： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp kube-scheduler-${node_master_ip}.yaml root@${node_master_ip}:/etc/kubernetes/kube-scheduler.yaml done 注意：重命名为 kube-scheduler.yaml; 4）创建 kube-scheduler systemd unit 模板文件 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# cat > kube-scheduler.service.template <<EOF [Unit] Description=Kubernetes Scheduler Documentation=https://github.com/GoogleCloudPlatform/kubernetes [Service] WorkingDirectory=${K8S_DIR}/kube-scheduler ExecStart=/opt/k8s/bin/kube-scheduler –config=/etc/kubernetes/kube-scheduler.yaml –bind-address=0.0.0.0 –tls-cert-file=/etc/kubernetes/cert/kube-scheduler.pem –tls-private-key-file=/etc/kubernetes/cert/kube-scheduler-key.pem –authentication-kubeconfig=/etc/kubernetes/kube-scheduler.kubeconfig –client-ca-file=/etc/kubernetes/cert/ca.pem –requestheader-allowed-names=”” –requestheader-client-ca-file=/etc/kubernetes/cert/ca.pem –requestheader-extra-headers-prefix=”X-Remote-Extra-” –requestheader-group-headers=X-Remote-Group –requestheader-username-headers=X-Remote-User –authorization-kubeconfig=/etc/kubernetes/kube-scheduler.kubeconfig –logtostderr=true –v=2 Restart=always RestartSec=5 StartLimitInterval=0 [Install] WantedBy=multi-user.target EOF 为各节点创建和分发 kube-scheduler systemd unit 文件 替换模板文件中的变量，为各节点创建 systemd unit 文件： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for (( i=0; i < 3; i++ )) do sed -e “s/##NODE_MASTER_NAME##/${NODE_MASTER_NAMES[i]}/” -e “s/##NODE_MASTER_IP##/${NODE_MASTER_IPS[i]}/” kube-scheduler.service.template > kube-scheduler-${NODE_MASTER_IPS[i]}.service done 其中：NODE_NAMES 和 NODE_IPS 为相同长度的 bash 数组，分别为节点名称和对应的 IP； [root@k8s-master01 work]# ll kube-scheduler*.service -rw-r–r– 1 root root 981 Jun 18 15:30 kube-scheduler-172.16.60.241.service -rw-r–r– 1 root root 981 Jun 18 15:30 kube-scheduler-172.16.60.242.service -rw-r–r– 1 root root 981 Jun 18 15:30 kube-scheduler-172.16.60.243.service 分发 systemd unit 文件到所有 master 节点： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” scp kube-scheduler-${node_master_ip}.service root@${node_master_ip}:/etc/systemd/system/kube-scheduler.service done 5) 启动 kube-scheduler 服务 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” ssh root@${node_master_ip} “mkdir -p ${K8S_DIR}/kube-scheduler” ssh root@${node_master_ip} “systemctl daemon-reload && systemctl enable kube-scheduler && systemctl restart kube-scheduler” done 注意：启动服务前必须先创建工作目录； 检查服务运行状态 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_master_ip in ${NODE_MASTER_IPS[@]} do echo “>>> ${node_master_ip}” ssh root@${node_master_ip} “systemctl status kube-scheduler|grep Active” done 预期输出结果: >>> 172.16.60.241 Active: active (running) since Tue 2019-06-18 15:33:29 CST; 1min 12s ago >>> 172.16.60.242 Active: active (running) since Tue 2019-06-18 15:33:30 CST; 1min 11s ago >>> 172.16.60.243 Active: active (running) since Tue 2019-06-18 15:33:30 CST; 1min 11s ago 确保状态为 active (running)，否则查看日志，确认原因: (journalctl -u kube-scheduler) 看看集群状态，此时状态均为”ok” [root@k8s-master01 work]# kubectl get cs NAME STATUS MESSAGE ERROR scheduler Healthy ok controller-manager Healthy ok etcd-2 Healthy {“health”:”true”} etcd-0 Healthy {“health”:”true”} etcd-1 Healthy {“health”:”true”} 6) 查看输出的 metrics 注意：以下命令要在kube-scheduler集群节点上执行。 kube-scheduler监听10251和10259端口： 10251：接收 http 请求，非安全端口，不需要认证授权； 10259：接收 https 请求，安全端口，需要认证授权； 两个接口都对外提供 /metrics 和 /healthz 的访问。 [root@k8s-master01 work]# netstat -lnpt |grep kube-schedule tcp6 0 0 :::10251 :::* LISTEN 6075/kube-scheduler tcp6 0 0 :::10259 :::* LISTEN 6075/kube-scheduler [root@k8s-master01 work]# lsof -i:10251 COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME kube-sche 6075 root 3u IPv6 628571 0t0 TCP *:10251 (LISTEN) [root@k8s-master01 work]# lsof -i:10259 COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME kube-sche 6075 root 5u IPv6 628574 0t0 TCP *:10259 (LISTEN) 下面几种方式均能获取到kube-schedule的metrics数据信息（分别使用http的10251 和 https的10259端口） [root@k8s-master01 work]# curl -s http://172.16.60.241:10251/metrics |head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800″} 0 [root@k8s-master01 work]# curl -s http://127.0.0.1:10251/metrics |head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800″} 0 [root@k8s-master01 work]# curl -s –cacert /etc/kubernetes/cert/ca.pem http://172.16.60.241:10251/metrics |head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800″} 0 [root@k8s-master01 work]# curl -s –cacert /etc/kubernetes/cert/ca.pem http://127.0.0.1:10251/metrics |head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800″} 0 [root@k8s-master01 work]# curl -s –cacert /opt/k8s/work/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.241:10259/metrics |head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800″} 0 7）查看当前的 leader [root@k8s-master01 work]# kubectl get endpoints kube-scheduler –namespace=kube-system -o yaml apiVersion: v1 kind: Endpoints metadata: annotations: control-plane.alpha.kubernetes.io/leader: {“holderIdentity”:”k8s-master01_5eac29d7-919b-11e9-b242-005056ac7c81″,”leaseDurationSeconds”:15,”acquireTime”:”2019-06-18T07:33:31Z”,”renewTime”:”2019-06-18T07:41:13Z”,”leaderTransitions”:0} creationTimestamp: “2019-06-18T07:33:31Z” name: kube-scheduler namespace: kube-system resourceVersion: “12218” selfLink: /api/v1/namespaces/kube-system/endpoints/kube-scheduler uid: 5f466875-919b-11e9-90d4-005056ac7c81 可见，当前的 leader 为 k8s-master01 节点。 测试 kube-scheduler 集群的高可用 随便找一个或两个 master 节点，停掉 kube-scheduler 服务，看其它节点是否获取了 leader 权限。 比如停掉k8s-master01节点的kube-schedule服务，查看下leader的转移情况 [root@k8s-master01 work]# systemctl stop kube-scheduler [root@k8s-master01 work]# ps -ef|grep kube-scheduler root 6871 2379 0 15:42 pts/2 00:00:00 grep –color=auto kube-scheduler 再次看看当前的leader，发现leader已经转移为k8s-master02节点了 [root@k8s-master01 work]# kubectl get endpoints kube-scheduler –namespace=kube-system -o yaml apiVersion: v1 kind: Endpoints metadata: annotations: control-plane.alpha.kubernetes.io/leader: {“holderIdentity”:”k8s-master02_5efade79-919b-11e9-bbe2-005056ac42a4″,”leaseDurationSeconds”:15,”acquireTime”:”2019-06-18T07:43:03Z”,”renewTime”:”2019-06-18T07:43:12Z”,”leaderTransitions”:1} creationTimestamp: “2019-06-18T07:33:31Z” name: kube-scheduler namespace: kube-system resourceVersion: “12363” selfLink: /api/v1/namespaces/kube-system/endpoints/kube-scheduler uid: 5f466875-919b-11e9-90d4-005056ac7c81

九、部署node工作节点

kubernetes node节点运行的组件有docker、kubelet、kube-proxy、flanneld。

下面部署命令均在k8s-master01节点上执行，然后远程分发文件和执行命令。

安装依赖包 [root@k8s-master01 ~]# source /opt/k8s/bin/environment.sh [root@k8s-master01 ~]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh root@${node_node_ip} “yum install -y epel-release” ssh root@${node_node_ip} “yum install -y conntrack ipvsadm ntp ntpdate ipset jq iptables curl sysstat libseccomp && modprobe ip_vs ” done

9.1 – 部署 docker 组件

docker 运行和管理容器，kubelet 通过 Container Runtime Interface (CRI) 与它进行交互。

下面操作均在k8s-master01上执行，然后远程分发文件和执行命令。

1) 下载和分发 docker 二进制文件 [root@k8s-master01 ~]# cd /opt/k8s/work [root@k8s-master01 work]# wget https://download.docker.com/linux/static/stable/x86_64/docker-18.09.6.tgz [root@k8s-master01 work]# tar -xvf docker-18.09.6.tgz 分发二进制文件到所有node节点： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” scp docker/* root@${node_node_ip}:/opt/k8s/bin/ ssh root@${node_node_ip} “chmod +x /opt/k8s/bin/*” done 2) 创建和分发 systemd unit 文件 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# cat > docker.service <<“EOF” [Unit] Description=Docker Application Container Engine Documentation=http://docs.docker.io [Service] WorkingDirectory=##DOCKER_DIR## Environment=”PATH=/opt/k8s/bin:/bin:/sbin:/usr/bin:/usr/sbin” EnvironmentFile=-/run/flannel/docker ExecStart=/opt/k8s/bin/dockerd $DOCKER_NETWORK_OPTIONS ExecReload=/bin/kill -s HUP $MAINPID Restart=on-failure RestartSec=5 LimitNOFILE=infinity LimitNPROC=infinity LimitCORE=infinity Delegate=yes KillMode=process [Install] WantedBy=multi-user.target EOF 注意事项： -> EOF 前后有双引号，这样 bash 不会替换文档中的变量，如 $DOCKER_NETWORK_OPTIONS (这些环境变量是 systemd 负责替换的。)； -> dockerd 运行时会调用其它 docker 命令，如 docker-proxy，所以需要将 docker 命令所在的目录加到 PATH 环境变量中； -> flanneld 启动时将网络配置写入 /run/flannel/docker 文件中，dockerd 启动前读取该文件中的环境变量 DOCKER_NETWORK_OPTIONS ，然后设置 docker0 网桥网段； -> 如果指定了多个 EnvironmentFile 选项，则必须将 /run/flannel/docker 放在最后(确保 docker0 使用 flanneld 生成的 bip 参数)； -> docker 需要以 root 用于运行； -> docker 从 1.13 版本开始，可能将 iptables FORWARD chain的默认策略设置为DROP，从而导致 ping 其它 Node 上的 Pod IP 失败，遇到这种情况时，需要手动设置策略为 ACCEPT： # iptables -P FORWARD ACCEPT 并且把以下命令写入 /etc/rc.local 文件中，防止节点重启iptables FORWARD chain的默认策略又还原为DROP # /sbin/iptables -P FORWARD ACCEPT 分发 systemd unit 文件到所有node节点机器: [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# sed -i -e “s|##DOCKER_DIR##|${DOCKER_DIR}|” docker.service [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” scp docker.service root@${node_node_ip}:/etc/systemd/system/ done 3) 配置和分发 docker 配置文件 使用国内的仓库镜像服务器以加快 pull image 的速度，同时增加下载的并发数 (需要重启 dockerd 生效)： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# cat > docker-daemon.json <<EOF { “registry-mirrors”: [“https://docker.mirrors.ustc.edu.cn”,”https://hub-mirror.c.163.com”], “insecure-registries”: [“docker02:35000”], “max-concurrent-downloads”: 20, “live-restore”: true, “max-concurrent-uploads”: 10, “debug”: true, “data-root”: “${DOCKER_DIR}/data”, “exec-root”: “${DOCKER_DIR}/exec”, “log-opts”: { “max-size”: “100m”, “max-file”: “5” } } EOF 分发 docker 配置文件到所有 node 节点： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh root@${node_node_ip} “mkdir -p /etc/docker/ ${DOCKER_DIR}/{data,exec}” scp docker-daemon.json root@${node_node_ip}:/etc/docker/daemon.json done 4) 启动 docker 服务 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh root@${node_node_ip} “systemctl daemon-reload && systemctl enable docker && systemctl restart docker” done 检查服务运行状态 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh root@${node_node_ip} “systemctl status docker|grep Active” done 预期输出结果： >>> 172.16.60.244 Active: active (running) since Tue 2019-06-18 16:28:32 CST; 42s ago >>> 172.16.60.245 Active: active (running) since Tue 2019-06-18 16:28:31 CST; 42s ago >>> 172.16.60.246 Active: active (running) since Tue 2019-06-18 16:28:32 CST; 42s ago 确保状态为 active (running)，否则查看日志，确认原因 (journalctl -u docker) 5) 检查 docker0 网桥 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh root@${node_node_ip} “/usr/sbin/ip addr show flannel.1 && /usr/sbin/ip addr show docker0” done 预期输出结果： >>> 172.16.60.244 3: flannel.1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UNKNOWN group default link/ether c6:c2:d1:5a:9a:8a brd ff:ff:ff:ff:ff:ff inet 172.30.88.0/32 scope global flannel.1 valid_lft forever preferred_lft forever 4: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default link/ether 02:42:27:3c:5e:5f brd ff:ff:ff:ff:ff:ff inet 172.30.88.1/21 brd 172.30.95.255 scope global docker0 valid_lft forever preferred_lft forever >>> 172.16.60.245 3: flannel.1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UNKNOWN group default link/ether 02:36:1d:ab:c4:86 brd ff:ff:ff:ff:ff:ff inet 172.30.56.0/32 scope global flannel.1 valid_lft forever preferred_lft forever 4: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default link/ether 02:42:6f:36:7d:fb brd ff:ff:ff:ff:ff:ff inet 172.30.56.1/21 brd 172.30.63.255 scope global docker0 valid_lft forever preferred_lft forever >>> 172.16.60.246 3: flannel.1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UNKNOWN group default link/ether 4e:73:d1:0e:27:c0 brd ff:ff:ff:ff:ff:ff inet 172.30.72.0/32 scope global flannel.1 valid_lft forever preferred_lft forever 4: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default link/ether 02:42:21:39:f4:9e brd ff:ff:ff:ff:ff:ff inet 172.30.72.1/21 brd 172.30.79.255 scope global docker0 valid_lft forever preferred_lft forever 确认各node节点的docker0网桥和flannel.1接口的IP一定要处于同一个网段中(如下 172.30.88.0/32 位于 172.30.88.1/21 中)！！！ 到任意一个node节点上查看 docker 的状态信息 [root@k8s-node01 ~]# ps -elfH|grep docker 0 S root 21573 18744 0 80 0 – 28180 pipe_w 16:32 pts/2 00:00:00 grep –color=auto docker 4 S root 21147 1 0 80 0 – 173769 futex_ 16:28 ? 00:00:00 /opt/k8s/bin/dockerd –bip=172.30.88.1/21 –ip-masq=false –mtu=1450 4 S root 21175 21147 0 80 0 – 120415 futex_ 16:28 ? 00:00:00 containerd –config /data/k8s/docker/exec/containerd/containerd.toml –log-level debug [root@k8s-node01 ~]# docker info Containers: 0 Running: 0 Paused: 0 Stopped: 0 Images: 0 Server Version: 18.09.6 Storage Driver: overlay2 Backing Filesystem: xfs Supports d_type: true Native Overlay Diff: true Logging Driver: json-file Cgroup Driver: cgroupfs Plugins: Volume: local Network: bridge host macvlan null overlay Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog Swarm: inactive Runtimes: runc Default Runtime: runc Init Binary: docker-init containerd version: bb71b10fd8f58240ca47fbb579b9d1028eea7c84 runc version: 2b18fe1d885ee5083ef9f0838fee39b62d653e30 init version: fec3683 Security Options: seccomp Profile: default Kernel Version: 4.4.181-1.el7.elrepo.x86_64 Operating System: CentOS Linux 7 (Core) OSType: linux Architecture: x86_64 CPUs: 4 Total Memory: 3.859GiB Name: k8s-node01 ID: R24D:75E5:2OWS:SNU5:NPSE:SBKH:WKLZ:2ZH7:6ITY:3BE2:YHRG:6WRU Docker Root Dir: /data/k8s/docker/data Debug Mode (client): false Debug Mode (server): true File Descriptors: 22 Goroutines: 43 System Time: 2019-06-18T16:32:44.260301822+08:00 EventsListeners: 0 Registry: https://index.docker.io/v1/ Labels: Experimental: false Insecure Registries: docker02:35000 127.0.0.0/8 Registry Mirrors: https://docker.mirrors.ustc.edu.cn/ https://hub-mirror.c.163.com/ Live Restore Enabled: true Product License: Community Engine

9.2 – 部署 kubelet 组件

kubelet 运行在每个node节点上，接收 kube-apiserver 发送的请求，管理 Pod 容器，执行交互式命令，如 exec、run、logs 等。kubelet 启动时自动向 kube-apiserver 注册节点信息，内置的 cadvisor 统计和监控节点的资源使用情况。为确保安全，部署时关闭了 kubelet 的非安全 http 端口，对请求进行认证和授权，拒绝未授权的访问(如 apiserver、heapster 的请求)。

下面部署命令均在k8s-master01节点上执行，然后远程分发文件和执行命令。

1）下载和分发 kubelet 二进制文件 [root@k8s-master01 ~]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” scp kubernetes/server/bin/kubelet root@${node_node_ip}:/opt/k8s/bin/ ssh root@${node_node_ip} “chmod +x /opt/k8s/bin/*” done 2）创建 kubelet bootstrap kubeconfig 文件 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_name in ${NODE_NODE_NAMES[@]} do echo “>>> ${node_node_name}” # 创建 token export BOOTSTRAP_TOKEN=$(kubeadm token create –description kubelet-bootstrap-token –groups system:bootstrappers:${node_node_name} –kubeconfig ~/.kube/config) # 设置集群参数 kubectl config set-cluster kubernetes –certificate-authority=/etc/kubernetes/cert/ca.pem –embed-certs=true –server=${KUBE_APISERVER} –kubeconfig=kubelet-bootstrap-${node_node_name}.kubeconfig # 设置客户端认证参数 kubectl config set-credentials kubelet-bootstrap –token=${BOOTSTRAP_TOKEN} –kubeconfig=kubelet-bootstrap-${node_node_name}.kubeconfig # 设置上下文参数 kubectl config set-context default –cluster=kubernetes –user=kubelet-bootstrap –kubeconfig=kubelet-bootstrap-${node_node_name}.kubeconfig # 设置默认上下文 kubectl config use-context default –kubeconfig=kubelet-bootstrap-${node_node_name}.kubeconfig done 解释说明: 向 kubeconfig 写入的是 token，bootstrap 结束后 kube-controller-manager 为 kubelet 创建 client 和 server 证书； 查看 kubeadm 为各节点创建的 token： [root@k8s-master01 work]# kubeadm token list –kubeconfig ~/.kube/config TOKEN TTL EXPIRES USAGES DESCRIPTION EXTRA GROUPS 0zqowl.aye8f834jtq9vm9t 23h 2019-06-19T16:50:43+08:00 authentication,signing kubelet-bootstrap-token system:bootstrappers:k8s-node03 b46tq2.muab337gxwl0dsqn 23h 2019-06-19T16:50:43+08:00 authentication,signing kubelet-bootstrap-token system:bootstrappers:k8s-node02 heh41x.foguhh1qa5crpzlq 23h 2019-06-19T16:50:42+08:00 authentication,signing kubelet-bootstrap-token system:bootstrappers:k8s-node01 解释说明： -> token 有效期为 1 天，超期后将不能再被用来 boostrap kubelet，且会被 kube-controller-manager 的 tokencleaner 清理； -> kube-apiserver 接收 kubelet 的 bootstrap token 后，将请求的 user 设置为 system:bootstrap:<Token ID>，group 设置为 system:bootstrappers， 后续将为这个 group 设置 ClusterRoleBinding； 查看各 token 关联的 Secret： [root@k8s-master01 work]# kubectl get secrets -n kube-system|grep bootstrap-token bootstrap-token-0zqowl bootstrap.kubernetes.io/token 7 88s bootstrap-token-b46tq2 bootstrap.kubernetes.io/token 7 88s bootstrap-token-heh41x bootstrap.kubernetes.io/token 7 89s 3) 分发 bootstrap kubeconfig 文件到所有node节点 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_name in ${NODE_NODE_NAMES[@]} do echo “>>> ${node_node_name}” scp kubelet-bootstrap-${node_node_name}.kubeconfig root@${node_node_name}:/etc/kubernetes/kubelet-bootstrap.kubeconfig done 4) 创建和分发 kubelet 参数配置文件 从 v1.10 开始，部分 kubelet 参数需在配置文件中配置，kubelet –help 会提示： DEPRECATED: This parameter should be set via the config file specified by the Kubelets –config flag 创建 kubelet 参数配置文件模板： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# cat > kubelet-config.yaml.template <<EOF kind: KubeletConfiguration apiVersion: kubelet.config.k8s.io/v1beta1 address: “##NODE_NODE_IP##” staticPodPath: “” syncFrequency: 1m fileCheckFrequency: 20s httpCheckFrequency: 20s staticPodURL: “” port: 10250 readOnlyPort: 0 rotateCertificates: true serverTLSBootstrap: true authentication: anonymous: enabled: false webhook: enabled: true x509: clientCAFile: “/etc/kubernetes/cert/ca.pem” authorization: mode: Webhook registryPullQPS: 0 registryBurst: 20 eventRecordQPS: 0 eventBurst: 20 enableDebuggingHandlers: true enableContentionProfiling: true healthzPort: 10248 healthzBindAddress: “##NODE_NODE_IP##” clusterDomain: “${CLUSTER_DNS_DOMAIN}” clusterDNS: – “${CLUSTER_DNS_SVC_IP}” nodeStatusUpdateFrequency: 10s nodeStatusReportFrequency: 1m imageMinimumGCAge: 2m imageGCHighThresholdPercent: 85 imageGCLowThresholdPercent: 80 volumeStatsAggPeriod: 1m kubeletCgroups: “” systemCgroups: “” cgroupRoot: “” cgroupsPerQOS: true cgroupDriver: cgroupfs runtimeRequestTimeout: 10m hairpinMode: promiscuous-bridge maxPods: 220 podCIDR: “${CLUSTER_CIDR}” podPidsLimit: -1 resolvConf: /etc/resolv.conf maxOpenFiles: 1000000 kubeAPIQPS: 1000 kubeAPIBurst: 2000 serializeImagePulls: false evictionHard: memory.available: “100Mi” nodefs.available: “10%” nodefs.inodesFree: “5%” imagefs.available: “15%” evictionSoft: {} enableControllerAttachDetach: true failSwapOn: true containerLogMaxSize: 20Mi containerLogMaxFiles: 10 systemReserved: {} kubeReserved: {} systemReservedCgroup: “” kubeReservedCgroup: “” enforceNodeAllocatable: [“pods”] EOF 解释说明: -> address：kubelet 安全端口（https，10250）监听的地址，不能为 127.0.0.1，否则 kube-apiserver、heapster 等不能调用 kubelet 的 API； -> readOnlyPort=0：关闭只读端口(默认 10255)，等效为未指定； -> authentication.anonymous.enabled：设置为 false，不允许匿名�访问 10250 端口； -> authentication.x509.clientCAFile：指定签名客户端证书的 CA 证书，开启 HTTP 证书认证； -> authentication.webhook.enabled=true：开启 HTTPs bearer token 认证； -> 对于未通过 x509 证书和 webhook 认证的请求(kube-apiserver 或其他客户端)，将被拒绝，提示 Unauthorized； -> authroization.mode=Webhook：kubelet 使用 SubjectAccessReview API 查询 kube-apiserver 某 user、group 是否具有操作资源的权限(RBAC)； -> featureGates.RotateKubeletClientCertificate、featureGates.RotateKubeletServerCertificate：自动 rotate 证书，证书的有效期取决于 kube-controller-manager 的 –experimental-cluster-signing-duration 参数； -> 需要 root 账户运行； 为各节点创建和分发 kubelet 配置文件： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” sed -e “s/##NODE_NODE_IP##/${node_node_ip}/” kubelet-config.yaml.template > kubelet-config-${node_node_ip}.yaml.template scp kubelet-config-${node_node_ip}.yaml.template root@${node_node_ip}:/etc/kubernetes/kubelet-config.yaml done 5）创建和分发 kubelet systemd unit 文件 创建 kubelet systemd unit 文件模板： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# cat > kubelet.service.template <<EOF [Unit] Description=Kubernetes Kubelet Documentation=https://github.com/GoogleCloudPlatform/kubernetes After=docker.service Requires=docker.service [Service] WorkingDirectory=${K8S_DIR}/kubelet ExecStart=/opt/k8s/bin/kubelet –allow-privileged=true –bootstrap-kubeconfig=/etc/kubernetes/kubelet-bootstrap.kubeconfig –cert-dir=/etc/kubernetes/cert –cni-conf-dir=/etc/cni/net.d –container-runtime=docker –container-runtime-endpoint=unix:///var/run/dockershim.sock –root-dir=${K8S_DIR}/kubelet –kubeconfig=/etc/kubernetes/kubelet.kubeconfig –config=/etc/kubernetes/kubelet-config.yaml –hostname-override=##NODE_NODE_NAME## –pod-infra-container-image=registry.cn-beijing.aliyuncs.com/k8s_images/pause-amd64:3.1 –image-pull-progress-deadline=15m –volume-plugin-dir=${K8S_DIR}/kubelet/kubelet-plugins/volume/exec/ –logtostderr=true –v=2 Restart=always RestartSec=5 StartLimitInterval=0 [Install] WantedBy=multi-user.target EOF 解释说明： -> 如果设置了 –hostname-override 选项，则 kube-proxy 也需要设置该选项，否则会出现找不到 Node 的情况； -> –bootstrap-kubeconfig：指向 bootstrap kubeconfig 文件，kubelet 使用该文件中的用户名和 token 向 kube-apiserver 发送 TLS Bootstrapping 请求； -> K8S approve kubelet 的 csr 请求后，在 –cert-dir 目录创建证书和私钥文件，然后写入 –kubeconfig 文件； -> –pod-infra-container-image 不使用 redhat 的 pod-infrastructure:latest 镜像，它不能回收容器的僵尸； 为各节点创建和分发 kubelet systemd unit 文件： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_name in ${NODE_NODE_NAMES[@]} do echo “>>> ${node_node_name}” sed -e “s/##NODE_NODE_NAME##/${node_node_name}/” kubelet.service.template > kubelet-${node_node_name}.service scp kubelet-${node_node_name}.service root@${node_node_name}:/etc/systemd/system/kubelet.service done 6）Bootstrap Token Auth 和授予权限 -> kubelet启动时查找–kubeletconfig参数对应的文件是否存在，如果不存在则使用 –bootstrap-kubeconfig 指定的 kubeconfig 文件向 kube-apiserver 发送证书签名请求 (CSR)。 -> kube-apiserver 收到 CSR 请求后，对其中的 Token 进行认证，认证通过后将请求的 user 设置为 system:bootstrap:<Token ID>，group 设置为 system:bootstrappers， 这一过程称为 Bootstrap Token Auth。 -> 默认情况下，这个 user 和 group 没有创建 CSR 的权限，kubelet 启动失败，错误日志如下： # journalctl -u kubelet -a |grep -A 2 certificatesigningrequests May 9 22:48:41 k8s-master01 kubelet[128468]: I0526 22:48:41.798230 128468 certificate_manager.go:366] Rotating certificates May 9 22:48:41 k8s-master01 kubelet[128468]: E0526 22:48:41.801997 128468 certificate_manager.go:385] Failed while requesting a signed certificate from the master: cannot cre ate certificate signing request: certificatesigningrequests.certificates.k8s.io is forbidden: User “system:bootstrap:82jfrm” cannot create resource “certificatesigningrequests” i n API group “certificates.k8s.io” at the cluster scope May 9 22:48:42 k8s-master01 kubelet[128468]: E0526 22:48:42.044828 128468 kubelet.go:2244] node “k8s-master01” not found May 9 22:48:42 k8s-master01 kubelet[128468]: E0526 22:48:42.078658 128468 reflector.go:126] k8s.io/kubernetes/pkg/kubelet/kubelet.go:442: Failed to list *v1.Service: Unauthor ized May 9 22:48:42 k8s-master01 kubelet[128468]: E0526 22:48:42.079873 128468 reflector.go:126] k8s.io/kubernetes/pkg/kubelet/kubelet.go:451: Failed to list *v1.Node: Unauthorize d May 9 22:48:42 k8s-master01 kubelet[128468]: E0526 22:48:42.082683 128468 reflector.go:126] k8s.io/client-go/informers/factory.go:133: Failed to list *v1beta1.CSIDriver: Unau thorized May 9 22:48:42 k8s-master01 kubelet[128468]: E0526 22:48:42.084473 128468 reflector.go:126] k8s.io/kubernetes/pkg/kubelet/config/apiserver.go:47: Failed to list *v1.Pod: Unau thorized May 9 22:48:42 k8s-master01 kubelet[128468]: E0526 22:48:42.088466 128468 reflector.go:126] k8s.io/client-go/informers/factory.go:133: Failed to list *v1beta1.RuntimeClass: U nauthorized 解决办法是：创建一个 clusterrolebinding，将 group system:bootstrappers 和 clusterrole system:node-bootstrapper 绑定： # kubectl create clusterrolebinding kubelet-bootstrap –clusterrole=system:node-bootstrapper –group=system:bootstrappers 7) 启动 kubelet 服务 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh root@${node_node_ip} “mkdir -p ${K8S_DIR}/kubelet/kubelet-plugins/volume/exec/” ssh root@${node_node_ip} “/usr/sbin/swapoff -a” ssh root@${node_node_ip} “systemctl daemon-reload && systemctl enable kubelet && systemctl restart kubelet” done 解释说明： -> 启动服务前必须先创建工作目录； -> 关闭 swap 分区，否则 kubelet 会启动失败 (使用”journalctl -u kubelet |tail”命令查看错误日志) kubelet 启动后使用 –bootstrap-kubeconfig 向 kube-apiserver 发送 CSR 请求， 当这个 CSR 被 approve 后，kube-controller-manager 为 kubelet 创建 TLS 客户端证书、私钥和 –kubeletconfig 文件。 注意：kube-controller-manager 需要配置 –cluster-signing-cert-file 和 –cluster-signing-key-file 参数，才会为 TLS Bootstrap 创建证书和私钥。 [root@k8s-master01 work]# kubectl get csr NAME AGE REQUESTOR CONDITION csr-4wk6q 108s system:bootstrap:0zqowl Pending csr-mjtl5 110s system:bootstrap:heh41x Pending csr-rfz27 109s system:bootstrap:b46tq2 Pending [root@k8s-master01 work]# kubectl get nodes No resources found. 此时三个node节点的csr均处于 pending 状态； 8）自动 approve CSR 请求 创建三个 ClusterRoleBinding，分别用于自动 approve client、renew client、renew server 证书： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# cat > csr-crb.yaml <<EOF # Approve all CSRs for the group “system:bootstrappers” kind: ClusterRoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: auto-approve-csrs-for-group subjects: – kind: Group name: system:bootstrappers apiGroup: rbac.authorization.k8s.io roleRef: kind: ClusterRole name: system:certificates.k8s.io:certificatesigningrequests:nodeclient apiGroup: rbac.authorization.k8s.io — # To let a node of the group “system:nodes” renew its own credentials kind: ClusterRoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: node-client-cert-renewal subjects: – kind: Group name: system:nodes apiGroup: rbac.authorization.k8s.io roleRef: kind: ClusterRole name: system:certificates.k8s.io:certificatesigningrequests:selfnodeclient apiGroup: rbac.authorization.k8s.io — # A ClusterRole which instructs the CSR approver to approve a node requesting a # serving cert matching its client cert. kind: ClusterRole apiVersion: rbac.authorization.k8s.io/v1 metadata: name: approve-node-server-renewal-csr rules: – apiGroups: [“certificates.k8s.io”] resources: [“certificatesigningrequests/selfnodeserver”] verbs: [“create”] — # To let a node of the group “system:nodes” renew its own server credentials kind: ClusterRoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: node-server-cert-renewal subjects: – kind: Group name: system:nodes apiGroup: rbac.authorization.k8s.io roleRef: kind: ClusterRole name: approve-node-server-renewal-csr apiGroup: rbac.authorization.k8s.io EOF 解释说明： -> auto-approve-csrs-for-group：自动 approve node 的第一次 CSR； 注意第一次 CSR 时，请求的 Group 为 system:bootstrappers； -> node-client-cert-renewal：自动 approve node 后续过期的 client 证书，自动生成的证书 Group 为 system:nodes; -> node-server-cert-renewal：自动 approve node 后续过期的 server 证书，自动生成的证书 Group 为 system:nodes; 执行创建： [root@k8s-master01 work]# kubectl apply -f csr-crb.yaml 查看 kubelet 的情况 需要耐心等待一段时间(1-10 分钟)，三个节点的 CSR 都被自动 approved（测试时等待了很长一段时间才被自动approved） [root@k8s-master01 work]# kubectl get csr NAME AGE REQUESTOR CONDITION csr-4m4hc 37s system:node:k8s-node01 Pending csr-4wk6q 7m29s system:bootstrap:0zqowl Approved,Issued csr-h8hq6 36s system:node:k8s-node02 Pending csr-mjtl5 7m31s system:bootstrap:heh41x Approved,Issued csr-rfz27 7m30s system:bootstrap:b46tq2 Approved,Issued csr-t9p6n 36s system:node:k8s-node03 Pending 注意： Pending 的 CSR 用于创建 kubelet server 证书，需要手动 approve，后续会说到这个。 此时发现所有node节点状态均为”ready”： [root@k8s-master01 work]# kubectl get nodes NAME STATUS ROLES AGE VERSION k8s-node01 Ready <none> 3m v1.14.2 k8s-node02 Ready <none> 3m v1.14.2 k8s-node03 Ready <none> 2m59s v1.14.2 kube-controller-manager 为各node节点生成了 kubeconfig 文件和公私钥（如下在node节点上执行）： [root@k8s-node01 ~]# ls -l /etc/kubernetes/kubelet.kubeconfig -rw——- 1 root root 2310 Jun 18 17:09 /etc/kubernetes/kubelet.kubeconfig [root@k8s-node01 ~]# ls -l /etc/kubernetes/cert/|grep kubelet -rw——- 1 root root 1273 Jun 18 17:16 kubelet-client-2019-06-18-17-16-31.pem lrwxrwxrwx 1 root root 59 Jun 18 17:16 kubelet-client-current.pem -> /etc/kubernetes/cert/kubelet-client-2019-06-18-17-16-31.pem 注意：此时还没有自动生成 kubelet server 证书； 9）手动 approve server cert csr 基于安全性考虑，CSR approving controllers 不会自动 approve kubelet server 证书签名请求，需要手动 approve： [root@k8s-master01 work]# kubectl get csr NAME AGE REQUESTOR CONDITION csr-4m4hc 6m4s system:node:k8s-node01 Pending csr-4wk6q 12m system:bootstrap:0zqowl Approved,Issued csr-h8hq6 6m3s system:node:k8s-node02 Pending csr-mjtl5 12m system:bootstrap:heh41x Approved,Issued csr-rfz27 12m system:bootstrap:b46tq2 Approved,Issued csr-t9p6n 6m3s system:node:k8s-node03 Pending 记住上面执行结果为”Pending”的对应的csr的NAME名称，然后对这些csr进行手动approve [root@k8s-master01 work]# kubectl certificate approve csr-4m4hc certificatesigningrequest.certificates.k8s.io/csr-4m4hc approved [root@k8s-master01 work]# kubectl certificate approve csr-h8hq6 certificatesigningrequest.certificates.k8s.io/csr-h8hq6 approved [root@k8s-master01 work]# kubectl certificate approve csr-t9p6n certificatesigningrequest.certificates.k8s.io/csr-t9p6n approved 再次查看csr，发现所有的CSR都为approved了 [root@k8s-master01 work]# kubectl get csr NAME AGE REQUESTOR CONDITION csr-4m4hc 7m46s system:node:k8s-node01 Approved,Issued csr-4wk6q 14m system:bootstrap:0zqowl Approved,Issued csr-h8hq6 7m45s system:node:k8s-node02 Approved,Issued csr-mjtl5 14m system:bootstrap:heh41x Approved,Issued csr-rfz27 14m system:bootstrap:b46tq2 Approved,Issued csr-t9p6n 7m45s system:node:k8s-node03 Approved,Issued 再次到node节点上查看，发现已经自动生成 kubelet server 证书； [root@k8s-node01 ~]# ls -l /etc/kubernetes/cert/kubelet-* -rw——- 1 root root 1273 Jun 18 17:16 /etc/kubernetes/cert/kubelet-client-2019-06-18-17-16-31.pem lrwxrwxrwx 1 root root 59 Jun 18 17:16 /etc/kubernetes/cert/kubelet-client-current.pem -> /etc/kubernetes/cert/kubelet-client-2019-06-18-17-16-31.pem -rw——- 1 root root 1317 Jun 18 17:23 /etc/kubernetes/cert/kubelet-server-2019-06-18-17-23-13.pem lrwxrwxrwx 1 root root 59 Jun 18 17:23 /etc/kubernetes/cert/kubelet-server-current.pem -> /etc/kubernetes/cert/kubelet-server-2019-06-18-17-23-13.pem 10）kubelet 提供的 API 接口 kubelet 启动后监听多个端口，用于接收 kube-apiserver 或其它客户端发送的请求： 在node节点执行下面命令 [root@k8s-node01 ~]# netstat -lnpt|grep kubelet tcp 0 0 127.0.0.1:40831 0.0.0.0:* LISTEN 24468/kubelet tcp 0 0 172.16.60.244:10248 0.0.0.0:* LISTEN 24468/kubelet tcp 0 0 172.16.60.244:10250 0.0.0.0:* LISTEN 24468/kubelet 解释说明： -> 10248: healthz http服务端口，即健康检查服务的端口 -> 10250: kubelet服务监听的端口,api会检测他是否存活。即https服务，访问该端口时需要认证和授权（即使访问/healthz也需要）； -> 10255：只读端口，可以不用验证和授权机制，直接访问。这里配置”readOnlyPort: 0″表示未开启只读端口10255；如果配置”readOnlyPort: 10255″则打开10255端口 -> 从 K8S v1.10 开始，去除了 –cadvisor-port 参数（默认 4194 端口），不支持访问 cAdvisor UI & API。 例如执行”kubectl exec -it nginx-ds-5aedg — sh”命令时，kube-apiserver会向 kubelet 发送如下请求： POST /exec/default/nginx-ds-5aedg/my-nginx?command=sh&input=1&output=1&tty=1 kubelet 接收 10250 端口的 https 请求，可以访问如下资源： -> /pods、/runningpods -> /metrics、/metrics/cadvisor、/metrics/probes -> /spec -> /stats、/stats/container -> /logs -> /run/、/exec/, /attach/, /portForward/, /containerLogs/ 由于关闭了匿名认证，同时开启了webhook 授权，所有访问10250端口https API的请求都需要被认证和授权。 预定义的 ClusterRole system:kubelet-api-admin 授予访问 kubelet 所有 API 的权限(kube-apiserver 使用的 kubernetes 证书 User 授予了该权限)： [root@k8s-master01 work]# kubectl describe clusterrole system:kubelet-api-admin Name: system:kubelet-api-admin Labels: kubernetes.io/bootstrapping=rbac-defaults Annotations: rbac.authorization.kubernetes.io/autoupdate: true PolicyRule: Resources Non-Resource URLs Resource Names Verbs ——— —————– ————– —– nodes/log [] [] [*] nodes/metrics [] [] [*] nodes/proxy [] [] [*] nodes/spec [] [] [*] nodes/stats [] [] [*] nodes [] [] [get list watch proxy] 11) kubelet api 认证和授权 kubelet 配置了如下认证参数： -> authentication.anonymous.enabled：设置为 false，不允许匿名�访问 10250 端口； -> authentication.x509.clientCAFile：指定签名客户端证书的 CA 证书，开启 HTTPs 证书认证； -> authentication.webhook.enabled=true：开启 HTTPs bearer token 认证； 同时配置了如下授权参数： -> authroization.mode=Webhook：开启 RBAC 授权； kubelet 收到请求后，使用 clientCAFile 对证书签名进行认证，或者查询 bearer token 是否有效。如果两者都没通过，则拒绝请求，提示 Unauthorized： [root@k8s-master01 work]# curl -s –cacert /etc/kubernetes/cert/ca.pem https://172.16.60.244:10250/metrics Unauthorized [root@k8s-master01 work]# curl -s –cacert /etc/kubernetes/cert/ca.pem -H “Authorization: Bearer 123456″ https://172.16.60.244:10250/metrics Unauthorized 通过认证后，kubelet 使用 SubjectAccessReview API 向 kube-apiserver 发送请求，查询证书或 token 对应的 user、group 是否有操作资源的权限(RBAC)； 下面进行证书认证和授权： # 权限不足的证书； [root@k8s-master01 work]# curl -s –cacert /etc/kubernetes/cert/ca.pem –cert /etc/kubernetes/cert/kube-controller-manager.pem –key /etc/kubernetes/cert/kube-controller-manager-key.pem https://172.16.60.244:10250/metrics Forbidden (user=system:kube-controller-manager, verb=get, resource=nodes, subresource=metrics) # 使用部署 kubectl 命令行工具时创建的、具有最高权限的 admin 证书； [root@k8s-master01 work]# curl -s –cacert /etc/kubernetes/cert/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.244:10250/metrics|head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800”} 0 注意：–cacert、–cert、–key 的参数值必须是文件路径，否则返回 401 Unauthorized； bear token 认证和授权 创建一个 ServiceAccount，将它和 ClusterRole system:kubelet-api-admin 绑定，从而具有调用 kubelet API 的权限： [root@k8s-master01 work]# kubectl create sa kubelet-api-test [root@k8s-master01 work]# kubectl create clusterrolebinding kubelet-api-test –clusterrole=system:kubelet-api-admin –serviceaccount=default:kubelet-api-test [root@k8s-master01 work]# SECRET=$(kubectl get secrets | grep kubelet-api-test | awk {print $1}) [root@k8s-master01 work]# TOKEN=$(kubectl describe secret ${SECRET} | grep -E ^token | awk {print $2}) [root@k8s-master01 work]# echo ${TOKEN} eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.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.i_uVqjOUMLdG4lDURfhxFDOtM2addxgEquQTcpOLP_5g6UI-MjvE5jHem_Q8OtMwFs5tqlCvKJHN2IdfsRiKk_mBe_ysLQsNEoHDclZwHRVN6X84Y62q49y-ArT12YlSpfWWenw-2GawsTmORbz7AYYaU5-kgqMk95mMx57ic8uwvJYlilw4JCnkMON5ESOmgAOg30uVvsBiQVkkYTwGtAG5Tah9wADujQttBjjDOlGntpGHxj-HmZO2GivDgdrbs_UNvhzGt2maDlpP13qYv8zKiBGpSbiWOAk_olsFKQ5-dIrn04NCbh9Kkyyh9JccMSuvePaj-lgTWj5zdUfRHw 这时，再接着进行kubelet请求 [root@k8s-master01 work]# curl -s –cacert /etc/kubernetes/cert/ca.pem -H “Authorization: Bearer ${TOKEN}” https://172.16.60.244:10250/metrics|head # HELP apiserver_audit_event_total Counter of audit events generated and sent to the audit backend. # TYPE apiserver_audit_event_total counter apiserver_audit_event_total 0 # HELP apiserver_audit_requests_rejected_total Counter of apiserver requests rejected due to an error in audit logging backend. # TYPE apiserver_audit_requests_rejected_total counter apiserver_audit_requests_rejected_total 0 # HELP apiserver_client_certificate_expiration_seconds Distribution of the remaining lifetime on the certificate used to authenticate a request. # TYPE apiserver_client_certificate_expiration_seconds histogram apiserver_client_certificate_expiration_seconds_bucket{le=”0″} 0 apiserver_client_certificate_expiration_seconds_bucket{le=”1800″} 0 12）cadvisor 和 metrics cadvisor 是内嵌在 kubelet 二进制中的，统计所在节点各容器的资源(CPU、内存、磁盘、网卡)使用情况的服务。 浏览器访问https://172.16.60.244:10250/metrics 和 https://172.16.60.244:10250/metrics/cadvisor 分别返回 kubelet 和 cadvisor 的 metrics。 注意： -> kubelet.config.json 设置 authentication.anonymous.enabled 为 false，不允许匿名证书访问 10250 的 https 服务； -> 参考下面的”浏览器访问kube-apiserver安全端口”，创建和导入相关证书，然后就可以在浏览器里成功访问kube-apiserver和上面的kubelet的10250端口了。 需要通过证书方式访问kubelet的10250端口 [root@k8s-master01 ~]# curl -s –cacert /etc/kubernetes/cert/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.244:10250/metrics [root@k8s-master01 ~]# curl -s –cacert /etc/kubernetes/cert/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.244:10250/metrics/cadvisor 13）获取 kubelet 的配置 从 kube-apiserver 获取各节点 kubelet 的配置： 如果发现没有jq命令（json处理工具），可以直接yum安装jq： [root@k8s-master01 ~]# yum install -y jq 使用部署 kubectl 命令行工具时创建的、具有最高权限的 admin 证书； [root@k8s-master01 ~]# source /opt/k8s/bin/environment.sh [root@k8s-master01 ~]# curl -sSL –cacert /etc/kubernetes/cert/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem ${KUBE_APISERVER}/api/v1/nodes/k8s-node01/proxy/configz | jq .kubeletconfig|.kind=”KubeletConfiguration”|.apiVersion=”kubelet.config.k8s.io/v1beta1″ { “syncFrequency”: “1m0s”, “fileCheckFrequency”: “20s”, “httpCheckFrequency”: “20s”, “address”: “172.16.60.244”, “port”: 10250, “rotateCertificates”: true, “serverTLSBootstrap”: true, “authentication”: { “x509”: { “clientCAFile”: “/etc/kubernetes/cert/ca.pem” }, “webhook”: { “enabled”: true, “cacheTTL”: “2m0s” }, “anonymous”: { “enabled”: false } }, “authorization”: { “mode”: “Webhook”, “webhook”: { “cacheAuthorizedTTL”: “5m0s”, “cacheUnauthorizedTTL”: “30s” } }, “registryPullQPS”: 0, “registryBurst”: 20, “eventRecordQPS”: 0, “eventBurst”: 20, “enableDebuggingHandlers”: true, “enableContentionProfiling”: true, “healthzPort”: 10248, “healthzBindAddress”: “172.16.60.244”, “oomScoreAdj”: -999, “clusterDomain”: “cluster.local”, “clusterDNS”: [ “10.254.0.2” ], “streamingConnectionIdleTimeout”: “4h0m0s”, “nodeStatusUpdateFrequency”: “10s”, “nodeStatusReportFrequency”: “1m0s”, “nodeLeaseDurationSeconds”: 40, “imageMinimumGCAge”: “2m0s”, “imageGCHighThresholdPercent”: 85, “imageGCLowThresholdPercent”: 80, “volumeStatsAggPeriod”: “1m0s”, “cgroupsPerQOS”: true, “cgroupDriver”: “cgroupfs”, “cpuManagerPolicy”: “none”, “cpuManagerReconcilePeriod”: “10s”, “runtimeRequestTimeout”: “10m0s”, “hairpinMode”: “promiscuous-bridge”, “maxPods”: 220, “podCIDR”: “172.30.0.0/16”, “podPidsLimit”: -1, “resolvConf”: “/etc/resolv.conf”, “cpuCFSQuota”: true, “cpuCFSQuotaPeriod”: “100ms”, “maxOpenFiles”: 1000000, “contentType”: “application/vnd.kubernetes.protobuf”, “kubeAPIQPS”: 1000, “kubeAPIBurst”: 2000, “serializeImagePulls”: false, “evictionHard”: { “memory.available”: “100Mi” }, “evictionPressureTransitionPeriod”: “5m0s”, “enableControllerAttachDetach”: true, “makeIPTablesUtilChains”: true, “iptablesMasqueradeBit”: 14, “iptablesDropBit”: 15, “failSwapOn”: true, “containerLogMaxSize”: “20Mi”, “containerLogMaxFiles”: 10, “configMapAndSecretChangeDetectionStrategy”: “Watch”, “enforceNodeAllocatable”: [ “pods” ], “kind”: “KubeletConfiguration”, “apiVersion”: “kubelet.config.k8s.io/v1beta1″ } 或者直接执行下面语句：（https://172.16.60.250:8443 就是变量${KUBE_APISERVER}） [root@k8s-master01 ~]# curl -sSL –cacert /etc/kubernetes/cert/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.250:8443/api/v1/nodes/k8s-node01/proxy/configz | jq .kubeletconfig|.kind=”KubeletConfiguration”|.apiVersion=”kubelet.config.k8s.io/v1beta1″ [root@k8s-master01 ~]# curl -sSL –cacert /etc/kubernetes/cert/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.250:8443/api/v1/nodes/k8s-node02/proxy/configz | jq .kubeletconfig|.kind=”KubeletConfiguration”|.apiVersion=”kubelet.config.k8s.io/v1beta1″ [root@k8s-master01 ~]# curl -sSL –cacert /etc/kubernetes/cert/ca.pem –cert /opt/k8s/work/admin.pem –key /opt/k8s/work/admin-key.pem https://172.16.60.250:8443/api/v1/nodes/k8s-node03/proxy/configz | jq .kubeletconfig|.kind=”KubeletConfiguration”|.apiVersion=”kubelet.config.k8s.io/v1beta1”

9.3 – 浏览器访问kube-apiserver等安全端口，创建和导入证书的做法

浏览器访问 kube-apiserver 的安全端口 6443 （代理端口是8443）时，提示证书不被信任：

这是因为 kube-apiserver 的 server 证书是我们创建的根证书 ca.pem 签名的，需要将根证书 ca.pem 导入操作系统，并设置永久信任。

这里说下Mac OS系统客户机上导入证书的方法:

1）点击Mac本上的”钥匙串访问” -> “系统” -> “证书” -> “kebernetes“(双击里面的”信任“，改成”始终信任“),如下图：

清除浏览器缓存，再次访问，发现证书已经被信任了！(红色感叹号已经消失了)

2）需要给浏览器生成一个 client 证书，访问 apiserver 的 6443 https 端口时使用。

这里使用部署 kubectl 命令行工具时创建的 admin 证书、私钥和上面的 ca 证书，创建一个浏览器可以使用 PKCS#12/PFX 格式的证书:

[root@k8s-master01 ~]# cd /opt/k8s/work/ [root@k8s-master01 work]# openssl pkcs12 -export -out admin.pfx -inkey admin-key.pem -in admin.pem -certfile ca.pem Enter Export Password: # 这里输入自己设定的任意密码，比如”123456″ Verifying – Enter Export Password: # 确认密码: 123456 [root@k8s-master01 work]# ll admin.pfx -rw-r–r– 1 root root 3613 Jun 23 23:56 admin.pfx

将在k8s-master01服务器上生成的client证书admin.pfx拷贝到Mac本机，导入到”钥匙串访问” -> “系统” -> “证书” 里面 (导入时会提示输入admin.pfx证书的密码，即”123456″)，如下图:

清除浏览器历史记录，一定要重启浏览器，接着访问apiserver地址，接着会提示选择一个浏览器证书，这里选中上面导入的”admin.pfx”, 然后再次访问apiserver，发现相应的metrics数据就成功显示出来了！！(注意，如果失败了。则可以删除证书，然后重新生成，重新导入再跟着操作步骤来一遍，清除浏览器缓存，重启浏览器，选择导入的证书，再次访问即可！）

同样的，再上面apiserver访问的client证书导入到本地浏览器后，再访问kubelet的10250端口的metric时，也会提示选择导入的证书”admin.pfx”，然后就会正常显示对应的metrics数据了。（k8s集群的其他组件metrics的https证书方式方式同理！）

9.4 – 部署 kube-proxy 组件

kube-proxy运行在所有的node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。下面部署命令均在k8s-master01节点上执行，然后远程分发文件和执行命令。

1）下载和分发 kube-proxy 二进制文件 [root@k8s-master01 ~]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” scp kubernetes/server/bin/kube-proxy root@${node_node_ip}:/opt/k8s/bin/ ssh root@${node_node_ip} “chmod +x /opt/k8s/bin/*” done 2) 创建 kube-proxy 证书 创建证书签名请求： [root@k8s-master01 ~]# cd /opt/k8s/work [root@k8s-master01 work]# cat > kube-proxy-csr.json <<EOF { “CN”: “system:kube-proxy”, “key”: { “algo”: “rsa”, “size”: 2048 }, “names”: [ { “C”: “CN”, “ST”: “BeiJing”, “L”: “BeiJing”, “O”: “k8s”, “OU”: “4Paradigm” } ] } EOF 注意： CN：指定该证书的 User 为 system:kube-proxy； 预定义的 RoleBinding system:node-proxier 将User system:kube-proxy 与 Role system:node-proxier 绑定，该 Role 授予了调用 kube-apiserver Proxy 相关 API 的权限； 该证书只会被 kube-proxy 当做 client 证书使用，所以 hosts 字段为空； 生成证书和私钥： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# cfssl gencert -ca=/opt/k8s/work/ca.pem -ca-key=/opt/k8s/work/ca-key.pem -config=/opt/k8s/work/ca-config.json -profile=kubernetes kube-proxy-csr.json | cfssljson -bare kube-proxy [root@k8s-master01 work]# ll kube-proxy* -rw-r–r– 1 root root 1013 Jun 24 20:21 kube-proxy.csr -rw-r–r– 1 root root 218 Jun 24 20:21 kube-proxy-csr.json -rw——- 1 root root 1679 Jun 24 20:21 kube-proxy-key.pem -rw-r–r– 1 root root 1411 Jun 24 20:21 kube-proxy.pem 3）创建和分发 kubeconfig 文件 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# kubectl config set-cluster kubernetes –certificate-authority=/opt/k8s/work/ca.pem –embed-certs=true –server=${KUBE_APISERVER} –kubeconfig=kube-proxy.kubeconfig [root@k8s-master01 work]# kubectl config set-credentials kube-proxy –client-certificate=kube-proxy.pem –client-key=kube-proxy-key.pem –embed-certs=true –kubeconfig=kube-proxy.kubeconfig [root@k8s-master01 work]# kubectl config set-context default –cluster=kubernetes –user=kube-proxy –kubeconfig=kube-proxy.kubeconfig [root@k8s-master01 work]# kubectl config use-context default –kubeconfig=kube-proxy.kubeconfig 注意：–embed-certs=true：将 ca.pem 和 admin.pem 证书内容嵌入到生成的 kubectl-proxy.kubeconfig 文件中(不加时，写入的是证书文件路径)； 分发 kubeconfig 文件： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_name in ${NODE_NODE_NAMES[@]} do echo “>>> ${node_node_name}” scp kube-proxy.kubeconfig root@${node_node_name}:/etc/kubernetes/ done 4）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。 创建 kube-proxy config 文件模板： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# 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_NODE_IP## healthzBindAddress: ##NODE_NODE_IP##:10256 metricsBindAddress: ##NODE_NODE_IP##:10249 enableProfiling: true clusterCIDR: ${CLUSTER_CIDR} hostnameOverride: ##NODE_NODE_NAME## mode: “ipvs” portRange: “” kubeProxyIPTablesConfiguration: masqueradeAll: false kubeProxyIPVSConfiguration: scheduler: rr excludeCIDRs: [] EOF 注意： 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： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for (( i=0; i < 3; i++ )) do echo “>>> ${NODE_NODE_NAMES[i]}” sed -e “s/##NODE_NODE_NAME##/${NODE_NODE_NAMES[i]}/” -e “s/##NODE_NODE_IP##/${NODE_NODE_IPS[i]}/” kube-proxy-config.yaml.template > kube-proxy-config-${NODE_NODE_NAMES[i]}.yaml.template scp kube-proxy-config-${NODE_NODE_NAMES[i]}.yaml.template root@${NODE_NODE_NAMES[i]}:/etc/kubernetes/kube-proxy-config.yaml done [root@k8s-master01 work]# ll kube-proxy-config-k8s-node0* -rw-r–r– 1 root root 500 Jun 24 20:27 kube-proxy-config-k8s-node01.yaml.template -rw-r–r– 1 root root 500 Jun 24 20:27 kube-proxy-config-k8s-node02.yaml.template -rw-r–r– 1 root root 500 Jun 24 20:27 kube-proxy-config-k8s-node03.yaml.template 5）创建和分发 kube-proxy systemd unit 文件 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# 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： [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_name in ${NODE_NODE_NAMES[@]} do echo “>>> ${node_node_name}” scp kube-proxy.service root@${node_node_name}:/etc/systemd/system/ done 6）启动 kube-proxy 服务 [root@k8s-master01 work]# cd /opt/k8s/work [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh root@${node_node_ip} “mkdir -p ${K8S_DIR}/kube-proxy” ssh root@${node_node_ip} “modprobe ip_vs_rr” ssh root@${node_node_ip} “systemctl daemon-reload && systemctl enable kube-proxy && systemctl restart kube-proxy” done 注意：启动服务前必须先创建工作目录； 检查启动结果： [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh root@${node_node_ip} “systemctl status kube-proxy|grep Active” done 预期结果： >>> 172.16.60.244 Active: active (running) since Mon 2019-06-24 20:35:31 CST; 2min 0s ago >>> 172.16.60.245 Active: active (running) since Mon 2019-06-24 20:35:30 CST; 2min 0s ago >>> 172.16.60.246 Active: active (running) since Mon 2019-06-24 20:35:32 CST; 1min 59s ago 确保状态为 active (running)，否则查看日志，确认原因（journalctl -u kube-proxy） 7）查看监听端口（在任意一台node节点上查看） [root@k8s-node01 ~]# netstat -lnpt|grep kube-prox tcp 0 0 172.16.60.244:10249 0.0.0.0:* LISTEN 3830/kube-proxy tcp 0 0 172.16.60.244:10256 0.0.0.0:* LISTEN 3830/kube-proxy 需要注意： 10249：该端口用于http prometheus metrics port; 10256：该端口用于http healthz port; 8）查看 ipvs 路由规则 [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh root@${node_node_ip} “/usr/sbin/ipvsadm -ln” done 预期输出： >>> 172.16.60.244 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 -> 172.16.60.241:6443 Masq 1 0 0 -> 172.16.60.242:6443 Masq 1 0 0 -> 172.16.60.243:6443 Masq 1 0 0 >>> 172.16.60.245 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 -> 172.16.60.241:6443 Masq 1 0 0 -> 172.16.60.242:6443 Masq 1 0 0 -> 172.16.60.243:6443 Masq 1 0 0 >>> 172.16.60.246 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 -> 172.16.60.241:6443 Masq 1 0 0 -> 172.16.60.242:6443 Masq 1 0 0 -> 172.16.60.243:6443 Masq 1 0 0 由上面可以看出：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；

十、验证Kubernetes集群功能

使用 daemonset 验证 master 和 worker 节点是否工作正常。 1）检查节点状态 [root@k8s-master01 ~]# kubectl get nodes NAME STATUS ROLES AGE VERSION k8s-node01 Ready <none> 6d3h v1.14.2 k8s-node02 Ready <none> 6d3h v1.14.2 k8s-node03 Ready <none> 6d3h v1.14.2 各node节点状态都为 Ready 时正常。 2）创建测试文件 [root@k8s-master01 ~]# cd /opt/k8s/work [root@k8s-master01 work]# cat > nginx-ds.yml <<EOF apiVersion: v1 kind: Service metadata: name: nginx-ds labels: app: nginx-ds spec: type: NodePort selector: app: nginx-ds ports: – name: http port: 80 targetPort: 80 — apiVersion: extensions/v1beta1 kind: DaemonSet metadata: name: nginx-ds labels: addonmanager.kubernetes.io/mode: Reconcile spec: template: metadata: labels: app: nginx-ds spec: containers: – name: my-nginx image: nginx:1.7.9 ports: – containerPort: 80 EOF 执行测试 [root@k8s-master01 work]# kubectl create -f nginx-ds.yml 3）检查各节点的 Pod IP 连通性 稍微等一会儿，或者或刷几次下面的命令，才会显示出Pod的IP信息 [root@k8s-master01 work]# kubectl get pods -o wide|grep nginx-ds nginx-ds-4lf8z 1/1 Running 0 46s 172.30.56.2 k8s-node02 <none> <none> nginx-ds-6kfsw 1/1 Running 0 46s 172.30.72.2 k8s-node03 <none> <none> nginx-ds-xqdgw 1/1 Running 0 46s 172.30.88.2 k8s-node01 <none> <none> 可见，nginx-ds的 Pod IP分别是 172.30.56.2、172.30.72.2、172.30.88.2，在所有 Node 上分别 ping 这三个 IP，看是否连通： [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh ${node_node_ip} “ping -c 1 172.30.56.2” ssh ${node_node_ip} “ping -c 1 172.30.72.2” ssh ${node_node_ip} “ping -c 1 172.30.88.2” done 预期输出结果： >>> 172.16.60.244 PING 172.30.56.2 (172.30.56.2) 56(84) bytes of data. 64 bytes from 172.30.56.2: icmp_seq=1 ttl=63 time=0.542 ms — 172.30.56.2 ping statistics — 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.542/0.542/0.542/0.000 ms PING 172.30.72.2 (172.30.72.2) 56(84) bytes of data. 64 bytes from 172.30.72.2: icmp_seq=1 ttl=63 time=0.654 ms — 172.30.72.2 ping statistics — 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.654/0.654/0.654/0.000 ms PING 172.30.88.2 (172.30.88.2) 56(84) bytes of data. 64 bytes from 172.30.88.2: icmp_seq=1 ttl=64 time=0.103 ms — 172.30.88.2 ping statistics — 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.103/0.103/0.103/0.000 ms >>> 172.16.60.245 PING 172.30.56.2 (172.30.56.2) 56(84) bytes of data. 64 bytes from 172.30.56.2: icmp_seq=1 ttl=64 time=0.106 ms — 172.30.56.2 ping statistics — 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.106/0.106/0.106/0.000 ms PING 172.30.72.2 (172.30.72.2) 56(84) bytes of data. 64 bytes from 172.30.72.2: icmp_seq=1 ttl=63 time=0.408 ms — 172.30.72.2 ping statistics — 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.408/0.408/0.408/0.000 ms PING 172.30.88.2 (172.30.88.2) 56(84) bytes of data. 64 bytes from 172.30.88.2: icmp_seq=1 ttl=63 time=0.345 ms — 172.30.88.2 ping statistics — 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.345/0.345/0.345/0.000 ms >>> 172.16.60.246 PING 172.30.56.2 (172.30.56.2) 56(84) bytes of data. 64 bytes from 172.30.56.2: icmp_seq=1 ttl=63 time=0.350 ms — 172.30.56.2 ping statistics — 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.350/0.350/0.350/0.000 ms PING 172.30.72.2 (172.30.72.2) 56(84) bytes of data. 64 bytes from 172.30.72.2: icmp_seq=1 ttl=64 time=0.105 ms — 172.30.72.2 ping statistics — 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.105/0.105/0.105/0.000 ms PING 172.30.88.2 (172.30.88.2) 56(84) bytes of data. 64 bytes from 172.30.88.2: icmp_seq=1 ttl=63 time=0.584 ms — 172.30.88.2 ping statistics — 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.584/0.584/0.584/0.000 ms 4）检查服务 IP 和端口可达性 [root@k8s-master01 work]# kubectl get svc |grep nginx-ds nginx-ds NodePort 10.254.41.83 <none> 80:30876/TCP 4m24s 可见： Service Cluster IP：10.254.41.83 服务端口：80 NodePort 端口：30876 在所有 Node 上 curl Service IP： [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh ${node_node_ip} “curl -s 10.254.41.83” done 预期输出: nginx欢迎页面内容。 5）检查服务的 NodePort 可达性 在所有 Node 上执行： [root@k8s-master01 work]# source /opt/k8s/bin/environment.sh [root@k8s-master01 work]# for node_node_ip in ${NODE_NODE_IPS[@]} do echo “>>> ${node_node_ip}” ssh ${node_node_ip} “curl -s ${node_node_ip}:30876” done 预期输出: nginx 欢迎页面内容。

点击查看 Kubernetes(K8S)容器集群管理环境完整部署详细教程-下篇