03 . 二進位制部署kubernetes1.18.4

簡介

目前生產部署kubernetes叢集主要兩種方式

kubeadm

Kubeadm是一個K8s部署工具，提供kubeadm init和kubeadm join，用於快速部署Kubernetes叢集。

二進位制包

從github下載發行版的二進位制包，手動部署每個元件，組成Kubernetes叢集。

Kubeadm降低部署門檻，但遮蔽了很多細節，遇到問題很難排查。如果想更容易可控，推薦使用二進位制包部署Kubernetes叢集，雖然手動部署麻煩點，期間可以學習很多工作原理，也利於後期維護。

二進位制部署K8s

List

CentOS7.3
cni-plugins-linux-amd64-v0.8.6.tgz
etcd-v3.4.9-linux-amd64.tar.gz
kube-flannel.yml
kubernetes-server-linux-amd64.tar.gz

角色	IP	元件
master	192.168.31.71	kube-apiserver，kube-controller-manager，kube-scheduler，etcd
Node1	192.168.31.74	kube-apiserver，kube-controller-manager，kube-scheduler
Node2	192.168.31.72	kubelet，kube-proxy，docker etcd

初始化環境

# 初始化
init_security() {
systemctl stop firewalld
systemctl disable firewalld &>/dev/null
setenforce 0
sed -i '/^SELINUX=/ s/enforcing/disabled/'  /etc/selinux/config
sed -i '/^GSSAPIAu/ s/yes/no/' /etc/ssh/sshd_config
sed -i '/^#UseDNS/ {s/^#//;s/yes/no/}' /etc/ssh/sshd_config
systemctl enable sshd crond &> /dev/null
rpm -e postfix --nodeps
echo -e "\033[32m [安全配置] ==> OK \033[0m"
}
init_security

init_yumsource() {
if [ ! -d /etc/yum.repos.d/backup ];then
    mkdir /etc/yum.repos.d/backup
fi
mv /etc/yum.repos.d/* /etc/yum.repos.d/backup 2>/dev/null
if ! ping -c2 www.baidu.com &>/dev/null    
then
    echo "您無法上外網，不能配置yum源"
    exit    
fi
    curl -o /etc/yum.repos.d/163.repo http://mirrors.163.com/.help/CentOS7-Base-163.repo &>/dev/null
    curl -o /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo &>/dev/null
    yum clean all
    timedatectl set-timezone Asia/Shanghai
    echo "nameserver 114.114.114.114" > /etc/resolv.conf
    echo "nameserver 8.8.8.8" >> /etc/resolv.conf
    chattr +i /etc/resolv.conf
    yum -y install ntpdate
    ntpdate -b  ntp1.aliyun.com        # 對時很重要
    echo -e "\033[32m [YUM　Source] ==> OK \033[0m"
}
init_yumsource

# 關掉swap分割槽
swapoff -a
# 如果想永久關掉swap分割槽，開啟如下檔案註釋掉swap哪一行即可.
sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab #永久

# 配置主機名解析
tail -3 /etc/hosts
192.168.0.121 master
192.168.0.123 node1
192.168.0.124 node2

# 將橋接的IPv4流量傳遞到iptables的鏈
cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system  # 生效


# 升級核心(非必須,只是效能更好)
wget https://cbs.centos.org/kojifiles/packages/kernel/4.9.220/37.el7/x86_64/kernel-4.9.220-37.el7.x86_64.rpm
  
rpm -ivh kernel-4.9.220-37.el7.x86_64.rpm
reboot

部署etcd叢集

Etcd 是一個分散式鍵值儲存系統，Kubernetes使用Etcd進行資料儲存，所以先準備一個Etcd資料庫，為解決Etcd單點故障，應採用叢集方式部署，這裡使用3臺組建叢集，可容忍1臺機器故障，當然，你也可以使用5臺組建叢集，可容忍2臺機器故障。

節點名稱	IP
etcd-1	192.168.31.71
etcd-2	192.168.31.72
etcd-3	192.168.31.73

注：為了節省機器，這裡與K8s節點機器複用。也可以獨立於k8s叢集之外部署，只要apiserver能連線到就行。

準備cfssl證照生成工具

cfssl是一個開源的證照管理工具，使用json檔案生成證照，相比openssl更方便使用。

找任意一臺伺服器操作，這裡用Master節點。

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

生成etcd證照

建立工作目錄

mkdir -p ~/TLS/{etcd,k8s}

cd TLS/etcd

自籤CA

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

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

生成證照

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

ls *pem
ca-key.pem  ca.pem

使用自籤CA簽發etcd https證照

建立證照申請檔案

cat > server-csr.json << EOF
{
    "CN": "etcd",
    "hosts": [
    "192.168.0.121",
    "192.168.0.123",
    "192.168.0.124"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "BeiJing",
            "ST": "BeiJing"
        }
    ]
}
EOF

注：上述檔案hosts欄位中IP為所有etcd節點的叢集內部通訊IP，一個都不能少！為了方便後期擴容可以多寫幾個預留的IP。

生成證照

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

ls server*pem
server-key.pem  server.pem

下載etcd二進位制檔案

wget https://github.com/etcd-io/etcd/releases/download/v3.4.9/etcd-v3.4.9-linux-amd64.tar.gz

建立工作目錄並解壓二進位制包

mkdir /opt/etcd/{bin,cfg,ssl} -p
tar zxvf etcd-v3.4.9-linux-amd64.tar.gz
mv etcd-v3.4.9-linux-amd64/{etcd,etcdctl} /opt/etcd/bin/

# 配置etcd
cat /opt/etcd/cfg/etcd.conf 
#[Member]
ETCD_NAME="etcd-1"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.0.121:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.0.121:2379"
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.0.121:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.0.121:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.0.121:2380,etcd-2=https://192.168.0.123:2380,etcd-3=https://192.168.0.124:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"

# ETCD_NAME：節點名稱，叢集中唯一
# ETCD_DATA_DIR：資料目錄
# ETCD_LISTEN_PEER_URLS：叢集通訊監聽地址
# ETCD_LISTEN_CLIENT_URLS：客戶端訪問監聽地址
# ETCD_INITIAL_ADVERTISE_PEER_URLS：叢集通告地址
# ETCD_ADVERTISE_CLIENT_URLS：客戶端通告地址
# ETCD_INITIAL_CLUSTER：叢集節點地址
# ETCD_INITIAL_CLUSTER_TOKEN：叢集Token
# ETCD_INITIAL_CLUSTER_STATE：加入叢集的當前狀態，new是新叢集，existing表示加入已有叢集

systemd管理etcd

cat > /usr/lib/systemd/system/etcd.service << EOF
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target
[Service]
Type=notify
EnvironmentFile=/opt/etcd/cfg/etcd.conf
ExecStart=/opt/etcd/bin/etcd \
--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 \
--logger=zap
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF

拷貝剛生成證照及生成的檔案拷貝到節點2,節點3

cp ~/TLS/etcd/ca*pem ~/TLS/etcd/server*pem /opt/etcd/ssl/

scp -r /opt/etcd/ node1:/opt/
scp -r /opt/etcd/ node2:/opt/
scp /usr/lib/systemd/system/etcd.service node1:/usr/lib/systemd/system/
scp /usr/lib/systemd/system/etcd.service node2:/usr/lib/systemd/system/

修改節點2和節點3etcd.conf配置檔案

node-1
cat /opt/etcd/cfg/etcd.conf 
#[Member]
ETCD_NAME="etcd-2"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.0.123:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.0.123:2379"
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.0.123:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.0.123:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.0.121:2380,etcd-2=https://192.168.0.123:2380,etcd-3=https://192.168.0.124:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"


# node-2
#[Member]
ETCD_NAME="etcd-3"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.0.124:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.0.124:2379"
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.0.124:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.0.124:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.0.121:2380,etcd-2=https://192.168.0.123:2380,etcd-3=https://192.168.0.124:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"

# 啟動服務並設定開機自啟
systemctl daemon-reload
systemctl start etcd
systemctl enable etcd

驗證etcd叢集狀態

 /opt/etcd/bin/etcdctl --cacert=/opt/etcd/ssl/ca.pem --cert=/opt/etcd/ssl/server.pem --key=/opt/etcd/ssl/server-key.pem --endpoints="https://192.168.0.121:2379,https://192.168.0.123:2379,https://192.168.0.124:2379" endpoint healthhttps://192.168.0.124:2379 is healthy: successfully committed proposal: took = 13.213712ms
https://192.168.0.121:2379 is healthy: successfully committed proposal: took = 12.907787ms
https://192.168.0.123:2379 is healthy: successfully committed proposal: took = 12.168703ms
        
# 如果輸出上面資訊，就說明叢集部署成功。如果有問題第一步先看日誌：/var/log/message 或 journalctl -u etcd

安裝docker

下載安裝docker

sudo yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
yum -y install docker-ce-19.03.9-3.el7

配置docker映象源

mkdir /etc/docker
cat > /etc/docker/daemon.json << EOF
{
  "registry-mirrors": ["https://b9pmyelo.mirror.aliyuncs.com"]
}
EOF

啟動並設定開機自啟

systemctl daemon-reload
systemctl start docker
systemctl enable docker

部署Master Node

生成kube-apiserver證照

1. 自簽證照頒發機構(CA)

cat > ca-config.json << EOF
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "kubernetes": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}
EOF
cat > ca-csr.json << EOF
{
    "CN": "kubernetes",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}
EOF

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

ls *pem
ca-key.pem  ca.pem

使用自籤CA簽發kube-apiserver https 證照

cat /root/TLS/k8s/server-csr.json 
{
    "CN": "kubernetes",
    "hosts": [
      "10.0.0.1",
      "127.0.0.1",
      "192.168.0.121",
      "192.168.0.123",
      "192.168.0.124",
      "192.168.0.125",
      "192.168.0.100",
      "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"
        }
    ]
}

# 上述檔案hosts欄位中IP為所有Master/LB/VIP IP，一個都不能少！為了方便後期擴容可以多寫幾個預留的IP。

# 生成證照
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes server-csr.json | cfssljson -bare server

ls server*pem
server-key.pem  server.pem

下載解壓二進位制包

wget https://dl.k8s.io/v1.18.4/kubernetes-server-linux-amd64.tar.gz
mkdir -p /opt/kubernetes/{bin,cfg,ssl,logs} 
tar zxvf kubernetes-server-linux-amd64.tar.gz
cd kubernetes/server/bin
cp kube-apiserver kube-scheduler kube-controller-manager /opt/kubernetes/bin
cp kubectl /usr/bin/

部署kube-apiserver

cat /opt/kubernetes/cfg/kube-apiserver.conf 
KUBE_APISERVER_OPTS="--logtostderr=false \
--v=2 \
--log-dir=/opt/kubernetes/logs \
--etcd-servers=https://192.168.0.121:2379,https://192.168.0.123:2379,https://192.168.0.124:2379 \
--bind-address=192.168.0.121 \
--secure-port=6443 \
--advertise-address=192.168.0.121 \
--allow-privileged=true \
--service-cluster-ip-range=10.0.0.0/24 \
--enable-admission-plugins=NamespaceLifecycle,LimitRanger,ServiceAccount,ResourceQuota,NodeRestriction \
--authorization-mode=RBAC,Node \
--enable-bootstrap-token-auth=true \
--token-auth-file=/opt/kubernetes/cfg/token.csv \
--service-node-port-range=30000-32767 \
--kubelet-client-certificate=/opt/kubernetes/ssl/server.pem \
--kubelet-client-key=/opt/kubernetes/ssl/server-key.pem \
--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 \
--audit-log-maxage=30 \
--audit-log-maxbackup=3 \
--audit-log-maxsize=100 \
--audit-log-path=/opt/kubernetes/logs/k8s-audit.log"


# –logtostderr：啟用日誌
# —v：日誌等級
# –log-dir：日誌目錄
# –etcd-servers：etcd叢集地址
# –bind-address：監聽地址
# –secure-port：https安全埠
# –advertise-address：叢集通告地址
# –allow-privileged：啟用授權
# –service-cluster-ip-range：Service虛擬IP地址段
# –enable-admission-plugins：准入控制模組
# –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機制
# –token-auth-file：bootstrap token檔案
# –service-node-port-range：Service nodeport型別預設分配埠範圍
# –kubelet-client-xxx：apiserver訪問kubelet客戶端證照
# –tls-xxx-file：apiserver https證照
# –etcd-xxxfile：連線Etcd叢集證照
# –audit-log-xxx：審計日誌

拷貝剛生成證照

cp ~/TLS/k8s/ca*pem ~/TLS/k8s/server*pem /opt/kubernetes/ssl/

啟用TLS Bootstrapping機制

TLS Bootstraping：Master apiserver啟用TLS認證後，Node節點kubelet和kube-proxy要與kube-apiserver進行通訊，必須使用CA簽發的有效證照才可以，當Node節點很多時，這種客戶端證照頒發需要大量工作，同樣也會增加叢集擴充套件複雜度。為了簡化流程，Kubernetes引入了TLS bootstraping機制來自動頒發客戶端證照，kubelet會以一個低許可權使用者自動向apiserver申請證照，kubelet的證照由apiserver動態簽署。所以強烈建議在Node上使用這種方式，目前主要用於kubelet，kube-proxy還是由我們統一頒發一個證照

TLS bootstraping 工作流程

建立上述配置檔案中token檔案

cat > /opt/kubernetes/cfg/token.csv << EOF
c47ffb939f5ca36231d9e3121a252940,kubelet-bootstrap,10001,"system:node-bootstrapper"
EOF

# 格式：token，使用者名稱，UID，使用者組

token也可自行生成替換

head -c 16 /dev/urandom | od -An -t x | tr -d ' '

systemd管理apiserver

cat > /usr/lib/systemd/system/kube-apiserver.service << EOF
[Unit]
Description=Kubernetes API Server
Documentation=https://github.com/kubernetes/kubernetes
[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-apiserver.conf
ExecStart=/opt/kubernetes/bin/kube-apiserver \$KUBE_APISERVER_OPTS
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF

啟動設定開機啟動

systemctl daemon-reload
systemctl start kube-apiserver
systemctl enable kube-apiserver

授權kubelet-bootstrap使用者允許請求證照

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

部署kube-controller-manager

建立配置檔案

cat /opt/kubernetes/cfg/kube-controller-manager.conf 
KUBE_CONTROLLER_MANAGER_OPTS="--logtostderr=false \
--v=2 \
--log-dir=/opt/kubernetes/logs \
--leader-elect=true \
--master=127.0.0.1:8080 \
--bind-address=127.0.0.1 \
--allocate-node-cidrs=true \
--cluster-cidr=10.244.0.0/16 \
--service-cluster-ip-range=10.0.0.0/24 \
--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 \
--experimental-cluster-signing-duration=87600h0m0s"

# –master：通過本地非安全本地埠8080連線apiserver。
# –leader-elect：當該元件啟動多個時，自動選舉（HA）
# –cluster-signing-cert-file/–cluster-signing-key-file：自動為kubelet頒發證照的CA，與apiserver保持一致

systemd管理controller-manager

cat > /usr/lib/systemd/system/kube-controller-manager.service << EOF
[Unit]
Description=Kubernetes Controller Manager
Documentation=https://github.com/kubernetes/kubernetes
[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-controller-manager.conf
ExecStart=/opt/kubernetes/bin/kube-controller-manager \$KUBE_CONTROLLER_MANAGER_OPTS
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF

啟動設定開機啟動

systemctl daemon-reload
systemctl start kube-controller-manager
systemctl enable kube-controller-manager

部署kube-scheduler

建立配置檔案

cat /opt/kubernetes/cfg/kube-scheduler.conf 
KUBE_SCHEDULER_OPTS="--logtostderr=false --v=2 --log-dir=/opt/kubernetes/logs --leader-elect --master=127.0.0.1:8080 --bind-address=127.0.0.1"

# –master：通過本地非安全本地埠8080連線apiserver。
# –leader-elect：當該元件啟動多個時，自動選舉（HA）

systemd管理scheduler

cat > /usr/lib/systemd/system/kube-scheduler.service << EOF
[Unit]
Description=Kubernetes Scheduler
Documentation=https://github.com/kubernetes/kubernetes
[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-scheduler.conf
ExecStart=/opt/kubernetes/bin/kube-scheduler \$KUBE_SCHEDULER_OPTS
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF

啟動並設定開機自啟動

systemctl daemon-reload
systemctl start kube-scheduler
systemctl enable kube-scheduler

檢視叢集狀態

# 所有元件都已經啟動成功，通過kubectl工具檢視當前叢集元件狀態：
kubectl get cs
NAME                 STATUS    MESSAGE             ERROR
scheduler            Healthy   ok                  
controller-manager   Healthy   ok                  
etcd-2               Healthy   {"health":"true"}   
etcd-1               Healthy   {"health":"true"}   
etcd-0               Healthy   {"health":"true"} 

部署worker node

下面還是在Master Node上操作，即同時作為Worker Node

建立工作目錄並拷貝二進位制檔案

在所有worker node建立工作目錄

mkdir -p /opt/kubernetes/{bin,cfg,ssl,logs} 

從master節點拷貝

cd kubernetes/server/bin
cp kubelet kube-proxy /opt/kubernetes/bin   # 本地拷貝,註釋這裡操作還是master節點,

部署kubelet

建立配置檔案

cat /opt/kubernetes/cfg/kubelet.conf 
KUBELET_OPTS="--logtostderr=false \
--v=2 \
--log-dir=/opt/kubernetes/logs \
--hostname-override=master \
--network-plugin=cni \
--kubeconfig=/opt/kubernetes/cfg/kubelet.kubeconfig \
--bootstrap-kubeconfig=/opt/kubernetes/cfg/bootstrap.kubeconfig \
--config=/opt/kubernetes/cfg/kubelet-config.yml \
--cert-dir=/opt/kubernetes/ssl \
--pod-infra-container-image=lizhenliang/pause-amd64:3.0"


# –hostname-override：顯示名稱，叢集中唯一
# –network-plugin：啟用CNI
# –kubeconfig：空路徑，會自動生成，後面用於連線apiserver
# –bootstrap-kubeconfig：首次啟動向apiserver申請證照
# –config：配置引數檔案
# –cert-dir：kubelet證照生成目錄
# –pod-infra-container-image：管理Pod網路容器的映象

配置引數檔案

cat > /opt/kubernetes/cfg/kubelet-config.yml << EOF
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: 0.0.0.0
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS:
- 10.0.0.2
clusterDomain: cluster.local 
failSwapOn: false
authentication:
  anonymous:
    enabled: false
  webhook:
    cacheTTL: 2m0s
    enabled: true
  x509:
    clientCAFile: /opt/kubernetes/ssl/ca.pem 
authorization:
  mode: Webhook
  webhook:
    cacheAuthorizedTTL: 5m0s
    cacheUnauthorizedTTL: 30s
evictionHard:
  imagefs.available: 15%
  memory.available: 100Mi
  nodefs.available: 10%
  nodefs.inodesFree: 5%
maxOpenFiles: 1000000
maxPods: 110
EOF

生成bootstrap.kubeconfig檔案

KUBE_APISERVER="https://192.168.0.121:6443" # apiserver IP:PORT

TOKEN="c47ffb939f5ca36231d9e3121a252940" # 與token.csv裡保持一致

# 生成 kubelet bootstrap kubeconfig 配置檔案
kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=bootstrap.kubeconfig
  
  
kubectl config set-credentials "kubelet-bootstrap" \
  --token=${TOKEN} \
  --kubeconfig=bootstrap.kubeconfig
  
  
kubectl config set-context default \
  --cluster=kubernetes \
  --user="kubelet-bootstrap" \
  --kubeconfig=bootstrap.kubeconfig
  
  
kubectl config use-context default --kubeconfig=bootstrap.kubeconfig

# 拷貝到配置檔案路徑
cp bootstrap.kubeconfig /opt/kubernetes/cfg

systemd管理kubelet

cat > /usr/lib/systemd/system/kubelet.service << EOF
[Unit]
Description=Kubernetes Kubelet
After=docker.service
[Service]
EnvironmentFile=/opt/kubernetes/cfg/kubelet.conf
ExecStart=/opt/kubernetes/bin/kubelet \$KUBELET_OPTS
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF

啟動並設定開機自啟

systemctl daemon-reload
systemctl start kubelet
systemctl enable kubelet

批准kubelet證照並加入叢集

# 檢視kubelet證照請求
kubectl get csr
NAME                                                   AGE    SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-uCEGPOIiDdlLODKts8J658HrFq9CZ--K6M4G7bjhk8A   6m3s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending

# 批准申請
kubectl certificate approve node-csr-uCEGPOIiDdlLODKts8J658HrFq9CZ--K6M4G7bjhk8A

# 檢視節點
kubectl get node
NAME     STATUS   ROLES    AGE    VERSION
master   Ready    <none>   123m   v1.18.4

# 由於網路外掛還沒有部署，節點會沒有準備就緒 NotReady

部署kube-proxy

建立配置檔案

cat > /opt/kubernetes/cfg/kube-proxy.conf << EOF
KUBE_PROXY_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--config=/opt/kubernetes/cfg/kube-proxy-config.yml"
EOF

建立引數檔案

cat > /opt/kubernetes/cfg/kube-proxy-config.yml << EOF
kind: KubeProxyConfiguration
apiVersion: kubeproxy.config.k8s.io/v1alpha1
bindAddress: 0.0.0.0
metricsBindAddress: 0.0.0.0:10249
clientConnection:
  kubeconfig: /opt/kubernetes/cfg/kube-proxy.kubeconfig
hostnameOverride: k8s-master
clusterCIDR: 10.0.0.0/24
EOF

生成kube-proxy.kubeconfig檔案

生成kube-proxy證照

# 切換工作目錄
cd TLS/k8s

# 建立證照請求檔案
cat > 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

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

ls kube-proxy*pem
kube-proxy-key.pem  kube-proxy.pem

生成kubeconfig檔案

KUBE_APISERVER="https://192.168.0.121:6443"

kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/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

# 拷貝配置檔案到指定路徑
cp kube-proxy.kubeconfig /opt/kubernetes/cfg/

systemd管理kube-proxy

cat > /usr/lib/systemd/system/kube-proxy.service << EOF
[Unit]
Description=Kubernetes Proxy
After=network.target
[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-proxy.conf
ExecStart=/opt/kubernetes/bin/kube-proxy \$KUBE_PROXY_OPTS
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF

啟動並設定開機啟動

systemctl daemon-reload
systemctl start kube-proxy
systemctl enable kube-proxy

部署CNI網路

準備二進位制檔案

wget https://github.com/containernetworking/plugins/releases/download/v0.8.6/cni-plugins-linux-amd64-v0.8.6.tgz
  
# 解壓二進位制檔案並移動到預設工作目錄
mkdir /opt/cni/bin
tar zxvf cni-plugins-linux-amd64-v0.8.6.tgz -C /opt/cni/bin

# 部署cni網路
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
sed -i -r "s#quay.io/coreos/flannel:.*-amd64#lizhenliang/flannel:v0.12.0-amd64#g" kube-flannel.yml

# 預設映象地址無法訪問，修改為docker hub映象倉庫。
kubectl apply -f kube-flannel.yml

kubectl get pods -n kube-system
NAME                          READY   STATUS    RESTARTS   AGE
kube-flannel-ds-amd64-2pc95   1/1     Running   0          72s

kubectl get node
NAME         STATUS   ROLES    AGE   VERSION
master   Ready    <none>   41m   v1.18.4
# 部署好網路外掛,Node準備就緒

授權apiserver訪問kubelet

cat > apiserver-to-kubelet-rbac.yaml << EOF
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  annotations:
    rbac.authorization.kubernetes.io/autoupdate: "true"
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
  name: system:kube-apiserver-to-kubelet
rules:
  - apiGroups:
      - ""
    resources:
      - nodes/proxy
      - nodes/stats
      - nodes/log
      - nodes/spec
      - nodes/metrics
      - pods/log
    verbs:
      - "*"
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: system:kube-apiserver
  namespace: ""
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:kube-apiserver-to-kubelet
subjects:
  - apiGroup: rbac.authorization.k8s.io
    kind: User
    name: kubernetes
EOF

kubectl apply -f apiserver-to-kubelet-rbac.yaml

新增加Worker Node

拷貝已部署好的Node相關檔案到新節點

scp -r /opt/kubernetes/ node1:/opt/
scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service node1:/usr/lib/systemd/system

scp -r /opt/cni/ node1:/opt/
scp /opt/kubernetes/ssl/ca.pem node1:/opt/kubernetes/ssl

刪除kubelet證照和kubeconfig檔案

rm -f /opt/kubernetes/cfg/kubelet.kubeconfig 
rm -f /opt/kubernetes/ssl/kubelet*

# 這幾個檔案是證照申請審批後自動生成的，每個Node不同，必須刪除重新生成。

修改主機名並設定開機自啟動

vi /opt/kubernetes/cfg/kubelet.conf
--hostname-override=node1

vi /opt/kubernetes/cfg/kube-proxy-config.yml
hostnameOverride: node1

# 啟動並設定開機啟動
systemctl daemon-reload
systemctl start kubelet
systemctl enable kubelet
systemctl start kube-proxy
systemctl enable kube-proxy

再master上批准Node kubelet證照申請

kubectl get csr
NAME                                                   AGE   SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-4zTjsaVSrhuyhIGqsefxzVoZDCNKei-aE2jyTP81Uro   89s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending

kubectl certificate approve node-csr-4zTjsaVSrhuyhIGqsefxzVoZDCNKei-aE2jyTP81Uro

kubectl get node
NAME     STATUS   ROLES    AGE    VERSION
master   Ready    <none>   138m   v1.18.4
node1    Ready    <none>   120m   v1.18.4
node2    Ready    <none>   112m   v1.18.4

部署Dashboard

下載dashboard.yaml檔案

wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta8/aio/deploy/recommended.yaml

修改yaml配置檔案使其埠暴露外部訪問

wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta8/aio/deploy/recommended.yaml
  
# 預設Dashboard只能叢集內部訪問，修改Service為NodePort型別，暴露到外部：

vi recommended.yaml
kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
spec:
  ports:
    - port: 443
      targetPort: 8443
      nodePort: 30001  # 修改這裡
  type: NodePort   # 修改這裡
  selector:
    k8s-app: kubernetes-dashboard

kubectl apply -f recommended.yaml

kubectl get pods,svc -n kubernetes-dashboard
NAME                                             READY   STATUS    RESTARTS   AGE
pod/dashboard-metrics-scraper-694557449d-69x7g   1/1     Running   0          111m
pod/kubernetes-dashboard-9774cc786-kwgkt         1/1     Running   0          111m

NAME                                TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)         AGE
service/dashboard-metrics-scraper   ClusterIP   10.0.0.3     <none>        8000/TCP        111m
service/kubernetes-dashboard        NodePort    10.0.0.122   <none>        443:30001/TCP   111m

建立service account並繫結預設cluster-admin管理員叢集角色

kubectl create serviceaccount dashboard-admin -n kube-system
kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk '/dashboard-admin/{print $1}')

# 接下來訪問https://node ip:30001
# 然後將上面過濾出來的token複製上面即可訪問dashboard

# 我們可以部署個Nginx測試下叢集可用性
kubectl run --generator=run-pod/v1 nginx-test2 --image=daocloud.io/library/nginx --port=80 --replicas=1

kubectl get pods -o wide
kubectl get pods -o wide
NAME          READY   STATUS    RESTARTS   AGE   IP           NODE    NOMINATED NODE   READINESS GATES
nginx-test2   1/1     Running   0          89m   10.244.2.2   node2   <none>           <none>

# 我們去相應的節點訪問指定IP即可訪問
[root@node1 ~]# curl -I -s  10.244.2.2 |grep 200
HTTP/1.1 200 OK

部署CoreDNS

CoreDNS用於叢集內部Service名稱解析

kubectl apply -f coredns.yaml 
serviceaccount/coredns created
clusterrole.rbac.authorization.k8s.io/system:coredns created
clusterrolebinding.rbac.authorization.k8s.io/system:coredns 
configmap/coredns created
deployment.apps/coredns created

DNS解析測試

kubectl run -it --rm dns-test --image=busybox:1.28.4 sh
If you don't see a command prompt, try pressing enter.
/ # nslookup kubernetes
Server:    10.0.0.2
Address 1: 10.0.0.2 kube-dns.kube-system.svc.cluster.local

Name:      kubernetes
Address 1: 10.0.0.1 kubernetes.default.svc.cluster.local

此篇文章借鑑於公眾號DevOps技術棧 ，作者阿良