下面的操作依托于上一篇文章

创建 kube-apiserver 证书

cd /opt/k8s/work

source /opt/k8s/bin/environment.sh

cat > kubernetes-csr.json <<EOF

{

  "CN": "kubernetes",

  "hosts": [

    "127.0.0.1",

    "10.0.20.10",

    "10.0.20.11",

    "10.0.20.12",

    "10.0.20.13",

    "vip.k8s.com",

    "node01.k8s.com",

    "node02.k8s.com",

    "node03.k8s.com",

    "10.254.0.1",

    "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

#需要将集群的所有IP及VIP添域名加进去

#如果要添加注意最后的逗号，不要忘记添加，否则下一步报错

hosts 字段指定授权使用该证书的IP和域名列表，这里列出了master节点IP、kubernetes服务的IP和域名

kubernetes serviceIP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

$ kubectl get svc kubernetes

NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE

kubernetes   ClusterIP   10.254.0.1           443/TCP   31d

生成证书和私钥

cd /opt/k8s/work

source /opt/k8s/bin/environment.sh

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

ls kubernetes*pem

将生成的证书和私钥文件拷贝到所有master节点

cd /opt/k8s/work

source /opt/k8s/bin/environment.sh

for node_ip in ${MASTER_IPS[@]}

  do

    echo ">>> ${node_ip}"

    ssh root@${node_ip} "mkdir -p /etc/kubernetes/cert"

    scp kubernetes*.pem root@${node_ip}:/etc/kubernetes/cert/

  done

创建加密配置文件

cd /opt/k8s/work

source /opt/k8s/bin/environment.sh

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

cd /opt/k8s/work

source /opt/k8s/bin/environment.sh

for node_ip in ${MASTER_IPS[@]}

  do

    echo ">>> ${node_ip}"

    scp encryption-config.yaml root@${node_ip}:/etc/kubernetes/

  done

创建审计策略文件

cd /opt/k8s/work

source /opt/k8s/bin/environment.sh

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

  # Don't log HPA fetching metrics.

  - level: None

    resources:

      - group: metrics.k8s.io

    users:

      - 'system:kube-controller-manager'

    verbs:

      - get

      - list

  # Don't log these read-only URLs.

  - level: None

    nonResourceURLs:

      - '/healthz*'

      - /version

      - '/swagger*'

  # Don't log events requests.

  - level: None

    resources:

      - group: ""

        resources:

          - events

  # node and pod status calls from nodes are high-volume and can be large, don't 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, don't 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：

cd /opt/k8s/work

source /opt/k8s/bin/environment.sh

for node_ip in ${MASTER_IPS[@]}

  do

    echo ">>> ${node_ip}"

    scp audit-policy.yaml root@${node_ip}:/etc/kubernetes/audit-policy.yaml

  done

分发 kube-apiserver 二进制文件

把 kube-apiserver 二进制执行文件分发到所有 master 节点上

cd /opt/k8s/work/

source /opt/k8s/bin/environment.sh

for node_ip in ${MASTER_IPS[@]}

  do

    echo ">>> ${node_ip}"

    scp kubernetes/server/bin/kube-apiserver root@${node_ip}:/opt/k8s/bin/

  done

创建后续访问 metrics-server 使用的证书

创建证书签名请求:

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 名称需要位于 kube-apiserver 的 --requestheader-allowed-names 参数中，否则后续访问 metrics 时会提示权限不足。

生成证书和私钥：

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

ls proxy-client*.pem

将生成的证书和私钥文件拷贝到所有 master 节点：

source /opt/k8s/bin/environment.sh

for node_ip in ${MASTER_IPS[@]}

  do

    echo ">>> ${node_ip}"

    scp proxy-client*.pem root@${node_ip}:/etc/kubernetes/cert/

  done

创建 kube-apiserver systemd unit 模板文件

cd /opt/k8s/work

source /opt/k8s/bin/environment.sh

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_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_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-truncate-enabled \\

  --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="aggregator" \\

  --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 \\

  --v=2

Restart=on-failure

RestartSec=10

Type=notify

LimitNOFILE=65536

[Install]

WantedBy=multi-user.target

EOF

--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；
--requestheader-allowed-names：不能为空，值为逗号分割的 --proxy-client-cert-file 证书的 CN 名称，这里设置为 "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；

如果 kube-apiserver 机器没有运行 kube-proxy，则还需要添加 --enable-aggregator-routing=true 参数；

关于 --requestheader-XXX 相关参数，参考：

注意：

requestheader-client-ca-file 指定的 CA 证书，必须具有 client auth and server auth；
如果 --requestheader-allowed-names 不为空，且 --proxy-client-cert-file 证书的 CN 名称不在 allowed-names 中，则后续查看 node 或 pods 的 metrics 失败，提示：

[root@zhangjun-k8s01 1.8+]# kubectl top nodes

Error from server (Forbidden): nodes.metrics.k8s.io is forbidden: User "aggregator" cannot list resource "nodes" in API group "metrics.k8s.io" at the cluster scope

为各节点创建和分发 kube-apiserver systemd unit 文件

cd /opt/k8s/work

source /opt/k8s/bin/environment.sh

for (( i=0; i < 3; i++ ))

  do

    sed -e "s/##NODE_NAME##/${NODE_NAMES[i]}/" -e "s/##NODE_IP##/${NODE_IPS[i]}/" kube-apiserver.service.template > kube-apiserver-${NODE_IPS[i]}.service

  done

ls kube-apiserver*.service

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；

分发生成的 systemd unit 文件：

cd /opt/k8s/work

source /opt/k8s/bin/environment.sh

for node_ip in ${MASTER_IPS[@]}

  do

    echo ">>> ${node_ip}"

    scp kube-apiserver-${node_ip}.service root@${node_ip}:/etc/systemd/system/kube-apiserver.service

  done

文件重命名为 kube-apiserver.service;

启动apiserver

source /opt/k8s/bin/environment.sh

for node_ip in ${MASTER_IPS[@]}

  do

    echo ">>> ${node_ip}"

    ssh root@${node_ip} "mkdir -p ${K8S_DIR}/kube-apiserver"

    ssh root@${node_ip} "systemctl daemon-reload && systemctl enable kube-apiserver && systemctl restart kube-apiserver"

  done

检查服务是否正常

for node_ip in ${MASTER_IPS[@]}

  do

    echo ">>> ${node_ip}"

    ssh root@${node_ip} "systemctl status kube-apiserver |grep 'Active:'"

  done

输出结果如下

[root@node01 work]# for node_ip in ${MASTER_IPS[@]}

>   do

>     echo ">>> ${node_ip}"

>     ssh root@${node_ip} "systemctl status kube-apiserver |grep 'Active:'"

>   done

>>> 10.0.20.11

   Active: active (running) since Thu 2019-12-05 14:29:01 CST; 29s ago

>>> 10.0.20.12

   Active: active (running) since Thu 2019-12-05 14:29:27 CST; 3s ago

>>> 10.0.20.13

   Active: active (running) since Thu 2019-12-05 14:29:27 CST; 3s ago

查看端口apiserver 启动的端口:

for node_ip in ${MASTER_IPS[@]}

  do

    echo ">>> ${node_ip}"

    ssh root@${node_ip} "netstat -lntup|grep kube-apiserver |grep '6443'"

  done

[root@node01 work]# for node_ip in ${MASTER_IPS[@]}

>   do

>     echo ">>> ${node_ip}"

>     ssh root@${node_ip} "netstat -lntup|grep kube-apiserver |grep '6443'"

>   done

>>> 10.0.20.11

tcp        0      0 10.0.20.11:6443         0.0.0.0:*               LISTEN      2891/kube-apiserver

>>> 10.0.20.12

tcp        0      0 10.0.20.12:6443         0.0.0.0:*               LISTEN      2391/kube-apiserver

>>> 10.0.20.13

tcp        0      0 10.0.20.13:6443         0.0.0.0:*               LISTEN      2436/kube-apiserver

打印kube-apiserver写入etcd数据

source /opt/k8s/bin/environment.sh

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

巴特西

kube-apiserver 集群服务安装