Kubernetes v1.12/v1.13 二進制部署集群（HTTPS+RBAC）

官方提供的幾種Kubernetes部署方式

• minikube

Minikube是一個工具，可以在本地快速運行一個單點的Kubernetes，嘗試Kubernetes或日常開發的用戶使用。不能用于生產環境。

官方地址：https://kubernetes.io/docs/setup/minikube/

• kubeadm

Kubeadm也是一個工具，提供kubeadm init和kubeadm join，用于快速部署Kubernetes集群。

官方地址：https://kubernetes.io/docs/reference/setup-tools/kubeadm/kubeadm/

• 二進制包

從官方下載發行版的二進制包，手動部署每個組件，組成Kubernetes集群。

小結：
生產環境中部署Kubernetes集群，只有Kubeadm和二進制包可選，Kubeadm降低部署門檻，但屏蔽了很多細節，遇到問題很難排查。我們這里使用二進制包部署Kubernetes集群，我也是推薦大家使用這種方式，雖然手動部署麻煩點，但學習很多工作原理，更有利于后期維護。

軟件環境

服務器角色

? 架構圖

1. 部署Etcd集群

使用cfssl來生成自簽證書，先下載cfssl工具：

wget https://pkg.cfssl.org/R1.2/cfssl_linux-amd64
wget https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64
wget https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64
chmod +x cfssl_linux-amd64 cfssljson_linux-amd64 cfssl-certinfo_linux-amd64
mv cfssl_linux-amd64 /usr/local/bin/cfssl
mv cfssljson_linux-amd64 /usr/local/bin/cfssljson
mv cfssl-certinfo_linux-amd64 /usr/bin/cfssl-certinfo

1.1 生成證書

創建以下三個文件：

# cat ca-config.json
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "www": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}

# cat ca-csr.json
{
    "CN": "etcd CA",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing"
        }
    ]
}

# cat server-csr.json
{
    "CN": "etcd",
    "hosts": [
    "192.168.31.63",
    "192.168.31.65",
    "192.168.31.66"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "BeiJing",
            "ST": "BeiJing"
        }
    ]
}

生成證書：

cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=www server-csr.json | cfssljson -bare server
# ls *pem
ca-key.pem  ca.pem  server-key.pem  server.pem

證書這塊知道怎么生成、怎么用即可，建議暫時不必過多研究。

1.2 部署Etcd

二進制包下載地址：https://github.com/coreos/etcd/releases/tag/v3.2.12

以下部署步驟在規劃的三個etcd節點操作一樣，唯一不同的是etcd配置文件中的服務器IP要寫當前的：

解壓二進制包：

# mkdir /opt/etcd/{bin,cfg,ssl} -p
# tar zxvf etcd-v3.2.12-linux-amd64.tar.gz
# mv etcd-v3.2.12-linux-amd64/{etcd,etcdctl} /opt/etcd/bin/

創建etcd配置文件：

# cat /opt/etcd/cfg/etcd   
#[Member]
ETCD_NAME="etcd01"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.31.63:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.31.63:2379"

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.31.63:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.31.63:2379"
ETCD_INITIAL_CLUSTER="etcd01=https://192.168.31.63:2380,etcd02=https://192.168.31.65:2380,etcd03=https://192.168.31.66:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"

• ETCD_NAME 節點名稱
• ETCD_DATA_DIR 數據目錄
• ETCD_LISTEN_PEER_URLS 集群通信監聽地址
• ETCD_LISTEN_CLIENT_URLS 客戶端訪問監聽地址
• ETCD_INITIAL_ADVERTISE_PEER_URLS 集群通告地址
• ETCD_ADVERTISE_CLIENT_URLS 客戶端通告地址
• ETCD_INITIAL_CLUSTER 集群節點地址
• ETCD_INITIAL_CLUSTER_TOKEN 集群Token
• ETCD_INITIAL_CLUSTER_STATE 加入集群的當前狀態，new是新集群，existing表示加入已有集群

systemd管理etcd：

# cat /usr/lib/systemd/system/etcd.service 
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target

[Service]
Type=notify
EnvironmentFile=/opt/etcd/cfg/etcd
ExecStart=/opt/etcd/bin/etcd \
--name=${ETCD_NAME} \
--data-dir=${ETCD_DATA_DIR} \
--listen-peer-urls=${ETCD_LISTEN_PEER_URLS} \
--listen-client-urls=${ETCD_LISTEN_CLIENT_URLS},http://127.0.0.1:2379 \
--advertise-client-urls=${ETCD_ADVERTISE_CLIENT_URLS} \
--initial-advertise-peer-urls=${ETCD_INITIAL_ADVERTISE_PEER_URLS} \
--initial-cluster=${ETCD_INITIAL_CLUSTER} \
--initial-cluster-token=${ETCD_INITIAL_CLUSTER_TOKEN} \
--initial-cluster-state=new \
--cert-file=/opt/etcd/ssl/server.pem \
--key-file=/opt/etcd/ssl/server-key.pem \
--peer-cert-file=/opt/etcd/ssl/server.pem \
--peer-key-file=/opt/etcd/ssl/server-key.pem \
--trusted-ca-file=/opt/etcd/ssl/ca.pem \
--peer-trusted-ca-file=/opt/etcd/ssl/ca.pem
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

把剛才生成的證書拷貝到配置文件中的位置：

# cp ca*pem server*pem /opt/etcd/ssl

啟動并設置開啟啟動：

# systemctl start etcd
# systemctl enable etcd

都部署完成后，檢查etcd集群狀態：

# /opt/etcd/bin/etcdctl \
--ca-file=ca.pem --cert-file=server.pem --key-file=server-key.pem \
--endpoints="https://192.168.31.63:2379,https://192.168.31.65:2379,https://192.168.31.66:2379" \
cluster-health
member 18218cfabd4e0dea is healthy: got healthy result from https://192.168.31.63:2379
member 541c1c40994c939b is healthy: got healthy result from https://192.168.31.65:2379
member a342ea2798d20705 is healthy: got healthy result from https://192.168.31.66:2379
cluster is healthy

如果輸出上面信息，就說明集群部署成功。如果有問題第一步先看日志：/var/log/message 或 journalctl -u etcd

2. 在Node安裝Docker

# yum install -y yum-utils device-mapper-persistent-data lvm2
# yum-config-manager \
    --add-repo \
    https://download.docker.com/linux/centos/docker-ce.repo
# yum install docker-ce -y
# curl -sSL https://get.daocloud.io/daotools/set_mirror.sh | sh -s http://bc437cce.m.daocloud.io
# systemctl start docker
# systemctl enable docker

3. 部署Flannel網絡

工作原理：

Falnnel要用etcd存儲自身一個子網信息，所以要保證能成功連接Etcd，寫入預定義子網段：

# /opt/etcd/bin/etcdctl \
--ca-file=ca.pem --cert-file=server.pem --key-file=server-key.pem \
--endpoints="https://192.168.31.63:2379,https://192.168.31.65:2379,https://192.168.31.66:2379" \
set /coreos.com/network/config  '{ "Network": "172.17.0.0/16", "Backend": {"Type": "vxlan"}}'

以下部署步驟在規劃的每個node節點都操作。

下載二進制包：

# wget https://github.com/coreos/flannel/releases/download/v0.10.0/flannel-v0.10.0-linux-amd64.tar.gz
# tar zxvf flannel-v0.9.1-linux-amd64.tar.gz
# mv flanneld mk-docker-opts.sh /opt/kubernetes/bin

配置Flannel：

# cat /opt/kubernetes/cfg/flanneld
FLANNEL_OPTIONS="--etcd-endpoints=https://192.168.31.63:2379,https://192.168.31.65:2379,https://192.168.31.66:2379 -etcd-cafile=/opt/etcd/ssl/ca.pem -etcd-certfile=/opt/etcd/ssl/server.pem -etcd-keyfile=/opt/etcd/ssl/server-key.pem"

systemd管理Flannel：

# cat /usr/lib/systemd/system/flanneld.service
[Unit]
Description=Flanneld overlay address etcd agent
After=network-online.target network.target
Before=docker.service

[Service]
Type=notify
EnvironmentFile=/opt/kubernetes/cfg/flanneld
ExecStart=/opt/kubernetes/bin/flanneld --ip-masq $FLANNEL_OPTIONS
ExecStartPost=/opt/kubernetes/bin/mk-docker-opts.sh -k DOCKER_NETWORK_OPTIONS -d /run/flannel/subnet.env
Restart=on-failure

[Install]
WantedBy=multi-user.target

配置Docker啟動指定子網段：

# cat /usr/lib/systemd/system/docker.service 

[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target firewalld.service
Wants=network-online.target

[Service]
Type=notify
EnvironmentFile=/run/flannel/subnet.env
ExecStart=/usr/bin/dockerd $DOCKER_NETWORK_OPTIONS
ExecReload=/bin/kill -s HUP $MAINPID
LimitNOFILE=infinity
LimitNPROC=infinity
LimitCORE=infinity
TimeoutStartSec=0
Delegate=yes
KillMode=process
Restart=on-failure
StartLimitBurst=3
StartLimitInterval=60s

[Install]
WantedBy=multi-user.target

重啟flannel和docker：

# systemctl daemon-reload
# systemctl start flanneld
# systemctl enable flanneld
# systemctl restart docker

檢查是否生效：

# ps -ef |grep docker
root     20941     1  1 Jun28 ?        09:15:34 /usr/bin/dockerd --bip=172.17.34.1/24 --ip-masq=false --mtu=1450
# ip addr
3607: flannel.1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UNKNOWN 
    link/ether 8a:2e:3d:09:dd:82 brd ff:ff:ff:ff:ff:ff
    inet 172.17.34.0/32 scope global flannel.1
       valid_lft forever preferred_lft forever
3608: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UP 
    link/ether 02:42:31:8f:d3:02 brd ff:ff:ff:ff:ff:ff
    inet 172.17.34.1/24 brd 172.17.34.255 scope global docker0
       valid_lft forever preferred_lft forever
    inet6 fe80::42:31ff:fe8f:d302/64 scope link 
       valid_lft forever preferred_lft forever

確保docker0與flannel.1在同一網段。
測試不同節點互通，在當前節點訪問另一個Node節點docker0 IP：

# ping 172.17.58.1
PING 172.17.58.1 (172.17.58.1) 56(84) bytes of data.
64 bytes from 172.17.58.1: icmp_seq=1 ttl=64 time=0.263 ms
64 bytes from 172.17.58.1: icmp_seq=2 ttl=64 time=0.204 ms

如果能通說明Flannel部署成功。如果不通檢查下日志：journalctl -u flannel

4. 在Master節點部署組件

在部署Kubernetes之前一定要確保etcd、flannel、docker是正常工作的，否則先解決問題再繼續。

4.1 生成證書

創建CA證書：

# cat ca-config.json
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "kubernetes": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}

# cat ca-csr.json
{
    "CN": "kubernetes",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}

# cfssl gencert -initca ca-csr.json | cfssljson -bare ca -

生成apiserver證書：

# cat server-csr.json
{
    "CN": "kubernetes",
    "hosts": [
      "10.0.0.1",
      "127.0.0.1",
      "192.168.31.63",
      "kubernetes",
      "kubernetes.default",
      "kubernetes.default.svc",
      "kubernetes.default.svc.cluster",
      "kubernetes.default.svc.cluster.local"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "BeiJing",
            "ST": "BeiJing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes server-csr.json | cfssljson -bare server

生成kube-proxy證書：

# cat kube-proxy-csr.json
{
  "CN": "system:kube-proxy",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing",
      "ST": "BeiJing",
      "O": "k8s",
      "OU": "System"
    }
  ]
}

# cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-proxy-csr.json | cfssljson -bare kube-proxy

最終生成以下證書文件：

# ls *pem
ca-key.pem  ca.pem  kube-proxy-key.pem  kube-proxy.pem  server-key.pem  server.pem

4.2 部署apiserver組件

下載二進制包：https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.12.md
下載這個包（kubernetes-server-linux-amd64.tar.gz）就夠了，包含了所需的所有組件。

# mkdir /opt/kubernetes/{bin,cfg,ssl} -p
# tar zxvf kubernetes-server-linux-amd64.tar.gz
# cd kubernetes/server/bin
# cp kube-apiserver kube-scheduler kube-controller-manager kubectl /opt/kubernetes/bin

創建token文件，用途后面會講到：

# cat /opt/kubernetes/cfg/token.csv
674c457d4dcf2eefe4920d7dbb6b0ddc,kubelet-bootstrap,10001,"system:kubelet-bootstrap"

第一列：隨機字符串，自己可生成
第二列：用戶名
第三列：UID
第四列：用戶組

創建apiserver配置文件：

# cat /opt/kubernetes/cfg/kube-apiserver 

KUBE_APISERVER_OPTS="--logtostderr=true \
--v=4 \
--etcd-servers=https://192.168.31.63:2379,https://192.168.31.65:2379,https://192.168.31.66:2379 \
--bind-address=192.168.31.63 \
--secure-port=6443 \
--advertise-address=192.168.31.63 \
--allow-privileged=true \
--service-cluster-ip-range=10.0.0.0/24 \
--enable-admission-plugins=NamespaceLifecycle,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota,NodeRestriction \
--authorization-mode=RBAC,Node \
--enable-bootstrap-token-auth \
--token-auth-file=/opt/kubernetes/cfg/token.csv \
--service-node-port-range=30000-50000 \
--tls-cert-file=/opt/kubernetes/ssl/server.pem  \
--tls-private-key-file=/opt/kubernetes/ssl/server-key.pem \
--client-ca-file=/opt/kubernetes/ssl/ca.pem \
--service-account-key-file=/opt/kubernetes/ssl/ca-key.pem \
--etcd-cafile=/opt/etcd/ssl/ca.pem \
--etcd-certfile=/opt/etcd/ssl/server.pem \
--etcd-keyfile=/opt/etcd/ssl/server-key.pem"

配置好前面生成的證書，確保能連接etcd。

參數說明：

• --logtostderr 啟用日志
• ---v 日志等級
• --etcd-servers etcd集群地址
• --bind-address 監聽地址
• --secure-port https安全端口
• --advertise-address 集群通告地址
• --allow-privileged 啟用授權
• --service-cluster-ip-range Service虛擬IP地址段
• --enable-admission-plugins 準入控制模塊
• --authorization-mode 認證授權，啟用RBAC授權和節點自管理
• --enable-bootstrap-token-auth 啟用TLS bootstrap功能，后面會講到
• --token-auth-file token文件
• --service-node-port-range Service Node類型默認分配端口范圍

systemd管理apiserver：

# cat /usr/lib/systemd/system/kube-apiserver.service 
[Unit]
Description=Kubernetes API Server
Documentation=https://github.com/kubernetes/kubernetes

[Service]
EnvironmentFile=-/opt/kubernetes/cfg/kube-apiserver
ExecStart=/opt/kubernetes/bin/kube-apiserver $KUBE_APISERVER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target

啟動：

# systemctl daemon-reload
# systemctl enable kube-apiserver
# systemctl restart kube-apiserver

4.3 部署scheduler組件

創建schduler配置文件：

# cat /opt/kubernetes/cfg/kube-scheduler 

KUBE_SCHEDULER_OPTS="--logtostderr=true \
--v=4 \
--master=127.0.0.1:8080 \
--leader-elect"

參數說明：

• --master 連接本地apiserver
• --leader-elect 當該組件啟動多個時，自動選舉（HA）

systemd管理schduler組件：

# cat /usr/lib/systemd/system/kube-scheduler.service 
[Unit]
Description=Kubernetes Scheduler
Documentation=https://github.com/kubernetes/kubernetes

[Service]
EnvironmentFile=-/opt/kubernetes/cfg/kube-scheduler
ExecStart=/opt/kubernetes/bin/kube-scheduler $KUBE_SCHEDULER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target

啟動：

# systemctl daemon-reload
# systemctl enable kube-scheduler
# systemctl restart kube-scheduler

4.4 部署controller-manager組件

創建controller-manager配置文件：

# cat /opt/kubernetes/cfg/kube-controller-manager 
KUBE_CONTROLLER_MANAGER_OPTS="--logtostderr=true \
--v=4 \
--master=127.0.0.1:8080 \
--leader-elect=true \
--address=127.0.0.1 \
--service-cluster-ip-range=10.0.0.0/24 \
--cluster-name=kubernetes \
--cluster-signing-cert-file=/opt/kubernetes/ssl/ca.pem \
--cluster-signing-key-file=/opt/kubernetes/ssl/ca-key.pem  \
--root-ca-file=/opt/kubernetes/ssl/ca.pem \
--service-account-private-key-file=/opt/kubernetes/ssl/ca-key.pem"

systemd管理controller-manager組件：

# cat /usr/lib/systemd/system/kube-controller-manager.service 
[Unit]
Description=Kubernetes Controller Manager
Documentation=https://github.com/kubernetes/kubernetes

[Service]
EnvironmentFile=-/opt/kubernetes/cfg/kube-controller-manager
ExecStart=/opt/kubernetes/bin/kube-controller-manager $KUBE_CONTROLLER_MANAGER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target

啟動：

# systemctl daemon-reload
# systemctl enable kube-controller-manager
# systemctl restart kube-controller-manager

所有組件都已經啟動成功，通過kubectl工具查看當前集群組件狀態：

# /opt/kubernetes/bin/kubectl get cs
NAME                 STATUS    MESSAGE             ERROR
scheduler            Healthy   ok                  
etcd-0               Healthy   {"health":"true"}   
etcd-2               Healthy   {"health":"true"}   
etcd-1               Healthy   {"health":"true"}   
controller-manager   Healthy   ok

如上輸出說明組件都正常。

5. 在Node節點部署組件

Master apiserver啟用TLS認證后，Node節點kubelet組件想要加入集群，必須使用CA簽發的有效證書才能與apiserver通信，當Node節點很多時，簽署證書是一件很繁瑣的事情，因此有了TLS Bootstrapping機制，kubelet會以一個低權限用戶自動向apiserver申請證書，kubelet的證書由apiserver動態簽署。

認證大致工作流程如圖所示：

5.1 將kubelet-bootstrap用戶綁定到系統集群角色

kubectl create clusterrolebinding kubelet-bootstrap \
  --clusterrole=system:node-bootstrapper \
  --user=kubelet-bootstrap

5.2 創建kubeconfig文件

在生成kubernetes證書的目錄下執行以下命令生成kubeconfig文件：

# 創建kubelet bootstrapping kubeconfig 
BOOTSTRAP_TOKEN=674c457d4dcf2eefe4920d7dbb6b0ddc
KUBE_APISERVER="https://192.168.31.63:6443"

# 設置集群參數
kubectl config set-cluster kubernetes \
  --certificate-authority=./ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=bootstrap.kubeconfig

# 設置客戶端認證參數
kubectl config set-credentials kubelet-bootstrap \
  --token=${BOOTSTRAP_TOKEN} \
  --kubeconfig=bootstrap.kubeconfig

# 設置上下文參數
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kubelet-bootstrap \
  --kubeconfig=bootstrap.kubeconfig

# 設置默認上下文
kubectl config use-context default --kubeconfig=bootstrap.kubeconfig

#----------------------

# 創建kube-proxy kubeconfig文件

kubectl config set-cluster kubernetes \
  --certificate-authority=./ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=kube-proxy.kubeconfig

kubectl config set-credentials kube-proxy \
  --client-certificate=./kube-proxy.pem \
  --client-key=./kube-proxy-key.pem \
  --embed-certs=true \
  --kubeconfig=kube-proxy.kubeconfig

kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-proxy \
  --kubeconfig=kube-proxy.kubeconfig

kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig

# ls
bootstrap.kubeconfig  kube-proxy.kubeconfig

將這兩個文件拷貝到Node節點/opt/kubernetes/cfg目錄下。

5.2 部署kubelet組件

將前面下載的二進制包中的kubelet和kube-proxy拷貝到/opt/kubernetes/bin目錄下。

創建kubelet配置文件：

# cat /opt/kubernetes/cfg/kubelet
KUBELET_OPTS="--logtostderr=true \
--v=4 \
--hostname-override=192.168.31.65 \
--kubeconfig=/opt/kubernetes/cfg/kubelet.kubeconfig \
--bootstrap-kubeconfig=/opt/kubernetes/cfg/bootstrap.kubeconfig \
--config=/opt/kubernetes/cfg/kubelet.config \
--cert-dir=/opt/kubernetes/ssl \
--pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0"

參數說明：

• --hostname-override 在集群中顯示的主機名
• --kubeconfig 指定kubeconfig文件位置，會自動生成
• --bootstrap-kubeconfig 指定剛才生成的bootstrap.kubeconfig文件
• --cert-dir 頒發證書存放位置
• --pod-infra-container-image 管理Pod網絡的鏡像

其中/opt/kubernetes/cfg/kubelet.config配置文件如下：

kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: 192.168.31.65
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS: ["10.0.0.2"]
clusterDomain: cluster.local.
failSwapOn: false
authentication:
  anonymous:
    enabled: true 

systemd管理kubelet組件：

# cat /usr/lib/systemd/system/kubelet.service 
[Unit]
Description=Kubernetes Kubelet
After=docker.service
Requires=docker.service

[Service]
EnvironmentFile=/opt/kubernetes/cfg/kubelet
ExecStart=/opt/kubernetes/bin/kubelet $KUBELET_OPTS
Restart=on-failure
KillMode=process

[Install]
WantedBy=multi-user.target

啟動：

# systemctl daemon-reload
# systemctl enable kubelet
# systemctl restart kubelet

在Master審批Node加入集群：

啟動后還沒加入到集群中，需要手動允許該節點才可以。
在Master節點查看請求簽名的Node：

# kubectl get csr
# kubectl certificate approve XXXXID
# kubectl get node

5.3 部署kube-proxy組件

創建kube-proxy配置文件：

# cat /opt/kubernetes/cfg/kube-proxy
KUBE_PROXY_OPTS="--logtostderr=true \
--v=4 \
--hostname-override=192.168.31.65 \
--cluster-cidr=10.0.0.0/24 \
--kubeconfig=/opt/kubernetes/cfg/kube-proxy.kubeconfig"

systemd管理kube-proxy組件：

# cat /usr/lib/systemd/system/kube-proxy.service 
[Unit]
Description=Kubernetes Proxy
After=network.target

[Service]
EnvironmentFile=-/opt/kubernetes/cfg/kube-proxy
ExecStart=/opt/kubernetes/bin/kube-proxy $KUBE_PROXY_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target

啟動：

# systemctl daemon-reload
# systemctl enable kube-proxy
# systemctl restart kube-proxy

Node2部署方式一樣。

6. 查看集群狀態

# kubectl get node
NAME             STATUS    ROLES     AGE       VERSION
192.168.31.65   Ready     <none>    1d       v1.12.0
192.168.31.66   Ready     <none>    1d       v1.12.0
# kubectl get cs
NAME                 STATUS    MESSAGE             ERROR
controller-manager   Healthy   ok                  
scheduler            Healthy   ok                  
etcd-2               Healthy   {"health":"true"}   
etcd-1               Healthy   {"health":"true"}   
etcd-0               Healthy   {"health":"true"}

7. 運行一個測試示例

創建一個Nginx Web，測試集群是否正常工作：

# kubectl run nginx --image=nginx --replicas=3
# kubectl expose deployment nginx --port=88 --target-port=80 --type=NodePort

查看Pod，Service：

# kubectl get pods
NAME                     READY     STATUS    RESTARTS   AGE
nginx-64f497f8fd-fjgt2   1/1       Running   3          1d
nginx-64f497f8fd-gmstq   1/1       Running   3          1d
nginx-64f497f8fd-q6wk9   1/1       Running   3          1d
# kubectl get svc
NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)                        AGE
kubernetes   ClusterIP   10.0.0.1     <none>        443/TCP                        28d
nginx        NodePort    10.0.0.175   <none>        88:38696/TCP                   28d

訪問集群中部署的Nginx，打開瀏覽器輸入：http://192.168.31.66:38696

免費視頻版：https://ke.qq.com/course/366778

小結

• 有問題先查日志，再谷歌
• 多思考，多梳理邏輯
• 配置文件較多，有很多字段你可能都不知道干啥，不要著急，隨著一步步使用，慢慢就熟悉了

若你在容器運維中，遇到容器方面的問題，可以給我微信↓。同樣，若發現有任何紕漏，還請隨時指正，相互學習，共同進步！