二进制部署高可用k8s集群

一 前置知识点

####1.1 环境准备

服务器要求

• 建议最小硬件配置:2核CPU、2G内存、30G硬盘

软件环境

软件 版本
操作系统 CentOS7.x_x64
容器引擎 Docker CE 19
Kubernetes Kubernetes v1.20

服务器整体规划

角色 IP 组件
k8s-matser1 172.21.51.71 kube-apiserver,kube-controller-manager,kube-scheduler,kubelet,kube-proxy,docker,etcd,nginx,keepalived
k8s-master2 172.21.51.74 kube-apiserver,kube-controller-manager,kube-scheduler,kubelet,kube-porxy,docker,nginx,Keepalived
k8s-node1 172.21.51.72 kubelet,kubeproxy,docker,etcd
k8s-node2 172.31.51.73 kubelet,kube-porxy,docker,etcd
负载均衡器 172.21.51.88(VIP)
也可以将etcd集群和负载均衡单独分离出来

单master架构图

二进制部署高可用k8s集群

单master服务器规划

角色 IP 组件
k8s-master 172.21.51.71 kube-apiserver,kube-controller-manager,kube-scheduler,etcd,docker
k8s-node1 172.21.51.72 kubelet,kube-proxy,docker,etcd
k8s-node2 172.21.51.73 kubelet,kube-proxy,docker,etcd

1.2操作系统初始化配置

# 关闭防火墙
systemctl stop firewalld 
systemctl disable firewalld 

# 关闭selinux 
sed -i 's/enforcing/disabled/' /etc/selinux/config  # 永久 
setenforce 0  # 临时 

# 关闭swap 
swapoff -a  # 临时 
sed -ri 's/.*swap.*/#&/' /etc/fstab    # 永久 
 
# 根据规划设置主机名 
hostnamectl set-hostname <hostname> 
 
# 在master添加hosts 
cat >> /etc/hosts << EOF 
172.21.51.71 k8s-master1 
172.21.51.72 k8s-node1 
172.21.51.73 k8s-node2 
EOF

# 将桥接的IPV4流量传递到iptables的链
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 
 

# 配置yum源
cd /etc/yum.repos.d/   && mkdir backup_$(date +%F)
mv ./*.repo  backup_
wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo
wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo
yum makecache && cd

# 安装常用
yum install -y ntpdate vim wget tree httpd-tools  lrzsz  net-tools bridge-utils  unzip telnet

# 时间同步 
ntpdate time.windows.com

# 关闭 networkmanager服务
systemctl enable NetworkManager
systemctl stop  NetworkManager

###二 部署ETCD集群

ETCD是一个分布式键值存储系统,kubernetes使用etcd进行数据存储,所以准备一个etcd数据库,为解决etcd单点故障,应采用集群方式部署,可容忍机器故障数量等于总数除以二减去一。

节点名称 IP
etcd-1 172.21.51.71
etcd-2 172.21.51.72
etcd-3 172.21.51.73

为了节省机器,这里与K8s节点机器复用。也可以独立于k8s集群之外部署,只要apiserver能连接到就行。

2.1准备cfssl证书生成工具

cfssl是一个开源的证书管理工具,使用JSON文件生成证书,相比openssl更方便使用。

在任意一台服务操作,这里了使用master节点部署。

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

2.2生成ETCD证书

1.自签证书颁发机构(CA)
# 准备目录
mkdir -p ~/TLS/{etcd,k8s}
cd ~/TLS/etcd

自签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

生成证书

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

# 如下:会生成ca.pem 和 ca-key.pem文件
[root@k8s-master1 etcd]# ll
total 8
-rw-r--r--. 1 root root 287 Aug 14 14:12 ca-config.json
-rw-r--r--. 1 root root 209 Aug 14 14:13 ca-csr.json
[root@k8s-master1 etcd]# cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
2021/08/14 14:13:17 [INFO] generating a new CA key and certificate from CSR
2021/08/14 14:13:17 [INFO] generate received request
2021/08/14 14:13:17 [INFO] received CSR
2021/08/14 14:13:17 [INFO] generating key: rsa-2048
2021/08/14 14:13:17 [INFO] encoded CSR
2021/08/14 14:13:17 [INFO] signed certificate with serial number 13042066667921354585937734212236512385297354843
[root@k8s-master1 etcd]# ls
ca-config.json  ca.csr  ca-csr.json  ca-key.pem  ca.pem

2.使用自签ca签发ETCD HTTPS证书*

创建证书申请文件

cat > server-csr.json << EOF
{
    "CN": "etcd",
    "hosts": [
    "172.21.51.71",
    "172.21.51.72",
    "172.21.51.73",
    "172.21.51.81",
    "172.21.51.82",
    "172.21.51.83"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "BeiJing",
            "ST": "BeiJing"
        }
    ]
}
EOF

注:上述文件hosts字段中IP为所有etcd节点的集群内部通信ip,只能多,不能少,为了方便后期扩容,可以多写几个预留IP。

生成证书

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

# 提示如下:会生成server.pem和server-key.pem文件
[root@k8s-master1 etcd]# cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=www server-csr.json | cfssljson -bare server
2021/08/14 14:31:33 [INFO] generate received request
2021/08/14 14:31:33 [INFO] received CSR
2021/08/14 14:31:33 [INFO] generating key: rsa-2048
2021/08/14 14:31:33 [INFO] encoded CSR
2021/08/14 14:31:33 [INFO] signed certificate with serial number 463187719751335716138642349093857998280805876080
2021/08/14 14:31:33 [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").
[root@k8s-master1 etcd]# echo $?
0
[root@k8s-master1 etcd]# ls
ca-config.json  ca.csr  ca-csr.json  ca-key.pem  ca.pem  server.csr  server-csr.json  server-key.pem  server.pem

2.3从GitHub下载二进制文件

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

2.4 部署etcd集群

以下在节点1上操作,为简化操作,待会将节点1生成的所有文件拷贝到节点2和节点3

1.创建挂载目录并解压二进制包
cd /opt/
mkdir -p /opt/etcd/{bin,cfg,ssl} -p
wget https://github.com/etcd-io/etcd/releases/download/v3.4.9/etcd-v3.4.9-linux-amd64.tar.gz
tar zxvf etcd-v3.4.9-linux-amd64.tar.gz
mv etcd-v3.4.9-linux-amd64/{etcd,etcdctl} /opt/etcd/bin/
2.创建etcd 配置文件
cat > /opt/etcd/cfg/etcd.conf << EOF
#[Member]
ETCD_NAME="etcd-1"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://172.21.51.71:2380"
ETCD_LISTEN_CLIENT_URLS="https://172.21.51.71:2379"

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://172.21.51.71:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://172.21.51.71:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://172.21.51.71:2380,etcd-2=https://172.21.51.72:2380,etcd-3=https://172.21.51.73:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF



参数解释:
ETCD_NAME= 节点名称,集群中必须唯一
ETCD_DATA_DIR= 数据目录
ETCD_LISTEN_PEER_URLS= 集群通信监听地址
ETCD_LISTEN_CLIENT_URLS= 客户端访问监听地址

ETCD_INITIAL_ADVERTISE_PEER_URLS= 集群通过地址
ETCD_ADVERTISE_CLIENT_URLS= 客户端通过地址
ETCD_INITIAL_CLUSTER= 集群各节点地址
ETCD_INITIAL_CLUSTER_TOKEN= 集群token
ETCD_INITIAL_CLUSTER_STATE= 加入集群的当前状态,new 是新机器,existing表示加入已有集群
3.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

4.拷贝刚才生成的证书

把刚才生成的证书拷贝到配置文件中的路径:

cp ~/TLS/etcd/ca*pem ~/TLS/etcd/server*pem /opt/etcd/ssl/
5.将上面节点1所有生成的文件拷贝的节点2和节点3
scp -r /opt/etcd/ root@172.21.51.72:/opt/
scp /usr/lib/systemd/system/etcd.service root@172.21.51.72:/usr/lib/systemd/system/
scp -r /opt/etcd/ root@172.21.51.73:/opt/
scp /usr/lib/systemd/system/etcd.service root@172.21.51.73:/usr/lib/systemd/system/

然后在节点2和节点3分别修改etcd.conf配置文件中的节点名称和当前服务器ip

vi /opt/etcd/cfg/etcd.conf
#[Member]
ETCD_NAME="etcd-2"   # 修改此处,节点2改为etcd-2,节点3改为etcd-3
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://172.21.51.72:2380"   # 修改此处为当前服务器IP
ETCD_LISTEN_CLIENT_URLS="https://172.21.51.72:2379" # 修改此处为当前服务器IP

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://172.21.51.72:2380" # 修改此处为当前服务器IP
ETCD_ADVERTISE_CLIENT_URLS="https://172.21.51.72:2379" # 修改此处为当前服务器IP
ETCD_INITIAL_CLUSTER="etcd-1=https://172.21.51.71:2380,etcd-2=https://172.21.51.72:2380,etcd-3=https://172.21.51.73:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"

6.最后启动etcd并设置开机启动
systemctl daemon-reload
systemctl start etcd
systemctl enable etcd
systemctl status etcd
查看启动日志
journalctl -fu etcd
7.查看集群状态
ETCDCTL_API=3 /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://172.21.51.71:2379,https://172.21.51.72:2379,https://172.21.51.73:2379" endpoint health --write-out=table

[root@k8s-master1 ~]# ETCDCTL=3 /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://172.21.51.71:2379,https://172.21.51.72:2379,https://172.21.51.73:2379" endpoint health --write-out=table
+---------------------------+--------+-------------+-------+
|         ENDPOINT          | HEALTH |    TOOK     | ERROR |
+---------------------------+--------+-------------+-------+
| https://172.21.51.71:2379 |   true |  8.964636ms |       |
| https://172.21.51.72:2379 |   true | 10.973473ms |       |
| https://172.21.51.73:2379 |   true | 11.852294ms |       |
+---------------------------+--------+-------------+-------+

如果输出上面信息,就说明集群部署成功。
如果有问题第一步先看日志:/var/log/message 或 journalctl -u etcd

三 安装docker

这里使用Docker作为容器引擎,也可以换成别的,例如containerd

下载地址:https://download.docker.com/linux/static/stable/x86_64/docker-19.03.9.tgz

以下在所有节点操作。这里采用二进制安装,用yum安装也一样。

3.1解压二进制包

wget https://download.docker.com/linux/static/stable/x86_64/docker-19.03.9.tgz
tar zxvf docker-19.03.9.tgz
mv docker/* /usr/bin

3.2 systemd管理docker

cat > /usr/lib/systemd/system/docker.service << EOF
[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target firewalld.service
Wants=network-online.target

[Service]
Type=notify
ExecStart=/usr/bin/dockerd
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
EOF

3.3 创建docker配置文件

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

# registry-mirrors 阿里云镜像加速器

3.4 启动并设置开机启动

systemctl daemon-reload
systemctl start docker
systemctl enable docker

四,部署master node

4.1 生成kube-apiserver证书

1.自签证书颁发机构(ca)
cd ~/TLS/k8s
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

生成证书

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

[root@k8s-master1 k8s]# cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
2021/08/14 23:48:47 [INFO] generating a new CA key and certificate from CSR
2021/08/14 23:48:47 [INFO] generate received request
2021/08/14 23:48:47 [INFO] received CSR
2021/08/14 23:48:47 [INFO] generating key: rsa-2048
2021/08/14 23:48:47 [INFO] encoded CSR
2021/08/14 23:48:47 [INFO] signed certificate with serial number 429434885767963696370191351654043895485854229933

会生成ca.pem 和ca-key.pem 文件
[root@k8s-master1 k8s]# ls
ca-config.json  ca.csr  ca-csr.json  ca-key.pem  ca.pem

2.使用自签ca签发kube-apiserver HTTPS证书

创建证书申请文件

cat > server-csr.json << EOF
{
    "CN": "kubernetes",
    "hosts": [
      "10.0.0.1",
      "127.0.0.1",
      "172.21.51.71",
      "172.21.51.72",
      "172.21.51.73",
      "172.21.51.74",
      "172.21.51.81",
      "172.21.51.82",
      "172.21.51.83",
      "172.21.51.84",
      "172.21.51.85",
      "172.21.51.88",
      "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

注:上述文件hosts字段中IP为所有Master/LB/VIP IP,一个都不能少!为了方便后期扩容可以多写几个预留的IP。

生成证书

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

4.2 从GitHub上下载二进制文件

https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.20.md

注:打开链接你会发现里面有很多包,下载一个server包就够了,包含了Master和Worker Node二进制文件。

wget https://dl.k8s.io/v1.20.9/kubernetes-server-linux-amd64.tar.gz

####4.3 解压二进制包

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

####4.4 部署kube-apiserver

1.创建配置文件
cat > /opt/kubernetes/cfg/kube-apiserver.conf << EOF
KUBE_APISERVER_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--etcd-servers=https://172.21.51.71:2379,https://172.21.51.72:2379,https://172.21.51.73:2379 \\
--bind-address=172.21.51.71 \\
--secure-port=6443 \\
--advertise-address=172.21.51.71 \\
--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 \\
--service-account-issuer=api \\
--service-account-signing-key-file=/opt/kubernetes/ssl/server-key.pem \\
--etcd-cafile=/opt/etcd/ssl/ca.pem \\
--etcd-certfile=/opt/etcd/ssl/server.pem \\
--etcd-keyfile=/opt/etcd/ssl/server-key.pem \\
--requestheader-client-ca-file=/opt/kubernetes/ssl/ca.pem \\
--proxy-client-cert-file=/opt/kubernetes/ssl/server.pem \\
--proxy-client-key-file=/opt/kubernetes/ssl/server-key.pem \\
--requestheader-allowed-names=kubernetes \\
--requestheader-extra-headers-prefix=X-Remote-Extra- \\
--requestheader-group-headers=X-Remote-Group \\
--requestheader-username-headers=X-Remote-User \\
--enable-aggregator-routing=true \\
--audit-log-maxage=30 \\
--audit-log-maxbackup=3 \\
--audit-log-maxsize=100 \\
--audit-log-path=/opt/kubernetes/logs/k8s-audit.log"
EOF

注:上面两个反斜杠 \ \ 第一个是转义符,第二个是换行符,使用转义符是为了 使用EOF保留换行符。

• --logtostderr:启用日志

• —v:日志等级,0-8

• --log-dir:日志目录

• --etcd-servers:etcd集群地址

• --bind-address:监听地址

• --secure-port:https安全端口

• --advertise-address:集群通告地址

• --allow-privileged:启用授权

• --service-cluster-ip-range:Service虚拟IP地址段

• --enable-admission-plugins:准入控制模块

• --authorization-mode:认证授权,启用RBAC授权和节点自管理

• --enable-bootstrap-token-auth:启用TLS bootstrap机制

• --token-auth-file:bootstrap token文件

• --service-node-port-range:Service nodeport类型默认分配端口范围

• --kubelet-client-xxx:apiserver访问kubelet客户端证书

• --tls-xxx-file:apiserver https证书

• 1.20版本必须加的参数:–service-account-issuer,–service-account-signing-key-file

• --etcd-xxxfile:连接Etcd集群证书

• --audit-log-xxx:审计日志

• 启动聚合层相关配置:–requestheader-client-ca-file,–proxy-client-cert-file,–proxy-client-key-file,–requestheader-allowed-names,–requestheader-extra-headers-prefix,–requestheader-group-headers,–requestheader-username-headers,–enable-aggregator-routing

更多参数参考官网:https://kubernetes.io/docs/reference/command-line-tools-reference/kube-apiserver/

2. 拷贝刚才生成的证书

把刚才生成的证书拷贝到配置文件中的路径:

cp ~/TLS/k8s/ca*pem ~/TLS/k8s/server*pem /opt/kubernetes/ssl/
3.启用TLS Bootstrapping机制

TLS Bootstraping:Master apiserver启用TLS认证后,Node节点kubelet和kube-proxy要与kube-apiserver进行通信,必须使用CA签发的有效证书才可以,当Node节点很多时,这种客户端证书颁发需要大量工作,同样也会增加集群扩展复杂度。为了简化流程,Kubernetes引入了TLS bootstraping机制来自动颁发客户端证书,kubelet会以一个低权限用户自动向apiserver申请证书,kubelet的证书由apiserver动态签署。所以强烈建议在Node上使用这种方式,目前主要用于kubelet,kube-proxy还是由我们统一颁发一个证书。

二进制部署高可用k8s集群

创建上述配置文件中token文件

#
[root@k8s-master1 ~]# head -c 16 /dev/urandom | od -An -t x | tr -d ' '
b3b4dba5e64a204dc03479e03ecf1588


cat > /opt/kubernetes/cfg/token.csv << EOF
b3b4dba5e64a204dc03479e03ecf1588,kubelet-bootstrap,10001,"system:node-bootstrapper"
EOF

格式:token,用户名,UID,用户组
token 也可以自行生成替换:
head -c 16 /dev/urandom | od -An -t x | tr -d ' '

命令注释:
head 显示文件的开头部分
-c, --bytes=[-]NUM       显示前NUM字节;如果NUM前有"-",那么会打印除了文件末尾的NUM字节以外的其他内容。

od 输出文件的八进制、十六进制等格式编码的字节
-A:<字码基数>:选择以何种基数计算字码;
-t<输出格式>或--format=<输出格式>:设置输出格式;

tr
将字符进行替换压缩和删除
-d或——delete:删除所有属于第一字符集的字符;

4.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

5.启动并设置开机启动
systemctl daemon-reload
systemctl start kube-apiserver 
systemctl enable kube-apiserver

4.5 部署kube-controller-manager

1.创建配置文件
cat > /opt/kubernetes/cfg/kube-controller-manager.conf << EOF
KUBE_CONTROLLER_MANAGER_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--leader-elect=true \\
--kubeconfig=/opt/kubernetes/cfg/kube-controller-manager.kubeconfig \\
--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 \\
--cluster-signing-duration=87600h0m0s"
EOF

• --kubeconfig:连接apiserver配置文件

• --leader-elect:当该组件启动多个时,自动选举(HA)

• --cluster-signing-cert-file/–cluster-signing-key-file:自动为kubelet颁发证书的CA,与apiserver保持一致

2.生成kubeconfig文件

切换工作目录

cd ~/TLS/k8s

创建证书请求文件

cat > kube-controller-manager-csr.json << EOF
{
  "CN": "system:kube-controller-manager",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing", 
      "ST": "BeiJing",
      "O": "system:masters",
      "OU": "System"
    }
  ]
}
EOF

生成证书

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

生成kubeconfig文件(以下是shell命令,直接在终端执行):

KUBE_CONFIG="/opt/kubernetes/cfg/kube-controller-manager.kubeconfig"
KUBE_APISERVER="https://172.21.51.71:6443"

kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials kube-controller-manager \
  --client-certificate=./kube-controller-manager.pem \
  --client-key=./kube-controller-manager-key.pem \
  --embed-certs=true \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-controller-manager \
  --kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}

3. 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

4.启动并设置开机启动
systemctl daemon-reload
systemctl start kube-controller-manager
systemctl enable kube-controller-manager

####4.6 部署kube-scheduler

1.创建配置文件
cat > /opt/kubernetes/cfg/kube-scheduler.conf << EOF
KUBE_SCHEDULER_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--leader-elect \\
--kubeconfig=/opt/kubernetes/cfg/kube-scheduler.kubeconfig \\
--bind-address=127.0.0.1"
EOF

–kubeconfig:连接apiserver配置文件

–leader-elect:当该组件启动多个时,自动选举(HA)

2.生成kubeconfig文件

生成kube-scheduler证书

切换目录

cd ~/TLS/k8s

创建证书请求文件

cat > kube-scheduler-csr.json << EOF
{
  "CN": "system:kube-scheduler",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing",
      "ST": "BeiJing",
      "O": "system:masters",
      "OU": "System"
    }
  ]
}
EOF

生成证书文件

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

生成kubeconfig文件

KUBE_CONFIG="/opt/kubernetes/cfg/kube-scheduler.kubeconfig"
KUBE_APISERVER="https://172.21.51.71:6443"

kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials kube-scheduler \
  --client-certificate=./kube-scheduler.pem \
  --client-key=./kube-scheduler-key.pem \
  --embed-certs=true \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-scheduler \
  --kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}

3.systemctl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

4.启动并设置开机启动
systemctl daemon-reload
systemctl start kube-scheduler
systemctl enable kube-scheduler

5.查看集群状态

生成kubectl连接集群的证书

cat > admin-csr.json <<EOF
{
  "CN": "admin",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing",
      "ST": "BeiJing",
      "O": "system:masters",
      "OU": "System"
    }
  ]
}
EOF

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

生成kubeconfig文件

mkdir /root/.kube

KUBE_CONFIG="/root/.kube/config"
KUBE_APISERVER="https://172.21.51.71:6443"

kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials cluster-admin \
  --client-certificate=./admin.pem \
  --client-key=./admin-key.pem \
  --embed-certs=true \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
  --cluster=kubernetes \
  --user=cluster-admin \
  --kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}



通过kubectl工具查看当前集群组件状态

[root@k8s-master1 k8s]# kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
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"}   

如上输出说明master节点组件运行正常。

6.授权kubelet-bootstrap用户允许请求证书
kubectl create clusterrolebinding kubelet-bootstrap \
--clusterrole=system:node-bootstrapper \
--user=kubelet-bootstrap

五 部署worker Node

下面还是在master node上操作,即同时作为worker node,主从复用

5.1 创建工作目录并拷贝二进制文件

在所有worker node 创建工作目录

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

从master节点拷贝

从master节点拷贝:
cd /root/kubernetes/server/bin/

cp kubelet kube-proxy /opt/kubernetes/bin   # 本地拷贝

####5.2 部署kubelet

1.创建配置文件
cat > /opt/kubernetes/cfg/kubelet.conf << EOF
KUBELET_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--hostname-override=k8s-master1 \\
--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"
EOF

• --hostname-override:显示名称,集群中唯一

• --network-plugin:启用CNI

• --kubeconfig:空路径,会自动生成,后面用于连接apiserver

• --bootstrap-kubeconfig:首次启动向apiserver申请证书

• --config:配置参数文件

• --cert-dir:kubelet证书生成目录

• --pod-infra-container-image:管理Pod网络容器的镜像

2. 配置参数文件
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

3.生成kubelet初次加入集群引导kubeconfig文件
KUBE_CONFIG="/opt/kubernetes/cfg/bootstrap.kubeconfig"
KUBE_APISERVER="https://172.21.51.71:6443" # apiserver IP:PORT
TOKEN="b3b4dba5e64a204dc03479e03ecf1588" # 与token.csv里保持一致

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

4.systemctl 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

5.启动并设置开机启动
systemctl daemon-reload
systemctl start kubelet
systemctl enable kubelet

5.3 批准kubelet证书申请并加入集群

查看kubelet证书请求
[root@k8s-master1 bin]# kubectl get csr
NAME                                                   AGE   SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-CwXx8GWIrGkN6OQeNyA9O08dYQWremUrLYJjH9bKa6k   45s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending

# 批准申请
kubectl certificate approve node-csr-CwXx8GWIrGkN6OQeNyA9O08dYQWremUrLYJjH9bKa6k

# 查看节点
[root@k8s-master1 bin]# kubectl get node
NAME          STATUS     ROLES    AGE   VERSION
k8s-master1   NotReady   <none>   13s   v1.20.9

由于网络插件还没部署,所有节点没有准备就绪,NotReady

5.4 部署kube-proxy

1.创建配置文件
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

2.配置参数文件
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-master1
clusterCIDR: 10.244.0.0/16
EOF

3.生成kube-proxy.kubeconfig文件
# 切换工作目录
cd ~/TLS/k8s

# 创建证书请求文件
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

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

生成kubeconfig文件:
KUBE_CONFIG="/opt/kubernetes/cfg/kube-proxy.kubeconfig"
KUBE_APISERVER="https://172.21.51.71:6443"

kubectl config set-cluster kubernetes \
  --certificate-authority=/opt/kubernetes/ssl/ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials kube-proxy \
  --client-certificate=./kube-proxy.pem \
  --client-key=./kube-proxy-key.pem \
  --embed-certs=true \
  --kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-proxy \
  --kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}

4.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

5.启动并设置开机启动
systemctl daemon-reload
systemctl start kube-proxy
systemctl enable kube-proxy

5.5 部署络组件

calico是一个纯三层的数据中心网络方案,是目前kubernetes主流网络方案

部署calico

mkdir -p /home/yaml
cd /home/yaml
wget https://docs.projectcalico.org/manifests/calico.yaml
#修改YAML:
#下载完后还需要修改里面定义Pod网络(CALICO_IPV4POOL_CIDR),与前面kube-controller-manager配置文件指定的cluster-cidr网段一样10.244.0.0/16
sed -i "3685,3686s/# //" calico.yaml
sed -i "3686s#192.168.0.0/16#10.244.0.0/16#" calico.yaml 


# 网络插件下载地址
wget https://github.com/containernetworking/plugins/releases/download/v1.0.0/cni-plugins-linux-amd64-v1.0.0.tgz



kubectl apply -f calico.yaml
kubectl get pods -n kube-system

等Calico Pod都Running,节点也会准备就绪:
[root@k8s-master1 yaml]# kubectl get node
NAME          STATUS   ROLES    AGE   VERSION
k8s-master1   Ready    <none>   80m   v1.20.9

5.6授权apiserver访问kubelet

应用场景:例如kubectl logs

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work node

1,拷贝已部署好的node相关文件到新节点
在Master节点将Worker Node涉及文件拷贝到新节点172.21.51.72/73

scp -r /opt/kubernetes root@172.21.51.72:/opt/
scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service root@172.21.51.72:/usr/lib/systemd/system
scp /opt/kubernetes/ssl/ca.pem root@172.21.51.72:/opt/kubernetes/ssl


scp -r /opt/kubernetes root@172.21.51.73:/opt/
scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service root@172.21.51.73:/usr/lib/systemd/system
scp /opt/kubernetes/ssl/ca.pem root@172.21.51.73:/opt/kubernetes/ssl
2.删除kubelet证书和kubeconfig文件
rm -f /opt/kubernetes/cfg/kubelet.kubeconfig 
rm -f /opt/kubernetes/ssl/kubelet*
注:这几个文件是证书申请审批后自动生成的,每个Node不同,必须删除
3.修改主机名
vi /opt/kubernetes/cfg/kubelet.conf
--hostname-override=k8s-node1

vi /opt/kubernetes/cfg/kube-proxy-config.yml
hostnameOverride: k8s-node1

vi /opt/kubernetes/cfg/kubelet.conf
--hostname-override=k8s-node2

vi /opt/kubernetes/cfg/kube-proxy-config.yml
hostnameOverride: k8s-node2
4.启动并设置开机启动
systemctl daemon-reload
systemctl start kubelet kube-proxy
systemctl enable kubelet kube-proxy
systemctl status kube-proxy
5.在master是批准新node kubelet 证书申请
# 查看证书请求
[root@k8s-master1 yaml]# kubectl get csr
NAME                                                   AGE   SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-7_86FVcMARHpAsrJ-yWWBXyOpg4R-RkgXVkygl3nK_Q   63s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending
node-csr-CwXx8GWIrGkN6OQeNyA9O08dYQWremUrLYJjH9bKa6k   94m   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Approved,Issued
node-csr-xVyN-IRcm9QKYLaIBjFx0eZGqAtgstWvAZuanLTUbVo   62s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending


# 授权请求
kubectl certificate approve node-csr-7_86FVcMARHpAsrJ-yWWBXyOpg4R-RkgXVkygl3nK_Q
kubectl certificate approve node-csr-xVyN-IRcm9QKYLaIBjFx0eZGqAtgstWvAZuanLTUbVo 

# 这里不小心把node2当成node1 加入了,master端有批准了,导致node无法加入,后面在etcd中删除对应的证书申请,重新加入恢复正常,Linux一切皆是文件
[root@k8s-master1 ~]# kubectl get csr
NAME                                                   AGE    SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-7_86FVcMARHpAsrJ-yWWBXyOpg4R-RkgXVkygl3nK_Q   42m    kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Approved,Issued
node-csr-CwXx8GWIrGkN6OQeNyA9O08dYQWremUrLYJjH9bKa6k   136m   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Approved,Issued
node-csr-Dc73TLG03NpqmGYfXSCCNORzMHKUvhyFLYzobPTfVMM   7s     kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending

kubectl certificate approve node-csr-Dc73TLG03NpqmGYfXSCCNORzMHKUvhyFLYzobPTfVMM 
6.查看node状态
[root@k8s-master1 ~]# kubectl get node
NAME          STATUS   ROLES    AGE    VERSION
k8s-master1   Ready    <none>   138m   v1.20.9
k8s-node1     Ready    <none>   43m    v1.20.9
k8s-node2     Ready    <none>   17s    v1.20.9

六 部署dashboards 和 coredns

6.1部署dashboards

wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta8/aio/deploy/recommended.yaml
[root@k8s-master1 ~]# cd /home/yaml/
[root@k8s-master1 yaml]# ls
apiserver-to-kubelet-rbac.yaml  calico.yaml
[root@k8s-master1 yaml]# vim recommended.yaml
默认Dashboard只能集群内部访问,修改Service为NodePort类型,暴露到外部:
# 修改Service为NodePort类型,文件的45行上下
......
kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
spec:
  ports:
    - port: 443
      targetPort: 8443
  selector:
    k8s-app: kubernetes-dashboard
  type: NodePort  # 加上type=NodePort变成NodePort类型的服务
  
---
...
kubectl apply -f recommended.yaml 
[root@k8s-master1 yaml]# kubectl get pods,svc -n kubernetes-dashboard
NAME                                             READY   STATUS    RESTARTS   AGE
pod/dashboard-metrics-scraper-7445d59dfd-kf4fr   1/1     Running   0          46s
pod/kubernetes-dashboard-7d8466d688-7cknh        1/1     Running   0          46s

NAME                                TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)         AGE
service/dashboard-metrics-scraper   ClusterIP   10.0.0.238   <none>        8000/TCP        46s
service/kubernetes-dashboard        NodePort    10.0.0.184   <none>        443:30026/TCP   46s

访问地址:https://NodeIP:30026 https://172.21.51.71:30026/

创建service account 并绑定默认cluster-admin管理员集群角色

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}')
root@k8s-master1 yaml]# kubectl create serviceaccount dashboard-admin -n kube-system
serviceaccount/dashboard-admin created
[root@k8s-master1 yaml]# kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
clusterrolebinding.rbac.authorization.k8s.io/dashboard-admin created
[root@k8s-master1 yaml]# kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk '/dashboard-admin/{print $1}')
Name:         dashboard-admin-token-9nrwn
Namespace:    kube-system
Labels:       <none>
Annotations:  kubernetes.io/service-account.name: dashboard-admin
              kubernetes.io/service-account.uid: f58b4bfb-171b-4ccd-8714-7fa6bbe4f05a

Type:  kubernetes.io/service-account-token

Data
====
ca.crt:     1359 bytes
namespace:  11 bytes
token:      eyJhbGciOiJSUzI1NiIsImtpZCI6InMwWC0tYzVybnRCM3hDLW9GMGtlZk50LWRPZWV5RFNDbm5LTHBWUVhXUlEifQ.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.bRTyoT_F9LKpX5U9d0iDM6Jtw7IBDptGMnxST7UYlQ5F8oQ8CeHORTzrmFZQ_1qVzWj6SjvUfXv_mPvIrnPTTvhYiS9-xxeIQCeCV5r4Sx2gqFkFxNipOt995trKxBZ4JtQQ8bPdKedXur5LYUg1SEtZsx8bNCPFNDpcYjh7NwH02xs9Sxs6OUUjNDswumk2JleAAwiIqxpCcFhflz5Xsbo6fCtqwnzWapIv84PAoDQYXOPBCIavvu8M7VA76UHQoX5ZgSnpUZw-A3TmeFKjEiuoRl_5ZN_LZ-zAReJ4ws0OiSDlh2tOxqZViPTaKOIltdEyrJCeoZhkrZLIKpJnpw
[root@k8s-master1 yaml]# 

6.2 部署coreDNS

coreDNS用于集群内部service名称解析

apiVersion: v1
kind: ServiceAccount
metadata:
  name: coredns
  namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
  name: system:coredns
rules:
- apiGroups:
  - ""
  resources:
  - endpoints
  - services
  - pods
  - namespaces
  verbs:
  - list
  - watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  annotations:
    rbac.authorization.kubernetes.io/autoupdate: "true"
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
  name: system:coredns
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:coredns
subjects:
- kind: ServiceAccount
  name: coredns
  namespace: kube-system
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: coredns
  namespace: kube-system
data:
  Corefile: |
    .:53 {
        errors
        health {
          lameduck 5s
        }
        ready
        kubernetes cluster.local  in-addr.arpa ip6.arpa {
          fallthrough in-addr.arpa ip6.arpa
        }
        prometheus :9153
        forward . /etc/resolv.conf {
          max_concurrent 1000
        }
        cache 30
        loop
        reload
        loadbalance
    }
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: coredns
  namespace: kube-system
  labels:
    k8s-app: kube-dns
    kubernetes.io/name: "CoreDNS"
spec:
  # replicas: not specified here:
  # 1. Default is 1.
  # 2. Will be tuned in real time if DNS horizontal auto-scaling is turned on.
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxUnavailable: 1
  selector:
    matchLabels:
      k8s-app: kube-dns
  template:
    metadata:
      labels:
        k8s-app: kube-dns
    spec:
      priorityClassName: system-cluster-critical
      serviceAccountName: coredns
      tolerations:
        - key: "CriticalAddonsOnly"
          operator: "Exists"
      nodeSelector:
        kubernetes.io/os: linux
      affinity:
         podAntiAffinity:
           preferredDuringSchedulingIgnoredDuringExecution:
           - weight: 100
             podAffinityTerm:
               labelSelector:
                 matchExpressions:
                   - key: k8s-app
                     operator: In
                     values: ["kube-dns"]
               topologyKey: kubernetes.io/hostname
      containers:
      - name: coredns
        image: coredns/coredns:1.8.0
        imagePullPolicy: IfNotPresent
        resources:
          limits:
            memory: 170Mi
          requests:
            cpu: 100m
            memory: 70Mi
        args: [ "-conf", "/etc/coredns/Corefile" ]
        volumeMounts:
        - name: config-volume
          mountPath: /etc/coredns
          readOnly: true
        ports:
        - containerPort: 53
          name: dns
          protocol: UDP
        - containerPort: 53
          name: dns-tcp
          protocol: TCP
        - containerPort: 9153
          name: metrics
          protocol: TCP
        securityContext:
          allowPrivilegeEscalation: false
          capabilities:
            add:
            - NET_BIND_SERVICE
            drop:
            - all
          readOnlyRootFilesystem: true
        livenessProbe:
          httpGet:
            path: /health
            port: 8080
            scheme: HTTP
          initialDelaySeconds: 60
          timeoutSeconds: 5
          successThreshold: 1
          failureThreshold: 5
        readinessProbe:
          httpGet:
            path: /ready
            port: 8181
            scheme: HTTP
      dnsPolicy: Default
      volumes:
        - name: config-volume
          configMap:
            name: coredns
            items:
            - key: Corefile
              path: Corefile
---
apiVersion: v1
kind: Service
metadata:
  name: kube-dns
  namespace: kube-system
  annotations:
    prometheus.io/port: "9153"
    prometheus.io/scrape: "true"
  labels:
    k8s-app: kube-dns
    kubernetes.io/cluster-service: "true"
    kubernetes.io/name: "CoreDNS"
spec:
  selector:
    k8s-app: kube-dns
  clusterIP: 10.0.0.2
  ports:
  - name: dns
    port: 53
    protocol: UDP
  - name: dns-tcp
    port: 53
    protocol: TCP
  - name: metrics
    port: 9153
    protocol: TCP
kubectl apply -f coredns.yaml  
kubectl get pods -n kube-system  
docker pull coredns/coredns:1.8.0

6.3DNS解析测试

[root@k8s-master1 yaml]# 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

七 扩容多Master(高可用架构 )

kubernetes作为容器集群系统,通过监控检查+重启策略实现了pod故障自我修复能力,听过调度算法实现将pod分布式部署,并保存预期副本数,根据node失效状态自动在其他node上拉取pod,实现了应用层的高可用性。

针对Kubernetes集群,高可用性还应包含以下两个层面的考虑:Etcd数据库的高可用性和Kubernetes Master组件的高可用性。 而Etcd我们已经采用3个节点组建集群实现高可用,本节将对Master节点高可用进行说明和实施。

Master节点扮演着总控中心的角色,通过不断与工作节点上的Kubelet和kube-proxy进行通信来维护整个集群的健康工作状态。如果Master节点故障,将无法使用kubectl工具或者API做任何集群管理。

Master节点主要有三个服务kube-apiserver,kube-controller-manager和kube-scheduler,其中kube-controller-manager和kube-scheduler组件自身通过选择机制已经实现了高可用,所有master高可用主要针对kube-apiserver组件,而该组件以Http api提供服务,因此对他高可用与web服务器类型,增加负载均衡器对其负载均衡即可,并且可以水平宽容。

多master架构图:

二进制部署高可用k8s集群

7.1部署master2 node

Master2 与已部署的Master1所有操作一致。所以我们只需将Master1所有K8s文件拷贝过来,再修改下服务器IP和主机名启动即可。

1.安装docker
scp /usr/bin/docker* root@172.21.51.74:/usr/bin
scp /usr/bin/runc root@172.21.51.74:/usr/bin
scp /usr/bin/containerd* root@172.21.51.74:/usr/bin
scp /usr/lib/systemd/system/docker.service root@172.21.51.74:/usr/lib/systemd/system
scp -r /etc/docker root@172.21.51.74:/etc

# 在Master2启动Docker
systemctl daemon-reload
systemctl start docker
systemctl enable docker

2. 创建etcd 证书目录

在master2创建etcd证书目录

mkdir -p /opt/etcd/ssl
3.拷贝文件(master操作)

拷贝Master1上所有K8s文件和etcd证书到Master2

scp -r /opt/kubernetes root@172.21.51.74:/opt
scp -r /opt/etcd/ssl root@172.21.51.74:/opt/etcd
scp /usr/lib/systemd/system/kube* root@172.21.51.74:/usr/lib/systemd/system
scp /usr/bin/kubectl  root@172.21.51.74:/usr/bin
scp -r ~/.kube root@172.21.51.74:~

4.删除证书文件
rm -f /opt/kubernetes/cfg/kubelet.kubeconfig 
rm -f /opt/kubernetes/ssl/kubelet*

5.修改配置文件ip和主机名

修改apiserver,kubelet和kube-proxy配置文件为本地IP:

vi /opt/kubernetes/cfg/kube-apiserver.conf 
...
--bind-address=172.21.51.74 \
--advertise-address=172.21.51.74 \
...

vi /opt/kubernetes/cfg/kube-controller-manager.kubeconfig
server: https://172.21.51.74:6443

vi /opt/kubernetes/cfg/kube-scheduler.kubeconfig
server: https://172.21.51.74:6443

vi /opt/kubernetes/cfg/kubelet.conf
--hostname-override=k8s-master2

vi /opt/kubernetes/cfg/kube-proxy-config.yml
hostnameOverride: k8s-master2

vi ~/.kube/config
...
server: https://172.21.51.74:6443

6.启动设置开机启动
systemctl daemon-reload
systemctl start kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy
systemctl enable kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy

7.查看集群状态
[root@k8s-master2 ~]# kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
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"}   

8.批准kubelet证书申请
[root@k8s-master2 ~]# kubectl get csr
NAME                                                   AGE   SIGNERNAME                                    REQUESTOR           CONDITION
node-csr-KjsoM5QmVBJmCjnyU4u1Hdm2ipxwCOo4qewY3X_egNc   80s   kubernetes.io/kube-apiserver-client-kubelet   kubelet-bootstrap   Pending

[root@k8s-master2 ~]# kubectl certificate approve node-csr-KjsoM5QmVBJmCjnyU4u1Hdm2ipxwCOo4qewY3X_egNc 
certificatesigningrequest.certificates.k8s.io/node-csr-KjsoM5QmVBJmCjnyU4u1Hdm2ipxwCOo4qewY3X_egNc approved
[root@k8s-master2 ~]# kubectl get node
NAME          STATUS   ROLES    AGE     VERSION
k8s-master1   Ready    <none>   4h13m   v1.20.9
k8s-master2   Ready    <none>   43s     v1.20.9
k8s-node1     Ready    <none>   158m    v1.20.9
k8s-node2     Ready    <none>   115m    v1.20.9



72. 设置kubectl自动补全

 yum install bash-completion -y
 source /usr/share/bash-completion/bash_completion
 source <(kubectl completion bash)
 echo "source <(kubectl completion bash)" >> ~/.bashrc

7.3 部署Nginx+Keeplived 高可用负载均衡

kube-apiserver高可用架构图

二进制部署高可用k8s集群

  • nginx是一个主流web服务和反向代理服务器,这里用四层实现对apiserver实现负载均衡
  • Keepalived是一个主流高可用软件,基于VIP绑定实现服务器双机热备,在上述拓扑图中,Keepalived主要根据nginx运行状态判断是否需要故障转移(漂移VIP),例如当nginx主节点挂掉,VIP会自动绑定在nginx备节点,从而保证VIP一致可用,实现nginx高可用

注1:为了节省机器,这里与K8s Master节点机器复用。也可以独立于k8s集群之外部署,只要nginx与apiserver能通信就行。

注2:如果你是在公有云上,一般都不支持keepalived,那么你可以直接用它们的负载均衡器产品,直接负载均衡多台Master kube-apiserver,架构与上面一样。如阿里云slb。

1.安装软件包(主备)
 yum install epel-release -y
 yum install nginx keepalived -y

2.nginx配置文件(主备一致)
cat > /etc/nginx/nginx.conf << "EOF"
user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;

include /usr/share/nginx/modules/*.conf;

events {
    worker_connections 1024;
}

# 四层负载均衡,为两台Master apiserver组件提供负载均衡
stream {

    log_format  main  '$remote_addr $upstream_addr - [$time_local] $status $upstream_bytes_sent';

    access_log  /var/log/nginx/k8s-access.log  main;

    upstream k8s-apiserver {
       server 172.21.51.71:6443;   # Master1 APISERVER IP:PORT
       server 172.21.51.74:6443;   # Master2 APISERVER IP:PORT
    }
    
    server {
       listen 16443; # 由于nginx与master节点复用,这个监听端口不能是6443,否则会冲突
       proxy_pass k8s-apiserver;
    }
}

http {
    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile            on;
    tcp_nopush          on;
    tcp_nodelay         on;
    keepalive_timeout   65;
    types_hash_max_size 2048;

    include             /etc/nginx/mime.types;
    default_type        application/octet-stream;

    server {
        listen       80 default_server;
        server_name  _;

        location / {
        }
    }
}
EOF

3.Keepalived配置文件
cat > /etc/keepalived/keepalived.conf << EOF
global_defs { 
   notification_email { 
     acassen@firewall.loc 
     failover@firewall.loc 
     sysadmin@firewall.loc 
   } 
   notification_email_from Alexandre.Cassen@firewall.loc  
   smtp_server 127.0.0.1 
   smtp_connect_timeout 30 
   router_id NGINX_MASTER
} 

vrrp_script check_nginx {
    script "/etc/keepalived/check_nginx.sh"
}

vrrp_instance VI_1 { 
    state MASTER 
    interface ens33  # 修改为实际网卡名
    virtual_router_id 51 # VRRP 路由 ID实例,每个实例是唯一的 
    priority 100    # 优先级,备服务器设置 90 
    advert_int 1    # 指定VRRP 心跳包通告间隔时间,默认1秒 
    authentication { 
        auth_type PASS      
        auth_pass 1111 
    }  
    # 虚拟IP
    virtual_ipaddress { 
        172.21.51.88/24
    } 
    track_script {
        check_nginx
    } 
}
EOF

•	vrrp_script:指定检查nginx工作状态脚本(根据nginx状态判断是否故障转移)
•	virtual_ipaddress:虚拟IP(VIP)

准备上述配置文件中检查nginx运行状态的脚本:
cat > /etc/keepalived/check_nginx.sh  << "EOF"
#!/bin/bash
count=$(ss -antp |grep 16443 |egrep -cv "grep|$$")

if [ "$count" -eq 0 ];then
    exit 1
else
    exit 0
fi
EOF

chmod +x /etc/keepalived/check_nginx.sh
4.Keepalived配置文件(nginx backup)
cat > /etc/keepalived/keepalived.conf << EOF
global_defs { 
   notification_email { 
     acassen@firewall.loc 
     failover@firewall.loc 
     sysadmin@firewall.loc 
   } 
   notification_email_from Alexandre.Cassen@firewall.loc  
   smtp_server 127.0.0.1 
   smtp_connect_timeout 30 
   router_id NGINX_BACKUP
} 

vrrp_script check_nginx {
    script "/etc/keepalived/check_nginx.sh"
}

vrrp_instance VI_1 { 
    state BACKUP 
    interface ens33
    virtual_router_id 51 # VRRP 路由 ID实例,每个实例是唯一的 
    priority 90
    advert_int 1
    authentication { 
        auth_type PASS      
        auth_pass 1111 
    }  
    virtual_ipaddress { 
        172.21.51.88/24
    } 
    track_script {
        check_nginx
    } 
}
EOF

准备上述配置文件中检查nginx运行状态的脚本:

cat > /etc/keepalived/check_nginx.sh  << "EOF"
#!/bin/bash
count=$(ss -antp |grep 16443 |egrep -cv "grep|$$")

if [ "$count" -eq 0 ];then
    exit 1
else
    exit 0
fi
EOF
chmod +x /etc/keepalived/check_nginx.sh

注:keepalived根据脚本返回状态码(0为工作正常,非0不正常)判断是否故障转移。

5.启动并设置开机启动
systemctl daemon-reload
systemctl start nginx keepalived
systemctl enable nginx keepalived

[root@k8s-master1 ~]# systemctl status  nginx 
● nginx.service - The nginx HTTP and reverse proxy server
   Loaded: loaded (/usr/lib/systemd/system/nginx.service; enabled; vendor preset: disabled)
   Active: failed (Result: exit-code) since Sun 2021-08-15 06:14:50 CST; 26s ago
  Process: 56349 ExecStartPre=/usr/sbin/nginx -t (code=exited, status=1/FAILURE)
  Process: 56347 ExecStartPre=/usr/bin/rm -f /run/nginx.pid (code=exited, status=0/SUCCESS)

Aug 15 06:14:50 k8s-master1 systemd[1]: Starting The nginx HTTP and reverse proxy server...
Aug 15 06:14:50 k8s-master1 nginx[56349]: nginx: [emerg] unknown directive "stream" in /etc/nginx/nginx.conf:13
Aug 15 06:14:50 k8s-master1 nginx[56349]: nginx: configuration file /etc/nginx/nginx.conf test failed
Aug 15 06:14:50 k8s-master1 systemd[1]: nginx.service: control process exited, code=exited status=1
Aug 15 06:14:50 k8s-master1 systemd[1]: Failed to start The nginx HTTP and reverse proxy server.
Aug 15 06:14:50 k8s-master1 systemd[1]: Unit nginx.service entered failed state.
Aug 15 06:14:50 k8s-master1 systemd[1]: nginx.service failed.

需要下stream模块
yum install nginx-mod-stream -y

nginx -t
6. 查看keepalived工作状态
[root@k8s-master1 ~]# ip addr | grep 172
    inet 172.21.51.71/24 brd 172.21.51.255 scope global noprefixroute ens33
    inet 172.21.51.88/24 scope global secondary ens33
    inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0

可以看到,在ens33网卡绑定了172.21.51.88 虚拟IP,说明工作正常。

7.nginx+Keepalived高可用测试

关闭主节点nginx,测试vip是否漂移到备节点服务器

[root@k8s-master1 ~]# systemctl stop nginx

[root@k8s-master2 ~]# ip addr | grep 88
    inet 172.21.51.88/24 scope global secondary ens33

8.访问负载均衡器测试

找k8s集群中任意一个节点,使用curl ,使用curl查看k8s版本测试,使用vip访问

[root@k8s-node2 ~]# curl -k https://172.21.51.88:16443/version
{
  "major": "1",
  "minor": "20",
  "gitVersion": "v1.20.9",
  "gitCommit": "7a576bc3935a6b555e33346fd73ad77c925e9e4a",
  "gitTreeState": "clean",
  "buildDate": "2021-07-15T20:56:38Z",
  "goVersion": "go1.15.14",
  "compiler": "gc",
  "platform": "linux/amd64"

可以正确获取到k8s版本信息,说明负载均衡器搭建正常,该请求数据流程:

curl -> vip(nginx) -> apiserver

通过查看nginx日志也可以看到转发apiserver ip

[root@k8s-master2 ~]# tail /var/log/nginx/k8s-access.log -f
172.21.51.73 172.21.51.74:6443 - [15/Aug/2021:06:31:27 +0800] 200 420
172.21.51.73 172.21.51.71:6443 - [15/Aug/2021:06:31:32 +0800] 200 420
172.21.51.73 172.21.51.71:6443 - [15/Aug/2021:06:31:34 +0800] 200 420
172.21.51.73 172.21.51.74:6443 - [15/Aug/2021:06:31:35 +0800] 200 420

7.4修改所有worker node 连接LB VIP

试想下,虽然我们增加了Master2 Node和负载均衡器,但是我们是从单Master架构扩容的,也就是说目前所有的Worker Node组件连接都还是Master1 Node,如果不改为连接VIP走负载均衡器,那么Master还是单点故障。

因此接下来就是要改所有Worker Node(kubectl get node命令查看到的节点)组件配置文件,由原来172.21.51.71修改为172.21.51.88(VIP)。

在所有Worker Node执行:

sed -i 's#172.21.51.71:6443#172.21.51.88:16443#' /opt/kubernetes/cfg/*
systemctl restart kubelet kube-proxy

检查节点状态

[root@k8s-master1 ~]# kubectl get node
NAME          STATUS   ROLES    AGE     VERSION
k8s-master1   Ready    <none>   4h56m   v1.20.9
k8s-master2   Ready    <none>   44m     v1.20.9
k8s-node1     Ready    <none>   3h22m   v1.20.9
k8s-node2     Ready    <none>   158m    v1.20.9

failed state.
Aug 15 06:14:50 k8s-master1 systemd[1]: nginx.service failed.

需要下stream模块
yum install nginx-mod-stream -y

nginx -t


###### 6. 查看keepalived工作状态

[root@k8s-master1 ~]# ip addr | grep 172
inet 172.21.51.71/24 brd 172.21.51.255 scope global noprefixroute ens33
inet 172.21.51.88/24 scope global secondary ens33
inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0


可以看到,在ens33网卡绑定了172.21.51.88 虚拟IP,说明工作正常。

##### 7.nginx+Keepalived高可用测试

关闭主节点nginx,测试vip是否漂移到备节点服务器

[root@k8s-master1 ~]# systemctl stop nginx

[root@k8s-master2 ~]# ip addr | grep 88
inet 172.21.51.88/24 scope global secondary ens33


##### 8.访问负载均衡器测试

找k8s集群中任意一个节点,使用curl ,使用curl查看k8s版本测试,使用vip访问

[root@k8s-node2 ~]# curl -k https://172.21.51.88:16443/version
{
“major”: “1”,
“minor”: “20”,
“gitVersion”: “v1.20.9”,
“gitCommit”: “7a576bc3935a6b555e33346fd73ad77c925e9e4a”,
“gitTreeState”: “clean”,
“buildDate”: “2021-07-15T20:56:38Z”,
“goVersion”: “go1.15.14”,
“compiler”: “gc”,
“platform”: “linux/amd64”


可以正确获取到k8s版本信息,说明负载均衡器搭建正常,该请求数据流程:

curl -> vip(nginx) -> apiserver


通过查看nginx日志也可以看到转发apiserver ip 

[root@k8s-master2 ~]# tail /var/log/nginx/k8s-access.log -f
172.21.51.73 172.21.51.74:6443 - [15/Aug/2021:06:31:27 +0800] 200 420
172.21.51.73 172.21.51.71:6443 - [15/Aug/2021:06:31:32 +0800] 200 420
172.21.51.73 172.21.51.71:6443 - [15/Aug/2021:06:31:34 +0800] 200 420
172.21.51.73 172.21.51.74:6443 - [15/Aug/2021:06:31:35 +0800] 200 420


#### 7.4修改所有worker node 连接LB VIP

试想下,虽然我们增加了Master2 Node和负载均衡器,但是我们是从单Master架构扩容的,也就是说目前所有的Worker Node组件连接都还是Master1 Node,如果不改为连接VIP走负载均衡器,那么Master还是单点故障。

因此接下来就是要改所有Worker Node(kubectl get node命令查看到的节点)组件配置文件,由原来172.21.51.71修改为172.21.51.88(VIP)。

在所有Worker Node执行:

sed -i ‘s#172.21.51.71:6443#172.21.51.88:16443#’ /opt/kubernetes/cfg/*
systemctl restart kubelet kube-proxy


检查节点状态

[root@k8s-master1 ~]# kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready 4h56m v1.20.9
k8s-master2 Ready 44m v1.20.9
k8s-node1 Ready 3h22m v1.20.9
k8s-node2 Ready 158m v1.20.9



出自:http://www.aliangedu.cn


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