1. 程式人生 > >Kubernetes二進制方式v1.13.2生產環境的安裝與配置(HTTPS+RBAC) ?

Kubernetes二進制方式v1.13.2生產環境的安裝與配置(HTTPS+RBAC) ?

googl modify 目前 ffi 通告 exe ppr firewalld 前臺

Kubernetes二進制方式v1.13.2生產環境的安裝與配置(HTTPS+RBAC)

一 背景

由於眾所周知的原因,在國內無法直接訪問Google的服務。二進制包由於其下載方便、靈活定制而深受廣大kubernetes使用者喜愛,成為企業部署生產環境比較流行的方式之一,Kubernetes v1.13.2是目前的最新版本。安裝部署過程可能比較復雜、繁瑣,因此在安裝過程中盡可能將操作步驟腳本話。文中涉及到的腳本已經通過本人測試。

二 環境及架構圖

2.1 軟件環境

OS(最小化安裝版):

cat /etc/centos-release
CentOS Linux release 7.6.1810 (Core)

Docker Engine:

docker version
Client:
 Version:           18.06.0-ce
 API version:       1.38
 Go version:        go1.10.3
 Git commit:        0ffa825
 Built:             Wed Jul 18 19:08:18 2018
 OS/Arch:           linux/amd64
 Experimental:      false
Server:
 Engine:
  Version:          18.06.0-ce
  API version:      1.38 (minimum version 1.12)
  Go version:       go1.10.3
  Git commit:       0ffa825
  Built:            Wed Jul 18 19:10:42 2018
  OS/Arch:          linux/amd64
  Experimental:     false

Kubenetes:

kubectl version
Client Version: version.Info{Major:"1", Minor:"13", GitVersion:"v1.13.2", GitCommit:"cff46ab41ff0bb44d8584413b598ad8360ec1def", GitTreeState:"clean", BuildDate:"2019-01-10T23:35:51Z", GoVersion:"go1.11.4", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"13", GitVersion:"v1.13.2", GitCommit:"cff46ab41ff0bb44d8584413b598ad8360ec1def", GitTreeState:"clean", BuildDate:"2019-01-10T23:28:14Z", GoVersion:"go1.11.4", Compiler:"gc", Platform:"linux/amd64"}

ETCD:

etcd --version
etcd Version: 3.3.11
Git SHA: 2cf9e51d2
Go Version: go1.10.7
Go OS/Arch: linux/amd64

Flannel:

flanneld -version
v0.11.0

2.2 服務器規劃

IP 主機名(Hostname) 角色(Role) 組件(Component)
172.31.2.11 gysl-master Master&Node kube-apiserverkube-controller-managerkube-scheduleretcd,(kubectl),kubelet,kube-proxy,docker,flannel
172.31.2.12 gysl-node1 Node kubelet,kube-proxy,docker,flannel,etcd
172.31.2.13 gysl-node2 Node kubelet,kube-proxy,docker,flannel,etcd

註:加粗部分是Master節點必須安裝的組件,etcd可以部署在其他節點,也可以部署在Master節點,kubectl是管理kubernetes的命令行工具。其余部分是Node節點必選組件。

2.3 節點或組件功能簡介

Master節點:
Master節點上面主要由四個模塊組成,apiserver,schedule,controller-manager,etcd。

apiserver: 負責對外提供RESTful的kubernetes API 的服務,它是系統管理指令的統一接口,任何對資源的增刪該查都要交給apiserver處理後再交給etcd。kubectl(kubernetes提供的客戶端工具,該工具內部是對kubernetes API的調用)是直接和apiserver交互的。

schedule: 負責調度Pod到合適的Node上,如果把scheduler看成一個黑匣子,那麽它的輸入是pod和由多個Node組成的列表,輸出是Pod和一個Node的綁定。kubernetes目前提供了調度算法,同樣也保留了接口。用戶根據自己的需求定義自己的調度算法。

controller-manager: 如果apiserver做的是前臺的工作的話,那麽controller-manager就是負責後臺的。每一個資源都對應一個控制器。而control manager就是負責管理這些控制器的,比如我們通過APIServer創建了一個Pod,當這個Pod創建成功後,apiserver的任務就算完成了。

etcd:etcd是一個高可用的鍵值存儲系統,kubernetes使用它來存儲各個資源的狀態,從而實現了Restful的API。

Node節點:
每個Node節點主要由二個模塊組成:kublet, kube-proxy。

kube-proxy: 該模塊實現了kubernetes中的服務發現和反向代理功能。kube-proxy支持TCP和UDP連接轉發,默認基Round Robin算法將客戶端流量轉發到與service對應的一組後端pod。服務發現方面,kube-proxy使用etcd的watch機制監控集群中service和endpoint對象數據的動態變化,並且維護一個service到endpoint的映射關系,從而保證了後端pod的IP變化不會對訪問者造成影響,另外,kube-proxy還支持session affinity。

kublet:kublet是Master在每個Node節點上面的agent,是Node節點上面最重要的模塊,它負責維護和管理該Node上的所有容器,但是如果容器不是通過kubernetes創建的,它並不會管理。本質上,它負責使Pod的運行狀態與期望的狀態一致。

2.4 Kubernetes架構圖

技術分享圖片

2.5 Kubernetes工作流程圖

技術分享圖片

三 操作步驟

3.1 針對性初始化設置

在所有主機上執行腳本KubernetesInstall-01.sh,以Master節點為例。

[root@gysl-master ~]# sh KubernetesInstall-01.sh

腳本內容如下:

#!/bin/bash
# Initialize the machine. This needs to be executed on every machine.
# Add host domain name.
cat>>/etc/hosts<<EOF
172.31.2.11 gysl-master
172.31.2.12 gysl-node1
172.31.2.13 gysl-node2
EOF
# Modify related kernel parameters.
cat>/etc/sysctl.d/kubernetes.conf<<EOF
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl -p /etc/sysctl.d/kubernetes.conf>&/dev/null
# Turn off and disable the firewalld.
systemctl stop firewalld
systemctl disable firewalld
# Disable the SELinux.
sed -i.bak ‘s/=enforcing/=disabled/‘ /etc/selinux/config
# Disable the swap .
sed -i.bak ‘s/^.*swap/#&/g‘ /etc/fstab
# Reboot the machine.
reboot

3.2 安裝Docker Engine並設置

在所有主機上執行腳本KubernetesInstall-02.sh,以Master節點為例。

[root@gysl-master ~]# sh KubernetesInstall-02.sh

腳本內容如下:

#!/bin/bash
# Install the Docker engine. This needs to be executed on every machine.
curl http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -o /etc/yum.repos.d/docker-ce.repo>&/dev/null
if [ $? -eq 0 ] ;
    then
        yum remove docker                       docker-client                       docker-client-latest                       docker-common                       docker-latest                       docker-latest-logrotate                       docker-logrotate                       docker-selinux                       docker-engine-selinux                       docker-engine>&/dev/null
        yum list docker-ce --showduplicates|grep "^doc"|sort -r
        yum -y install docker-ce-18.06.0.ce-3.el7
        rm -f /etc/yum.repos.d/docker-ce.repo
        systemctl enable docker && systemctl start docker && systemctl status docker
    else
        echo "Install failed! Please try again! ";
        exit 110
fi

註意:以上步驟需要在每一個節點上執行。如果啟用了swap,那麽是需要禁用的(腳本KubernetesInstall-01.sh已有涉及),具體可以通過 free 命令查看詳情。另外,還需要關註各個節點上的時間同步情況。

3.3 下載相關二進制包

在Master執行腳本KubernetesInstall-03.sh即可進行下載。

[root@gysl-master ~]# sh KubernetesInstall-03.sh

腳本內容如下:

#!/bin/bash
# Download relevant softwares. Please verify sha512 yourself.
while true;
    do
        echo "Downloading, please wait a moment." &&        curl -L -C - -O https://dl.k8s.io/v1.13.2/kubernetes-server-linux-amd64.tar.gz &&         curl -L -C - -O https://github.com/etcd-io/etcd/releases/download/v3.2.26/etcd-v3.2.26-linux-amd64.tar.gz &&         curl -L -C - -O https://pkg.cfssl.org/R1.2/cfssl_linux-amd64 &&         curl -L -C - -O https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64 &&         curl -L -C - -O https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64         curl -L -C - -O https://github.com/coreos/flannel/releases/download/v0.11.0/flannel-v0.11.0-linux-amd64.tar.gz
        if [ $? -eq 0 ];
            then
                echo "Congratulations! All software packages have been downloaded."
                break
        fi
    done

kubernetes-server-linux-amd64.tar.gz包括了kubernetes的主要組件,無需下載其他包。etcd-v3.2.26-linux-amd64.tar.gz是部署etcd需要用到的包。其余的是cfssl相關的軟件,暫不深究。網絡原因,只能寫腳本來下載了,這個過程可能需要一會兒。

3.4 部署etcd集群

3.4.1 創建CA證書

在Master執行腳本KubernetesInstall-04.sh。

[root@gysl-master ~]# sh KubernetesInstall-04.sh
2019/01/28 16:29:47 [INFO] generating a new CA key and certificate from CSR
2019/01/28 16:29:47 [INFO] generate received request
2019/01/28 16:29:47 [INFO] received CSR
2019/01/28 16:29:47 [INFO] generating key: rsa-2048
2019/01/28 16:29:47 [INFO] encoded CSR
2019/01/28 16:29:47 [INFO] signed certificate with serial number 368034386524991671795323408390048460617296625670
2019/01/28 16:29:47 [INFO] generate received request
2019/01/28 16:29:47 [INFO] received CSR
2019/01/28 16:29:47 [INFO] generating key: rsa-2048
2019/01/28 16:29:48 [INFO] encoded CSR
2019/01/28 16:29:48 [INFO] signed certificate with serial number 714486490152688826461700674622674548864494534798
2019/01/28 16:29:48 [WARNING] This certificate lacks a "hosts" field. This makes it unsuitable for
websites. For more information see the Baseline Requirements for the Issuance and Management
of Publicly-Trusted Certificates, v.1.1.6, from the CA/Browser Forum (https://cabforum.org);
specifically, section 10.2.3 ("Information Requirements").
/etc/etcd/ssl/ca-key.pem  /etc/etcd/ssl/ca.pem  /etc/etcd/ssl/server-key.pem  /etc/etcd/ssl/server.pem

腳本內容如下:

#!/bin/bash
mv cfssl* /usr/local/bin/
chmod +x /usr/local/bin/cfssl*
ETCD_SSL=/etc/etcd/ssl
mkdir -p $ETCD_SSL
# Create some CA certificates for etcd cluster.
cat<<EOF>$ETCD_SSL/ca-config.json
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "www": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}
EOF
cat<<EOF>$ETCD_SSL/ca-csr.json
{
    "CN": "etcd CA",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing"
        }
    ]
}
EOF
cat<<EOF>$ETCD_SSL/server-csr.json
{
    "CN": "etcd",
    "hosts": [
    "172.31.2.11",
    "172.31.2.12",
    "172.31.2.13"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing"
        }
    ]
}
EOF
cd $ETCD_SSL
cfssl_linux-amd64 gencert -initca ca-csr.json | cfssljson_linux-amd64 -bare ca -
cfssl_linux-amd64 gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=www server-csr.json | cfssljson_linux-amd64 -bare server
cd ~
# ca-key.pem  ca.pem  server-key.pem  server.pem
ls $ETCD_SSL/*.pem

3.4.2 配置etcd服務

3.4.2.1 在Master節點上進行配置

在Master執行腳本KubernetesInstall-05.sh。

[root@gysl-master ~]# sh KubernetesInstall-05.sh

腳本內容如下:

#!/bin/bash
# Deploy and configurate etcd service on the master node.
ETCD_CONF=/etc/etcd/etcd.conf
ETCD_SSL=/etc/etcd/ssl
ETCD_SERVICE=/usr/lib/systemd/system/etcd.service
tar -xzf etcd-v3.3.11-linux-amd64.tar.gz
cp -p etcd-v3.3.11-linux-amd64/etc* /usr/local/bin/

# The etcd configuration file. 
cat>$ETCD_CONF<<EOF
#[Member]
ETCD_NAME="etcd-01"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://172.31.2.11:2380"
ETCD_LISTEN_CLIENT_URLS="https://172.31.2.11:2379"

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://172.31.2.11:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://172.31.2.11:2379"
ETCD_INITIAL_CLUSTER="etcd-01=https://172.31.2.11:2380,etcd-02=https://172.31.2.12:2380,etcd-03=https://172.31.2.13:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF

# The etcd servcie configuration file.
cat>$ETCD_SERVICE<<EOF
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target

[Service]
Type=notify
EnvironmentFile=$ETCD_CONF
ExecStart=/usr/local/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=/etc/etcd/ssl/server.pem --key-file=/etc/etcd/ssl/server-key.pem --peer-cert-file=/etc/etcd/ssl/server.pem --peer-key-file=/etc/etcd/ssl/server-key.pem --trusted-ca-file=/etc/etcd/ssl/ca.pem --peer-trusted-ca-file=/etc/etcd/ssl/ca.pem
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable etcd.service --now
systemctl status etcd
3.4.2.2 在Node1節點上進行配置

在Node1執行腳本KubernetesInstall-06.sh。

[root@gysl-master ~]# sh KubernetesInstall-06.sh

腳本內容如下:

#!/bin/bash
# Deploy etcd on the node1.
ETCD_SSL=/etc/etcd/ssl
mkdir -p $ETCD_SSL
scp gysl-master:~/etcd-v3.3.11-linux-amd64.tar.gz .
scp gysl-master:$ETCD_SSL/{ca*pem,server*pem} $ETCD_SSL/
scp gysl-master:/etc/etcd/etcd.conf /etc/etcd/
scp gysl-master:/usr/lib/systemd/system/etcd.service /usr/lib/systemd/system/
tar -xvzf etcd-v3.3.11-linux-amd64.tar.gz
mv ~/etcd-v3.3.11-linux-amd64/etcd* /usr/local/bin/
sed -i ‘/ETCD_NAME/{s/etcd-01/etcd-02/g}‘ /etc/etcd/etcd.conf
sed -i ‘/ETCD_LISTEN_PEER_URLS/{s/2.11/2.12/g}‘ /etc/etcd/etcd.conf
sed -i ‘/ETCD_LISTEN_CLIENT_URLS/{s/2.11/2.12/g}‘ /etc/etcd/etcd.conf
sed -i ‘/ETCD_INITIAL_ADVERTISE_PEER_URLS/{s/2.11/2.12/g}‘ /etc/etcd/etcd.conf
sed -i ‘/ETCD_ADVERTISE_CLIENT_URLS/{s/2.11/2.12/g}‘ /etc/etcd/etcd.conf
rm -rf ~/etcd-v3.3.11-linux-amd64*
systemctl daemon-reload
systemctl enable etcd.service --now
systemctl status etcd
3.4.2.3 在Node2節點上進行配置

在Node2執行腳本KubernetesInstall-07.sh。

[root@gysl-master ~]# sh KubernetesInstall-07.sh

腳本內容如下:

#!/bin/bash
# Deploy etcd on the node2.
ETCD_SSL=/etc/etcd/ssl
mkdir -p $ETCD_SSL
scp gysl-master:~/etcd-v3.3.11-linux-amd64.tar.gz .
scp gysl-master:$ETCD_SSL/{ca*pem,server*pem} $ETCD_SSL/
scp gysl-master:/etc/etcd/etcd.conf /etc/etcd/
scp gysl-master:/usr/lib/systemd/system/etcd.service /usr/lib/systemd/system/
tar -xvzf etcd-v3.3.11-linux-amd64.tar.gz
mv ~/etcd-v3.3.11-linux-amd64/etcd* /usr/local/bin/
sed -i ‘/ETCD_NAME/{s/etcd-01/etcd-03/g}‘ /etc/etcd/etcd.conf
sed -i ‘/ETCD_LISTEN_PEER_URLS/{s/2.11/2.13/g}‘ /etc/etcd/etcd.conf
sed -i ‘/ETCD_LISTEN_CLIENT_URLS/{s/2.11/2.13/g}‘ /etc/etcd/etcd.conf
sed -i ‘/ETCD_INITIAL_ADVERTISE_PEER_URLS/{s/2.11/2.13/g}‘ /etc/etcd/etcd.conf
sed -i ‘/ETCD_ADVERTISE_CLIENT_URLS/{s/2.11/2.13/g}‘ /etc/etcd/etcd.conf
rm -rf ~/etcd-v3.3.11-linux-amd64*
systemctl daemon-reload
systemctl enable etcd.service --now
systemctl status etcd

幾個節點上的安裝過程大同小異,唯一不同的是etcd配置文件中的服務器IP要寫當前節點的IP。主要參數:

  • 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。

3.4.3 驗證etcd集群是否部署成功

執行以下命令:

[root@gysl-master ~]# etcdctl --ca-file=/etc/etcd/ssl/ca.pem --cert-file=/etc/etcd/ssl/server.pem --key-file=/etc/etcd/ssl/server-key.pem --endpoints="https://172.31.2.11:2379,https://172.31.2.12:2379,https://172.31.2.13:2379" cluster-health
member 82184ce461853bed is healthy: got healthy result from https://172.31.2.12:2379
member d85d48cef1ccfeaf is healthy: got healthy result from https://172.31.2.13:2379
member fe6e7c664377ad3b is healthy: got healthy result from https://172.31.2.11:2379
cluster is healthy

"cluster is healthy"說明etcd集群部署成功!如果存在問題,那麽首先看日誌:/var/log/message 或 journalctl -u etcd,找到問題,逐一解決。命令看起來不是那麽直觀,可以直接復制下面的命令來進行檢驗:

etcdctl --ca-file=/etc/etcd/ssl/ca.pem --cert-file=/etc/etcd/ssl/server.pem --key-file=/etc/etcd/ssl/server-key.pem --endpoints="https://172.31.2.11:2379,https://172.31.2.12:2379,https://172.31.2.13:2379" cluster-health

3.5 部署Flannel網絡

由於Flannel需要使用etcd存儲自身的一個子網信息,所以要保證能成功連接Etcd,寫入預定義子網段。寫入的Pod網段${CLUSTER_CIDR}必須是/16段地址,必須與kube-controller-manager的–-cluster-cidr參數值一致。一般情況下,在每一個Node節點都需要進行配置,執行腳本KubernetesInstall-08.sh。

[root@gysl-master ~]# sh KubernetesInstall-08.sh

腳本內容如下:

#!/bin/bash
KUBE_CONF=/etc/kubernetes
FLANNEL_CONF=$KUBE_CONF/flannel.conf
mkdir $KUBE_CONF
tar -xvzf flannel-v0.11.0-linux-amd64.tar.gz
mv {flanneld,mk-docker-opts.sh} /usr/local/bin/
# Check whether etcd cluster is healthy.
etcdctl --ca-file=/etc/etcd/ssl/ca.pem --cert-file=/etc/etcd/ssl/server.pem --key-file=/etc/etcd/ssl/server-key.pem --endpoints="https://172.31.2.11:2379,https://172.31.2.12:2379,https://172.31.2.13:2379" cluster-health

# Writing into a predetermined subnetwork.
cd /etc/etcd/ssl
etcdctl --ca-file=ca.pem --cert-file=server.pem --key-file=server-key.pem --endpoints="https://172.31.2.11:2379,https://172.31.2.12:2379,https://172.31.2.13:2379" set /coreos.com/network/config  ‘{ "Network": "172.17.0.0/16", "Backend": {"Type": "vxlan"}}‘
cd ~

# Configuration the flannel service.
cat>$FLANNEL_CONF<<EOF
FLANNEL_OPTIONS="--etcd-endpoints=https://172.31.2.11:2379,https://172.31.2.12:2379,https://172.31.2.13:2379 -etcd-cafile=/etc/etcd/ssl/ca.pem -etcd-certfile=/etc/etcd/ssl/server.pem -etcd-keyfile=/etc/etcd/ssl/server-key.pem"
EOF
cat>/usr/lib/systemd/system/flanneld.service<<EOF
[Unit]
Description=Flanneld overlay address etcd agent
After=network-online.target network.target
Before=docker.service

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

[Install]
WantedBy=multi-user.target
EOF

# Modify the docker service.
sed -i.bak -e ‘/ExecStart/i EnvironmentFile=\/run\/flannel\/subnet.env‘ -e ‘s/ExecStart=\/usr\/bin\/dockerd/ExecStart=\/usr\/bin\/dockerd $DOCKER_NETWORK_OPTIONS/g‘ /usr/lib/systemd/system/docker.service

# Start or restart related services.
systemctl daemon-reload
systemctl enable flanneld --now
systemctl restart docker
systemctl status flanneld
systemctl status docker
ip address show

在腳本執行之前需要把Flannel安裝包拷貝到用戶的HOME目錄。腳本執行完畢之後需要檢查各服務的狀態,確保docker0和flannel.1在同一網段。

3.6 部署Master節點

3.6.1 創建CA證書

這一步中創建了kube-apiserver和kube-proxy相關的CA證書,在Master節點執行腳本KubernetesInstall-09.sh。

[root@gysl-master ~]# sh KubernetesInstall-09.sh

腳本內容如下:

#!/bin/bash
# Deploy the master node.
KUBE_SSL=/etc/kubernetes/ssl
mkdir $KUBE_SSL

# Create CA.
cat>$KUBE_SSL/ca-config.json<<EOF
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "kubernetes": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}
EOF
cat>$KUBE_SSL/ca-csr.json<<EOF
{
    "CN": "kubernetes",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}
EOF
cat>$KUBE_SSL/server-csr.json<<EOF
{
    "CN": "kubernetes",
    "hosts": [
      "10.0.0.1",
      "127.0.0.1",
      "172.31.2.11",
      "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"
        }
    ]
}
EOF
cd $KUBE_SSL
cfssl_linux-amd64 gencert -initca ca-csr.json | cfssljson_linux-amd64 -bare ca -
cfssl_linux-amd64 gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes server-csr.json | cfssljson_linux-amd64 -bare server

# Create kube-proxy CA.
cat>$KUBE_SSL/kube-proxy-csr.json<<EOF
{
  "CN": "system:kube-proxy",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing",
      "ST": "BeiJing",
      "O": "k8s",
      "OU": "System"
    }
  ]
}
EOF
cfssl_linux-amd64 gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-proxy-csr.json | cfssljson_linux-amd64 -bare kube-proxy
ls *.pem
cd ~

執行完畢之後應該看到以下文件:
/etc/kubernetes/ssl/ca-key.pem /etc/kubernetes/ssl/kube-proxy-key.pem /etc/kubernetes/ssl/server-key.pem
/etc/kubernetes/ssl/ca.pem /etc/kubernetes/ssl/kube-proxy.pem /etc/kubernetes/ssl/server.pem

3.6.2 安裝配置kube-apiserver服務

將備好的安裝包解壓,並移動到相關目錄,進行相關配置,執行腳本KubernetesInstall-10.sh。

[root@gysl-master ~]# sh KubernetesInstall-10.sh

腳本內容如下:

#!/bin/bash
KUBE_ETC=/etc/kubernetes
KUBE_API_CONF=/etc/kubernetes/apiserver.conf
tar -xvzf kubernetes-server-linux-amd64.tar.gz
mv kubernetes/server/bin/{kube-apiserver,kube-scheduler,kube-controller-manager} /usr/local/bin/

# Create a token file.
cat>$KUBE_ETC/token.csv<<EOF
$(head -c 16 /dev/urandom | od -An -t x | tr -d ‘ ‘),kubelet-bootstrap,10001,"system:kubelet-bootstrap"
EOF

# Create a kube-apiserver configuration file.
cat >$KUBE_API_CONF<<EOF
KUBE_APISERVER_OPTS="--logtostderr=true --v=4 --etcd-servers=https://172.31.2.11:2379,https://172.31.2.12:2379,https://172.31.2.13:2379 --bind-address=172.31.2.11 --secure-port=6443 --advertise-address=172.31.2.11 --allow-privileged=true --service-cluster-ip-range=10.0.0.0/24 --enable-admission-plugins=NamespaceLifecycle,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota,NodeRestriction --authorization-mode=RBAC,Node --enable-bootstrap-token-auth --token-auth-file=$KUBE_ETC/token.csv --service-node-port-range=30000-50000 --tls-cert-file=$KUBE_ETC/ssl/server.pem  --tls-private-key-file=$KUBE_ETC/ssl/server-key.pem --client-ca-file=$KUBE_ETC/ssl/ca.pem --service-account-key-file=$KUBE_ETC/ssl/ca-key.pem --etcd-cafile=/etc/etcd/ssl/ca.pem --etcd-certfile=/etc/etcd/ssl/server.pem --etcd-keyfile=/etc/etcd/ssl/server-key.pem"
EOF

# Create the kube-apiserver service.
cat>/usr/lib/systemd/system/kube-apiserver.service<<EOF
[Unit]
Description=Kubernetes API Server
Documentation=https://github.com/kubernetes/kubernetes
After=etcd.service
Wants=etcd.service

[Service]
EnvironmentFile=-$KUBE_API_CONF
ExecStart=/usr/local/bin/kube-apiserver \$KUBE_APISERVER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kube-apiserver.service --now
systemctl status kube-apiserver.service

參數說明:

  • --logtostderr:啟用日誌。
  • --v:日誌等級。
  • --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。
  • --token-auth-file:token文件。
  • --service-node-port-range:Service Node類型默認分配端口範圍。

3.6.3 安裝配置kube-scheduler服務

之前已經將kube-scheduler相關的二進制文件移動到了相關目錄,直接執行腳本KubernetesInstall-11.sh。

[root@gysl-master ~]# sh KubernetesInstall-11.sh

腳本內容如下:

#!/bin/bash
# Deploy the scheduler service.
KUBE_ETC=/etc/kubernetes
KUBE_SCHEDULER_CONF=$KUBE_ETC/kube-scheduler.conf
cat>$KUBE_SCHEDULER_CONF<<EOF
KUBE_SCHEDULER_OPTS="--logtostderr=true --v=4 --master=127.0.0.1:8080 --leader-elect"
EOF

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

[Service]
EnvironmentFile=-$KUBE_SCHEDULER_CONF
ExecStart=/usr/local/bin/kube-scheduler \$KUBE_SCHEDULER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kube-scheduler.service --now
sleep 20
systemctl status kube-scheduler.service

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),被選為 leader的節點負責處理工作,其它節點為阻塞狀態。

3.6.4 安裝配置kube-controller服務

之前已經將kube-scheduler相關的二進制文件移動到了相關目錄,直接執行腳本KubernetesInstall-12.sh。

[root@gysl-master ~]# sh KubernetesInstall-12.sh

腳本內容如下:

#!/bin/bash
# Deploy the controller-manager service.
KUBE_CONTROLLER_CONF=/etc/kubernetes/kube-controller-manager.conf

cat>$KUBE_CONTROLLER_CONF<<EOF
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=/etc/kubernetes/ssl/ca.pem --cluster-signing-key-file=/etc/kubernetes/ssl/ca-key.pem  --root-ca-file=/etc/kubernetes/ssl/ca.pem --service-account-private-key-file=/etc/kubernetes/ssl/ca-key.pem"
EOF

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

[Service]
EnvironmentFile=-$KUBE_CONTROLLER_CONF
ExecStart=/usr/local/bin/kube-controller-manager \$KUBE_CONTROLLER_MANAGER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kube-controller-manager.service --now
sleep 20
systemctl status kube-controller-manager.service

3.6.5 查看集群狀態

直接執行腳本KubernetesInstall-13.sh。

[root@gysl-master ~]# sh KubernetesInstall-13.sh

腳本內容如下:

#!/bin/bash
# Check the service.
mv kubernetes/server/bin/kubectl /usr/local/bin/
kubectl get cs

如果部署成功的話,將看到如下結果:

[root@gysl-master ~]# kubectl get cs
NAME                 STATUS    MESSAGE             ERROR
controller-manager   Healthy   ok
scheduler            Healthy   ok
etcd-2               Healthy   {"health":"true"}
etcd-0               Healthy   {"health":"true"}
etcd-1               Healthy   {"health":"true"}

3.7 部署Node節點

3.7.1 創建bootstrap和kube-proxy的kubeconfig文件

Master apiserver啟用TLS認證後,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。在前面創建的token文件在這一步派上了用場,在Master節點上執行腳本KubernetesInstall-14.sh創建bootstrap.kubeconfig和kube-proxy.kubeconfig。

[root@gysl-master ~]# sh KubernetesInstall-14.sh

腳本內容如下:

#!/bin/bash
BOOTSTRAP_TOKEN=$(awk -F "," ‘{print $1}‘ /etc/kubernetes/token.csv)
KUBE_SSL=/etc/kubernetes/ssl/
KUBE_APISERVER="https://172.31.2.11:6443"

cd $KUBE_SSL
# Set cluster parameters.
kubectl config set-cluster kubernetes   --certificate-authority=./ca.pem   --embed-certs=true   --server=${KUBE_APISERVER}   --kubeconfig=bootstrap.kubeconfig

# Set client parameters.
kubectl config set-credentials kubelet-bootstrap   --token=${BOOTSTRAP_TOKEN}   --kubeconfig=bootstrap.kubeconfig

# Set context parameters. 
kubectl config set-context default   --cluster=kubernetes   --user=kubelet-bootstrap   --kubeconfig=bootstrap.kubeconfig

# Set context.
kubectl config use-context default --kubeconfig=bootstrap.kubeconfig

# Create kube-proxy kubeconfig file. 
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
cd ~

# Bind kubelet-bootstrap user to system cluster roles.
kubectl create clusterrolebinding kubelet-bootstrap   --clusterrole=system:node-bootstrapper   --user=kubelet-bootstrap

3.7.2 配置kube-proxy和kubelet服務

因為kubernetes-server-linux-amd64.tar.gz已經在Master節點的HOME目錄解壓,所以可以在各節點上執行腳本KubernetesInstall-15.sh。

[root@gysl-node1 ~]# sh KubernetesInstall-15.sh

腳本內容如下:

#!/bin/bash
KUBE_CONF=/etc/kubernetes
KUBE_SSL=$KUBE_CONF/ssl
IP=172.31.2.13
mkdir $KUBE_SSL
scp gysl-master:~/kubernetes/server/bin/{kube-proxy,kubelet} /usr/local/bin/
scp gysl-master:$KUBE_CONF/ssl/{bootstrap.kubeconfig,kube-proxy.kubeconfig} $KUBE_CONF
cat>$KUBE_CONF/kube-proxy.conf<<EOF
KUBE_PROXY_OPTS="--logtostderr=true --v=4 --hostname-override=$IP --cluster-cidr=10.0.0.0/24 --kubeconfig=$KUBE_CONF/kube-proxy.kubeconfig"
EOF
cat>/usr/lib/systemd/system/kube-proxy.service<<EOF
[Unit]
Description=Kubernetes Proxy
After=network.target

[Service]
EnvironmentFile=-$KUBE_CONF/kube-proxy.conf
ExecStart=/usr/local/bin/kube-proxy \$KUBE_PROXY_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF
systemctl daemon-reload
systemctl enable kube-proxy.service --now
sleep 20
systemctl status kube-proxy.service -l
cat>$KUBE_CONF/kubelet.yaml<<EOF
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: $IP
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS: ["10.0.0.2"]
clusterDomain: cluster.local.
failSwapOn: false
authentication:
  anonymous:
    enabled: true
EOF
cat>$KUBE_CONF/kubelet.conf<<EOF
KUBELET_OPTS="--logtostderr=true --v=4 --hostname-override=$IP --kubeconfig=$KUBE_CONF/kubelet.kubeconfig --bootstrap-kubeconfig=$KUBE_CONF/bootstrap.kubeconfig --config=$KUBE_CONF/kubelet.yaml --cert-dir=$KUBE_SSL --pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0"
EOF
cat>/usr/lib/systemd/system/kubelet.service<<EOF
[Unit]
Description=Kubernetes Kubelet
After=docker.service
Requires=docker.service

[Service]
EnvironmentFile=$KUBE_CONF/kubelet.conf
ExecStart=/usr/local/bin/kubelet \$KUBELET_OPTS
Restart=on-failure
KillMode=process

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kubelet.service --now
sleep 20
systemctl status kubelet.service -l

以上腳本有多少個Node節點就在相應的Node節點上執行多少次,每次執行只需修改IP的值即可。

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。

3.7.3 Approve kubelet CSR請求

可以手動或自動approve CSR請求。推薦使用自動的方式,因為從 v1.8 版本開始,可以自動輪轉approve csr後生成的證書。未approve之前如下:

[root@gysl-master ~]# kubectl get csr
NAME                                                   AGE   REQUESTOR           CONDITION
node-csr-FpTP2sCI0SiYDCxaIHa1SRukS_5u9BQN10BsTd6RU1Y   20m   kubelet-bootstrap   Pending
node-csr-YYfnPwAws2LxJzV-OgYjJ22zy_z9XQM8PT0MnqZN910   24m   kubelet-bootstrap   Pending

在Master節點上執行腳本KubernetesInstall-15.sh。

[root@gysl-master ~]# sh KubernetesInstall-15.sh
certificatesigningrequest.certificates.k8s.io/node-csr-FpTP2sCI0SiYDCxaIHa1SRukS_5u9BQN10BsTd6RU1Y approved
certificatesigningrequest.certificates.k8s.io/node-csr-YYfnPwAws2LxJzV-OgYjJ22zy_z9XQM8PT0MnqZN910 approved

腳本內容如下:

#!/bin/bash
CSRS=$(kubectl get csr | awk ‘{if(NR>1) print $1}‘)
for csr in $CSRS;
    do
        kubectl certificate approve $csr;
    done

3.7.4 查看集群狀態

[root@gysl-master ~]# 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"}
[root@gysl-master ~]# kubectl get node
NAME          STATUS   ROLES    AGE   VERSION
172.31.2.12   Ready    <none>   11m   v1.13.2
172.31.2.13   Ready    <none>   11m   v1.13.2

3.8 運行一個測試

[root@gysl-master ~]#  kubectl run nginx --image=nginx --replicas=3
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
deployment.apps/nginx created
[root@gysl-master ~]# kubectl expose deployment nginx --port=88 --target-port=80 --type=NodePort
service/nginx exposed
[root@gysl-master ~]# kubectl get pods
NAME                     READY   STATUS              RESTARTS   AGE
nginx-7cdbd8cdc9-7h946   0/1     ContainerCreating   0          33s
nginx-7cdbd8cdc9-vtkqf   0/1     ContainerCreating   0          33s
nginx-7cdbd8cdc9-wdjtj   0/1     ContainerCreating   0          33s
[root@gysl-master ~]# kubectl get svc
NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)        AGE
kubernetes   ClusterIP   10.0.0.1     <none>        443/TCP        8h
nginx        NodePort    10.0.0.2     <none>        88:46705/TCP   28s
[root@gysl-master ~]# kubectl get pods
NAME                     READY   STATUS    RESTARTS   AGE
nginx-7cdbd8cdc9-7h946   1/1     Running   0          2m4s
nginx-7cdbd8cdc9-vtkqf   1/1     Running   0          2m4s
nginx-7cdbd8cdc9-wdjtj   1/1     Running   0          2m4s
[root@gysl-node1 ~]# curl http://10.0.0.2:88
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
    body {
        width: 35em;
        margin: 0 auto;
        font-family: Tahoma, Verdana, Arial, sans-serif;
    }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>

<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>

<p><em>Thank you for using nginx.</em></p>
</body>
</html>

如果此時在瀏覽器輸入:<http://10.0.0.2:88> ,那麽將出現nginx的默認頁面。

3.9 在Master節點部署Node節點的相關組件

資源比較充裕的情況下,Master節點僅僅做為服務接口、調度、控制節點,必須部署的組件有:kube-apiserver、kube-controller-manager、kube-scheduler、kubectl、etcd。除此之外,一般還需要做HA等相關部署。如果Master節點資源比較充裕,有些實驗也要求至少有三個節點在運行,那麽也可以將Master節點部署設置為一般Node節點來使用。為此,直接執行腳本KubernetesInstall-17.sh。

[root@gysl-master ~]# KubernetesInstall-17.sh

腳本內容如下:

#!/bin/bash
KUBE_CONF=/etc/kubernetes
KUBE_SSL=$KUBE_CONF/ssl
IP=172.31.2.11
mkdir $KUBE_SSL
cp ~/kubernetes/server/bin/{kube-proxy,kubelet} /usr/local/bin/
cp $KUBE_CONF/ssl/{bootstrap.kubeconfig,kube-proxy.kubeconfig} $KUBE_CONF
cat>$KUBE_CONF/kube-proxy.conf<<EOF
KUBE_PROXY_OPTS="--logtostderr=true --v=4 --hostname-override=$IP --cluster-cidr=10.0.0.0/24 --kubeconfig=$KUBE_CONF/kube-proxy.kubeconfig"
EOF
cat>/usr/lib/systemd/system/kube-proxy.service<<EOF
[Unit]
Description=Kubernetes Proxy
After=network.target

[Service]
EnvironmentFile=-$KUBE_CONF/kube-proxy.conf
ExecStart=/usr/local/bin/kube-proxy \$KUBE_PROXY_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF
systemctl daemon-reload
systemctl enable kube-proxy.service --now
sleep 20
systemctl status kube-proxy.service -l
cat>$KUBE_CONF/kubelet.yaml<<EOF
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: $IP
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS: ["10.0.0.2"]
clusterDomain: cluster.local.
failSwapOn: false
authentication:
  anonymous:
    enabled: true
EOF
cat>$KUBE_CONF/kubelet.conf<<EOF
KUBELET_OPTS="--logtostderr=true --v=4 --hostname-override=$IP --kubeconfig=$KUBE_CONF/kubelet.kubeconfig --bootstrap-kubeconfig=$KUBE_CONF/bootstrap.kubeconfig --config=$KUBE_CONF/kubelet.yaml --cert-dir=$KUBE_SSL --pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0"
EOF
cat>/usr/lib/systemd/system/kubelet.service<<EOF
[Unit]
Description=Kubernetes Kubelet
After=docker.service
Requires=docker.service

[Service]
EnvironmentFile=$KUBE_CONF/kubelet.conf
ExecStart=/usr/local/bin/kubelet \$KUBELET_OPTS
Restart=on-failure
KillMode=process

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kubelet.service --now
sleep 20
systemctl status kubelet.service -l

kubectl certificate approve $(kubectl get csr | awk ‘{if(NR>1) print $1}‘)
kubectl get csr
kubectl label node 172.31.2.11  node-role.kubernetes.io/master=‘master‘
kubectl label node 172.31.2.12  node-role.kubernetes.io/node=‘node‘
kubectl label node 172.31.2.13  node-role.kubernetes.io/node=‘node‘
kubectl get nodes

部署成功之後,將出現以下內容:

NAME          STATUS   ROLES    AGE   VERSION
172.31.2.11   Ready    master   22m   v1.13.2
172.31.2.12   Ready    node     11h   v1.13.2
172.31.2.13   Ready    node     11h   v1.13.2

四 總結

4.1 Kubernetes的二進制安裝部署是一個比較復雜的過程,其中涉及到的步驟比較多,需要理解清楚各節點及組件之間的關系,逐步進行,每一個步驟成功了再進行下一步,切不可急躁。

4.2 在安裝部署的過程中,日誌及幫助信息是十分重要的,journalctl命令較為常用,--help也會起到柳暗花明又一村的效果。

4.3 把執行步驟腳本化,顯得清晰有效,在後續的工作、學習過程中要繼續保持。

4.4 由於時間倉促,安裝部署中的很多個性化配置並未配置,在後續過程中會根據實際使用情況進行完善。比如:每一個服務或組件並未將日誌單獨保存。

4.5 其他不盡如人意的地方正在完善。

4.6 文中的兩張圖片來源於互聯網,如有侵權,請聯系刪除。

五 參考資料

5.1 認證相關

5.2 證書相關

5.3 cfssl官方資料

5.4 Systemd相關資料

5.5 Kubernetes基本概念

5.6 本文涉及到的腳本及配置文件

Kubernetes二進制方式v1.13.2生產環境的安裝與配置(HTTPS+RBAC) ?