一、生产环境部署k8s常见的几种方式
说明:文章内使用到的yaml可到博客资源内下载 k8s-yaml
1、kubeadm
Kubeadm是一个K8s部署工具,提供kubeadm init和kubeadm join,用于快速部署Kubernetes集群。
2、二进制
从github下载发行版的二进制包,手动部署每个组件,组成Kubernetes集群。
小结:
Kubeadm降低部署门槛,但屏蔽了很多细节,遇到问题很难排查。如果想更容易可控,推荐使用二进制包部署Kubernetes集群,虽然手动部署
麻烦点,期间可以学习很多工作原理,也利于后期维护。
3、kubespray
Kubespray 是 Kubernetes incubator 中的项目,目标是提供 Production Ready Kubernetes 部署方案,该项目基础是通过 Ansible Playbook
来定义系统与 Kubernetes 集群部署的任务。
二、二进制部署
1、准备环境
服务器要求:
- 建议最小硬件配置: 2核CPU\2G内存\30G硬盘。
- 服务器最好可以访问外网,会有从网上拉取镜像的需求,如果服务器不能上网,需要提前下载对应镜像导入节点。
软件环境:
软件 | 版本 |
---|---|
操作系统 | CentOS7.x_x64(mini) |
容器引擎 | Docker Ce19 |
Kubernetes | Kubernetes V1.20 |
服务器规划:
角色 | IP | 组件 |
---|---|---|
k8s-master1 | 192.168.242.51 | kube-apiserver,kube-controller-manager,kube-scheduler,kubelet,kube-proxy,docker,etcd,nginx,keepalived |
k8s-master2 | 192.168.242.54 | kube-apiserver,kube-controller-manager,kube-scheduler,kubelet,kube-proxy,docker,nginx,keepalived |
k8s-node1 | 192.168.242.52 | kubelet,kube-proxy,docker,etcd |
k8s-node2 | 192.168.242.53 | kubelet,kube-proxy,docker,etcd |
负载均衡器(虚拟IP) | 192.168.242.55 |
须知:
考虑到有些朋友电脑配置较低,一次性开四台虚拟机电脑跑不动, 所以搭建这套k8s高可用集群分两部分实施,先部署一套单Master架构(三台),
再扩容为多Master架构(4台或6台), 顺便再熟悉下Master扩容流程。
单Master架构图
单Master服务器规划:
角色 | IP | 组件 |
---|---|---|
k8s-master | 192.168.242.51 | kube-apiserver,kube-controller-manager,kube-scheduler,etcd |
k8s-node1 | 192.168.242.52 | kubelet,kube-proxy,docker,etcd |
k8s-node2 | 192.168.242.53 | kubelet,kube-proxy,docker,etcd |
2、操作系统初始化配置(所有节点)
#关闭系统防火墙
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 k8s-master1
hostnamectl set-hostname k8s-master2
hostnamectl set-hostname k8s-node1
hostnamectl set-hostname k8s-node2
#添加hosts
cat >> /etc/hosts << EOF
192.168.242.51 k8s-master1
192.168.242.52 k8s-node1
192.168.242.53 k8s-node2
192.168.242.54 k8s-master2
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
#时间同步
#使用阿里云时间服务器进行临时同步
[root@k8s-node1 ~]# ntpdate ntp.aliyun.com
4 Sep 21:27:49 ntpdate[22399]: adjust time server 203.107.6.88 offset 0.001010 sec
#如需配置NTP服务可参考该文档
https://blog.csdn.net/qq_44078641/article/details/120071838
3、部署etcd集群
3.1 etcd简介
Etcd 是一个分布式键值存储系统,Kubernetes使用Etcd进行数据存储,所以先准备一个Etcd数据库,为解决Etcd单点故障,应采用集群方式部署,这里使用3台组建集群,可容忍1台机器故障,当然,你也可以使用5台组建集群,可容忍2台机器故障
3.2 服务器规划
节点名称 | IP |
---|---|
etcd-1 | 192.168.242.51 |
etcd-2 | 192.168.242.52 |
etcd-2 | 192.168.242.53 |
说明:
为了节省机器,这里与k8s节点复用,也可以部署在k8s机器之外,只要apiserver能连接到就行。
3.3 cfssl证书生成工具准备
cfssl简介:
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。
找任意一台服务器操作,这里用Master1节点。
#创建目录存放cfssl工具
mkdir /software-cfssl
#下载相关工具
wget https://pkg.cfssl.org/R1.2/cfssl_linux-amd64 -P /software-cfssl/
wget https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64 -P /software-cfssl/
wget https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64 -P /software-cfssl/
cd /software-cfssl/
chmod +x *
cp cfssl_linux-amd64 /usr/local/bin/cfssl
cp cfssljson_linux-amd64 /usr/local/bin/cfssljson
cp cfssl-certinfo_linux-amd64 /usr/bin/cfssl-certinfo
说明:
如果下载失败,可以使用文档中附件 cfssl工具包
3.4 自签证书颁发机构(CA)
3.4.1 创建工作目录
mkdir -p ~/TLS/{etcd,k8s}
cd ~/TLS/etcd/
3.4.2 生成自签CA配置
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": "YuMingYu",
"ST": "YuMingYu"
}
]
}
EOF
3.4.3 生成自签CA证书
cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
说明:
当前目录下会生成 ca.pem和ca-key.pem文件
[root@k8s-master1 etcd]# ls .
ca-config.json ca.csr ca-csr.json ca-key.pem ca.pem
3.5 使用自签CA签发etcd https证书
3.5.1 创建证书申请文件
cat > server-csr.json << EOF
{
"CN": "etcd",
"hosts": [
"192.168.242.51",
"192.168.242.52",
"192.168.242.53",
"192.168.242.54"
],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"L": "YuMingYu",
"ST": "YuMingYu"
}
]
}
EOF
说明:
上述文件hosts字段中ip为所有etcd节点的集群内部通信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。
3.5.2 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
说明:
当前目录下会生成 server.pem 和 server-key.pem
[root@k8s-master1 etcd]# ls
ca-config.json ca-csr.json ca.pem server-csr.json server.pem
ca.csr ca-key.pem server.csr server-key.pem
3.6 下载etcd二进制文件
下载地址
#下载后上传到服务器任意位置即可
https://github.com/etcd-io/etcd/releases/download/v3.4.9/etcd-v3.4.9-linux-amd64.tar.gz
说明:
如果下载有问题,可使用附件中的文件。
3.7 部署etcd集群
以下操作在master1上面操作,为简化操作,待会将master1节点生成的所有文件拷贝到其他节点。
3.7.1 创建工作目录并解压二进制包
mkdir /opt/etcd/{bin,cfg,ssl} -p
tar -xf etcd-v3.4.9-linux-amd64.tar.gz
mv etcd-v3.4.9-linux-amd64/{etcd,etcdctl} /opt/etcd/bin/
3.8 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://192.168.242.51:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.242.51:2379"
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.242.51:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.242.51:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.242.51:2380,etcd-2=https://192.168.242.52:2380,etcd-3=https://192.168.242.53:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF
配置说明:
- ETCD_NAME: 节点名称,集群中唯一
- ETCD_DATA_DIR:数据目录
- ETCD_LISTEN_PEER_URLS:集群通讯监听地址
- ETCD_LISTEN_CLIENT_URLS:客户端访问监听地址
- ETCD_INITIAL_CLUSTER:集群节点地址
- ETCD_INITIALCLUSTER_TOKEN:集群Token
- ETCD_INITIALCLUSTER_STATE:加入集群的状态:new是新集群,existing表示加入已有集群
3.9 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
3.10 将master1节点所有生成的文件拷贝到节点2和节点3
for i in {2..3}
do
scp -r /opt/etcd/ root@192.168.242.5$i:/opt/
scp /usr/lib/systemd/system/etcd.service root@192.168.242.5$i:/usr/lib/systemd/system/
done
3.11 修改节点2,节点3 ,etcd.conf配置文件中的节点名称和当前服务器IP:
#[Member]
ETCD_NAME="etcd-1" #节点2修改为: etcd-2 节点3修改为: etcd-3
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.242.51:2380" #修改为对应节点IP
ETCD_LISTEN_CLIENT_URLS="https://192.168.242.51:2379" #修改为对应节点IP
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.242.51:2380" #修改为对应节点IP
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.242.51:2379" #修改为对应节点IP
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.242.51:2380,etcd-2=https://192.168.242.52:2380,etcd-3=https://192.168.242.53:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
3.12 启动etcd并设置开机自启
说明:
etcd须多个节点同时启动,不然执行systemctl start etcd会一直卡在前台,连接其他节点,建议通过批量管理工具,或者脚本同时启动etcd。
systemctl daemon-reload
systemctl start etcd
systemctl enable etcd
3.13 检查etcd集群状态
[root@k8s-master1 ~]# 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://192.168.242.51:2379,https://192.168.242.52:2379,https://192.168.242.53:2379" endpoint health --write-out=table
+-----------------------------+--------+-------------+-------+
| ENDPOINT | HEALTH | TOOK | ERROR |
+-----------------------------+--------+-------------+-------+
| https://192.168.242.52:2379 | true | 67.267851ms | |
| https://192.168.242.51:2379 | true | 67.374967ms | |
| https://192.168.242.53:2379 | true | 69.244918ms | |
+-----------------------------+--------+-------------+-------+
如果为以上状态证明部署的没有问题
3.14 etcd问题排查(日志)
less /var/log/message
journalctl -u etcd
4、安装Docker(所有节点)
这里使用Docker作为容器引擎,也可以换成别的,例如containerd,k8s在1.20版本就不在支持docker
4.1 解压二进制包
wget https://download.docker.com/linux/static/stable/x86_64/docker-19.03.9.tgz
tar -xf docker-19.03.9.tgz
mv docker/* /usr/bin/
4.2 配置镜像加速
sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": ["https://3s9106.mirror.alncs.com"]
}
EOF
说明:
可参考: https://blog.csdn.net/qq_44078641/article/details/104366373
4.3 启动并设置开机启动
systemctl daemon-reload
systemctl start docker
systemctl enable docker
5、部署Master节点
5.1 生成kube-apiserver证书
5.1.1 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 -
目录下会生成 ca.pem 和 ca-key.pem
5.1.2 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",
"192.168.242.51",
"192.168.242.52",
"192.168.242.53",
"192.168.242.54",
"192.168.242.55",
"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
说明:
上述文件中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
说明:
当前目录下会生成server.pem 和 server-key.pem文件。
5.2 下载
下载地址:
https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.20.md
5.3 解压二进制包
上传刚才下载的k8s软件包到服务器上
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/
5.4 部署kube-apiserver
5.4.1 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://192.168.242.51:2379,https://192.168.242.52:2379,https://192.168.242.53:2379 \\
--bind-address=192.168.242.51 \\
--secure-port=6443 \\
--advertise-address=192.168.242.51 \\
--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
说明:
上面两个\\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
- --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 :启动授权
- --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
- 启动聚合层网关配置:--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
5.4.2 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/
5.4.3 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。
TLS bootstraping 工作流程:
创建上述配置文件中token文件:
cat > /opt/kubernetes/cfg/token.csv << EOF
4136692876ad4b01bb9dd0988480ebba,kubelet-bootstrap,10001,"system:node-bootstrapper"
EOF
格式:token,用户名,UID,用户组
token也可自行生成替换:
head -c 16 /dev/urandom | od -An -t x | tr -d ' '
5.4.4 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
5.4.5 启动并设置开机启动
systemctl daemon-reload
systemctl start kube-apiserver
systemctl enable kube-apiserver
5.5 部署kube-controller-manager
5.5.1 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 :自动为kubelet颁发证书的CA,apiserver保持一致
- --cluster-signing-key-file :自动为kubelet颁发证书的CA,apiserver保持一致
5.5.2 生成kubeconfig文件
生成kube-controller-manager证书 :
# 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shell终端执行)
KUBE_CONFIG="/opt/kubernetes/cfg/kube-controller-manager.kubeconfig"
KUBE_APISERVER="https://192.168.242.51:6443"
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=${KUBE_CONFIG}
5.5.3 systemd管理controller-manager
cat > /usr/lib/systemd/system/kube-controller-manager.service << EOF
[Unit]
Description=Kubernetes Controller Manager
Documentation=https://github.com/kubernetes/kubernetes
[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-controller-manager.conf
ExecStart=/opt/kubernetes/bin/kube-controller-manager \$KUBE_CONTROLLER_MANAGER_OPTS
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF
5.5.4 启动并设置开机自启
systemctl daemon-reload
systemctl start kube-controller-manager
systemctl enable kube-controller-manager
5.6 部署 kube-scheduler
5.6.1 创建配置文件
cat > /opt/kubernetes/cfg/kube-scheduler.conf << EOF
KUBE_SCHEDULER_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/opt/kubernetes/logs \\
--leader-elect \\
--kubeconfig=/opt/kubernetes/cfg/kube-scheduler.kubeconfig \\
--bind-address=127.0.0.1"
EOF
- --kubeconfig :连接apiserver配置文件
- --leader-elect :当该组件启动多个时,自动选举(HA)。
5.6.2 生成kubeconfig文件
生成kube-scheduler证书 :
# 切换工作目录
cd ~/TLS/k8s
# 创建证书请求文件
cat > kube-scheduler-csr.json << EOF
{
"CN": "system:kube-scheduler",
"hosts": [],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"L": "BeiJing",
"ST": "BeiJing",
"O": "system:masters",
"OU": "System"
}
]
}
EOF
# 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-scheduler-csr.json | cfssljson -bare kube-scheduler
生成kubeconfig文件 :
KUBE_CONFIG="/opt/kubernetes/cfg/kube-scheduler.kubeconfig"
KUBE_APISERVER="https://192.168.242.51:6443"
kubectl config set-cluster kubernetes \
--certificate-authority=/opt/kubernetes/ssl/ca.pem \
--embed-certs=true \
--server=${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}
5.6.3 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
5.6.4 启动并设置开机启动
systemctl daemon-reload
systemctl start kube-scheduler
systemctl enable kube-scheduler
5.6.5 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://192.168.242.51:6443"
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=${KUBE_CONFIG}
通过kubectl工具查看当前集群组件状态 :
[root@k8s-master1 k8s]# kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME STATUS MESSAGE ERROR
scheduler Healthy ok
controller-manager Healthy ok
etcd-2 Healthy {"health":"true"}
etcd-0 Healthy {"health":"true"}
etcd-1 Healthy {"health":"true"}
如上说明Master节点组件运行正常。
5.6.6 授权kubelet-bootstrap用户允许请求证书
kubectl create clusterrolebinding kubelet-bootstrap \
--clusterrole=system:node-bootstrapper \
--user=kubelet-bootstrap
6、部署Work Node
下面还是在master node上面操作,即当Master节点,也当Work Node节点
6.1 创建工作目录并拷贝二进制文件
注: 在所有work node创建工作目录
mkdir -p /opt/kubernetes/{bin,cfg,ssl,logs}
从master节点k8s-server软件包中拷贝到所有work节点:
#进入到k8s-server软件包目录
cd /k8s-software/kubernetes/server/bin/
for i in {1..3}
do
scp kubelet kube-proxy root@192.168.242.5$i:/opt/kubernetes/bin/
done
6.2 部署kubelet
6.2.1 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=registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0"
EOF
- --hostname-override :显示名称,集群唯一(不可重复)。
- --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 :配置文件参数。
- --cert-dir :kubelet证书目录。
- --pod-infra-container-image :管理Pod网络容器的镜像 init container
6.2.2 配置文件
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
6.2.3 生成kubelet初次加入集群引导kubeconfig文件
KUBE_CONFIG="/opt/kubernetes/cfg/bootstrap.kubeconfig"
KUBE_APISERVER="https://192.168.242.51:6443" # apiserver IP:PORT
TOKEN="4136692876ad4b01bb9dd0988480ebba" # 与token.csv里保持一致 /opt/kubernetes/cfg/token.csv
# 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}
6.2.4 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
6.2.5 启动并设置开机启动
systemctl daemon-reload
systemctl start kubelet
systemctl enable kubelet
6.2.6 允许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-KbHieprZUMOvTFMHGQ1RNTZEhsSlT5X6wsh2lzfUry4 107s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending
#允许kubelet节点申请
[root@k8s-master1 bin]# kubectl certificate approve node-csr-KbHieprZUMOvTFMHGQ1RNTZEhsSlT5X6wsh2lzfUry4
certificatesigningrequest.certificates.k8s.io/node-csr-KbHieprZUMOvTFMHGQ1RNTZEhsSlT5X6wsh2lzfUry4 approved
#查看申请
[root@k8s-master1 bin]# kubectl get csr
NAME AGE SIGNERNAME REQUESTOR CONDITION
node-csr-KbHieprZUMOvTFMHGQ1RNTZEhsSlT5X6wsh2lzfUry4 2m35s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Approved,Issued
#查看节点
[root@k8s-master1 bin]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master1 NotReady <none> 2m11s v1.20.10
说明:
由于网络插件还没有部署,节点会没有准备就绪NotReady
6.3 部署kube-proxy
6.3.1 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
6.3.2 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
6.3.3 生成kube-proxy证书文件
# 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
6.3.4 生成kube-proxy.kubeconfig文件
KUBE_CONFIG="/opt/kubernetes/cfg/kube-proxy.kubeconfig"
KUBE_APISERVER="https://192.168.242.51:6443"
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=${KUBE_CONFIG}
6.3.5 systemd管理kube-proxy
cat > /usr/lib/systemd/system/kube-proxy.service << EOF
[Unit]
Description=Kubernetes Proxy
After=network.target
[Service]
EnvironmentFile=/opt/kubernetes/cfg/kube-proxy.conf
ExecStart=/opt/kubernetes/bin/kube-proxy \$KUBE_PROXY_OPTS
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF
6.3.6 启动并设置开机自启
systemctl daemon-reload
systemctl start kube-proxy
systemctl enable kube-proxy
6.4 部署网络组件(Calico)
Calico是一个纯三层的数据中心网络方案,是目前Kubernetes主流的网络方案。
kubectl apply -f calico.yaml
kubectl get pods -n kube-system
等Calico Pod都Running,节点也会准备就绪。
[root@k8s-master1 yaml]# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-97769f7c7-zcz5d 1/1 Running 0 3m11s
calico-node-5tnll 1/1 Running 0 3m11s
[root@k8s-master1 yaml]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready <none> 21m v1.20.10
6.5 授权apiserver访问kubelet
应用场景:如kubectl logs
cat > apiserver-to-kubelet-rbac.yaml << EOF
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
annotations:
rbac.authorization.kubernetes.io/autoupdate: "true"
labels:
kubernetes.io/bootstrapping: rbac-defaults
name: system:kube-apiserver-to-kubelet
rules:
- apiGroups:
- ""
resources:
- nodes/proxy
- nodes/stats
- nodes/log
- nodes/spec
- nodes/metrics
- pods/log
verbs:
- "*"
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: system:kube-apiserver
namespace: ""
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: system:kube-apiserver-to-kubelet
subjects:
- apiGroup: rbac.authorization.k8s.io
kind: User
name: kubernetes
EOF
kubectl apply -f apiserver-to-kubelet-rbac.yaml
7、新增加Work Node
7.1 拷贝以部署好的相关文件到新节点
在Master节点将Work Node涉及文件拷贝到新节点 242.52/242.53
for i in {2..3}; do scp -r /opt/kubernetes root@192.168.242.5$i:/opt/; done
for i in {2..3}; do scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service root@192.168.242.5$i:/usr/lib/systemd/system; done
for i in {2..3}; do scp -r /opt/kubernetes/ssl/ca.pem root@192.168.242.5$i:/opt/kubernetes/ssl/; done
7.2 删除kubelet证书和kubeconfig文件
rm -f /opt/kubernetes/cfg/kubelet.kubeconfig
rm -f /opt/kubernetes/ssl/kubelet*
说明:
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。
7.3 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
7.4 启动并设置开机自启
systemctl daemon-reload
systemctl start kubelet kube-proxy
systemctl enable kubelet kube-proxy
7.5 在Master上同意新的Node kubelet证书申请
#查看证书请求
[root@k8s-master1 kubernetes]# kubectl get csr
NAME AGE SIGNERNAME REQUESTOR CONDITION
node-csr-2vKShQc_wlqPrTPAwT5MHpdRWIX-oyr9NyBXu1XNwxg 12s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending
node-csr-KbHieprZUMOvTFMHGQ1RNTZEhsSlT5X6wsh2lzfUry4 47h kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Approved,Issued
#同意
[root@k8s-master1 kubernetes]# kubectl certificate approve node-csr-2vKShQc_wlqPrTPAwT5MHpdRWIX-oyr9NyBXu1XNwxg
certificatesigningrequest.certificates.k8s.io/node-csr-2vKShQc_wlqPrTPAwT5MHpdRWIX-oyr9NyBXu1XNwxg approved
7.6 查看Node状态(要稍等会才会变成ready,会下载一些初始化镜像)
[root@k8s-master1 kubernetes]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready <none> 46h v1.20.10
k8s-node1 Ready <none> 77s v1.20.10
说明:
其他节点同上
8、部署Dashboard和CoreDNS
8.1 部署Dashboard
kubectl apply -f kubernetes-dashboard.yaml
#查看部署情况
[root@k8s-master1 yaml]# kubectl get pods,svc -n kubernetes-dashboard
NAME READY STATUS RESTARTS AGE
pod/dashboard-metrics-scraper-7b59f7d4df-k49t9 1/1 Running 0 10m
pod/kubernetes-dashboard-74d688b6bc-l9jz4 1/1 Running 0 10m
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/dashboard-metrics-scraper ClusterIP 10.0.0.206 <none> 8000/TCP 10m
service/kubernetes-dashboard NodePort 10.0.0.10 <none> 443:30001/TCP 10m
访问地址: https://NodeIP:30001
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}')
使用输出的token登陆Dashboard(如访问提示https异常,可使用火狐浏览器)
8.2 部署CoreDNS
CoreDNS主要用于集群内部Service名称解析。
[root@k8s-master1 yaml]# kubectl apply -f coredns.yaml
[root@k8s-master1 yaml]# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-97769f7c7-zcz5d 1/1 Running 1 47h
calico-node-5tnll 1/1 Running 1 47h
calico-node-m8sdg 1/1 Running 0 42m
calico-node-pqvk9 1/1 Running 0 56m
coredns-6cc56c94bd-5hvfb 1/1 Running 0 37s
测试解析是否正常
[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.
/ # ns
nsenter nslookup
/ # nslookup kubernetes
Server: 10.0.0.2
Address 1: 10.0.0.2 kube-dns.kube-system.svc.cluster.local
至此一个单Master的k8s节点就已经完成了
9、增加Master节点(高可用架构)
说明:
Kubernetes作为容器集群系统,通过健康检查+重启策略实现了Pod故障自我修复能力,通过调度算法实现将Pod分布式部署,并保持预期副本数,根据Node失效状态自动在其他Node拉起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,所以Master高可用主要针对kube-apiserver组件,而该组件是以HTTP API提供服务,因此对他高可用与Web服务器类似,增加负载均衡器对其负载均衡即可,并且可水平扩容。
多Master架构图
9.1 部署Master2 Node
说明:
现在需要再增加一台新服务器,作为Master2 Node,IP是192.168.242.54。
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。
9.1.1 安装Docker(Master1)
scp /usr/bin/docker* root@192.168.242.54:/usr/bin
scp /usr/bin/runc root@192.168.242.54:/usr/bin
scp /usr/bin/containerd* root@192.168.242.54:/usr/bin
scp /usr/lib/systemd/system/docker.service root@192.168.242.54:/usr/lib/systemd/system
scp -r /etc/docker root@192.168.242.54:/etc
9.1.2 启动Docker、设置开机自启(Master2)
systemctl daemon-reload
systemctl start docker
systemctl enable docker
9.1.3 创建etcd证书目录(Master2)
mkdir -p /opt/etcd/ssl
9.1.4 拷贝文件(Master1)
拷贝Master1上所有k8s文件和etcd证书到Master2:
scp -r /opt/kubernetes root@192.168.242.54:/opt
scp -r /opt/etcd/ssl root@192.168.242.54:/opt/etcd
scp /usr/lib/systemd/system/kube* root@192.168.242.54:/usr/lib/systemd/system
scp /usr/bin/kubectl root@192.168.242.54:/usr/bin
scp -r ~/.kube root@192.168.242.54:~
9.1.5 删除证书(Master2)
删除kubelet和kubeconfig文件
rm -f /opt/kubernetes/cfg/kubelet.kubeconfig
rm -f /opt/kubernetes/ssl/kubelet*
9.1.6 修改配置文件和主机名(Master2)
修改apiserver、kubelet和kube-proxy配置文件为本地IP:
vi /opt/kubernetes/cfg/kube-apiserver.conf
...
--bind-address=192.168.242.54 \
--advertise-address=192.168.242.54 \
...
vi /opt/kubernetes/cfg/kube-controller-manager.kubeconfig
server: https://192.168.242.54:6443
vi /opt/kubernetes/cfg/kube-scheduler.kubeconfig
server: https://192.168.242.54:6443
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://192.168.242.54:6443
9.1.7 启动并设置开机自启(Master2)
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
9.1.7 查看集群状态(Master2)
kubectl get cs
NAME STATUS MESSAGE ERROR
scheduler Healthy ok
controller-manager Healthy ok
etcd-1 Healthy {"health":"true"}
etcd-2 Healthy {"health":"true"}
etcd-0 Healthy {"health":"true"}
9.1.8 审批kubelet证书申请
# 查看证书请求
[root@k8s-master1 ~]# kubectl get csr
NAME AGE SIGNERNAME REQUESTOR CONDITION
node-csr-EQoVFfTbo6DcvcWfaRzBbMst4BXmdyds99DEYk2oDDE 33m kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending
# 同意请求
kubectl certificate approve node-csr-EQoVFfTbo6DcvcWfaRzBbMst4BXmdyds99DEYk2oDDEcertificatesigningrequest.certificates.k8s.io/node-csr-EQoVFfTbo6DcvcWfaRzBbMst4BXmdyds99DEYk2oDDE approved
# 查看Node
[root@k8s-master1 ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready <none> 6d23h v1.20.10
k8s-master2 Ready <none> 9m11s v1.20.10
k8s-node1 Ready <none> 5d v1.20.10
k8s-node2 Ready <none> 5d v1.20.10
至此一个双Master节点k8s集群已经部署完毕
9.2 部署Nginx+Keepalived高可用负载均衡器
- 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一直可用,实现Nginx高可用。
- 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。
在两台Master节点操作。
9.2.1 安装软件包(Master1/Master2)
yum install epel-release -y
yum install nginx keepalived -y
9.2.2 Nginx配置文件(主备相同)
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 $upstream_bytes_sent';
access_log /var/log/nginx/k8s-access.log main;
upstream k8s-apiserver {
server 192.168.242.51:6443; # Master1 APISERVER IP:PORT
server 192.168.242.54:6443; # Master2 APISERVER IP:PORT
}
server {
listen 16443; # 由于nginx与master节点复用,这个监听端口不能是6443,否则会冲突
proxy_pass k8s-apiserver;
}
}
http {
log_format main '$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
9.2.3 keepalived配置文件(Master1)
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 {
192.168.242.55/24
}
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|$$")
if [ "$count" -eq 0 ];then
exit 1
else
exit 0
fi
EOF
chmod +x /etc/keepalived/check_nginx.sh
9.2.4 keepalived配置(master2)
cat > /etc/keepalived/keepalived.conf << EOF
global_defs {
notification_email {
acassen@firewall.loc
failover@firewall.loc
sysadmin@firewall.loc
}
notification_email_from Alexandre.Cassen@firewall.loc
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id NGINX_BACKUP
}
vrrp_script check_nginx {
script "/etc/keepalived/check_nginx.sh"
}
vrrp_instance VI_1 {
state BACKUP
interface ens33
virtual_router_id 51 # VRRP 路由 ID实例,每个实例是唯一的
priority 90
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.242.55/24
}
track_script {
check_nginx
}
}
EOF
准备上述配置文件中检查nginx运行状态的脚本:
cat > /etc/keepalived/check_nginx.sh << "EOF"
#!/bin/bash
count=$(ss -antp |grep 16443 |egrep -cv "grep|$$")
if [ "$count" -eq 0 ];then
exit 1
else
exit 0
fi
EOF
chmod +x /etc/keepalived/check_nginx.sh
说明:
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。
9.2.5 Nginx增加Steam模块
9.2.5.1 查看Nginx版本模块
如果已经安装 --with-stream模块,后面的步骤可以跳过
[root@k8s-master2 nginx-1.20.1]# nginx -V
nginx version: nginx/1.20.1
built by gcc 4.8.5 20150623 (Red Hat 4.8.5-44) (GCC)
configure arguments: --prefix=/usr/share/nginx --sbin-path=/usr/sbin/nginx --modules-path=/usr/lib64/nginx/modules --conf-path=/etc/nginx/nginx.conf --with-stream
9.2.5.2 下载同一个版本的nginx
下载地址 : http://nginx.org/download/
9.2.5.3 备份原Nginx文件
mv /usr/sbin/nginx /usr/sbin/nginx.bak
cp -r /etc/nginx{,.bak}
9.2.5.3 重新编译Nginx
检查模块是否支持,比如这次添加 limit 限流模块 和 stream 模块:
./configure –help | grep limit
ps:-without-http_limit_conn_module disable 表示已有该模块,编译时,不需要添加
./configure –help | grep stream
ps:–with-stream enable 表示不支持,编译时要自己添加该模块
根据第1步查到已有的模块,加上本次需新增的模块: --with-stream
编译环境准备
yum -y install libxml2 libxml2-dev libxslt-devel
yum -y install gd-devel
yum -y install perl-devel perl-ExtUtils-Embed
yum -y install GeoIP GeoIP-devel GeoIP-data
yum -y install pcre-devel
yum -y install openssl openssl-devel
yum -y install gcc make
编译
tar -xf nginx-1.20.1.tar.gz
cd nginx-1.20.1/
./configure --prefix=/usr/share/nginx --sbin-path=/usr/sbin/nginx --modules-path=/usr/lib64/nginx/modules --conf-path=/etc/nginx/nginx.conf --with-stream
make
说明:
make完成后不要继续输入“make install”,以免现在的nginx出现问题
以上完成后,会在objs目录下生成一个nginx文件,先验证:
[root@k8s-master2 nginx-1.20.1]# ./objs/nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
9.2.5.4 替换nginx到Master1/Master2
cp ./objs/nginx /usr/sbin/
scp objs/nginx root@192.168.242.51:/usr/sbin/
9.2.5.5 修改nginx服务文件
vim /usr/lib/systemd/system/nginx.service
[Unit]
Description=The nginx HTTP and reverse proxy server
After=network.target remote-fs.target nss-lookup.target
[Service]
Type=forking
PIDFile=/run/nginx.pid
ExecStartPre=/usr/bin/rm -rf /run/nginx.pid
ExecStartPre=/usr/sbin/nginx -t
ExecStart=/usr/sbin/nginx
ExecStop=/usr/sbin/nginx -s stop
ExecReload=/usr/sbin/nginx -s reload
PrivateTmp=true
[Install]
WantedBy=multi-user.target
9.2.6 启动并设置开机自启(master1/master2)
systemctl daemon-reload
systemctl start nginx keepalived
systemctl enable nginx keepalived
9.2.7 查看keepalived工作状态
[root@k8s-master1 ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:0c:29:40:1a:d8 brd ff:ff:ff:ff:ff:ff
inet 192.168.242.51/24 brd 192.168.242.255 scope global noprefixroute ens33
valid_lft forever preferred_lft forever
inet 192.168.242.55/24 scope global secondary ens33
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe40:1ad8/64 scope link
valid_lft forever preferred_lft forever
3: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default
link/ether 02:42:f3:e1:d2:e6 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0
valid_lft forever preferred_lft forever
4: tunl0@NONE: <NOARP,UP,LOWER_UP> mtu 1440 qdisc noqueue state UNKNOWN group default qlen 1000
link/ipip 0.0.0.0 brd 0.0.0.0
inet 10.244.159.128/32 brd 10.244.159.128 scope global tunl0
valid_lft forever preferred_lft forever
5: calia231fca418b@if4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1440 qdisc noqueue state UP group default
link/ether ee:ee:ee:ee:ee:ee brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet6 fe80::ecee:eeff:feee:eeee/64 scope lin
可以看到,在ens33网卡绑定了192.168.242.55 虚拟IP,说明工作正常。
9.2.8 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。
在Nginx Master执行 pkill nginx;
在Nginx Backup,ip addr命令查看已成功绑定VIP。
9.2.9 访问负载均衡器测试
找K8s集群中任意一个节点,使用curl查看K8s版本测试,使用VIP访问:
[root@k8s-master1 ~]# curl -k https://192.168.242.55:16443/version
{
"major": "1",
"minor": "20",
"gitVersion": "v1.20.10",
"gitCommit": "8152330a2b6ca3621196e62966ef761b8f5a61bb",
"gitTreeState": "clean",
"buildDate": "2021-08-11T18:00:37Z",
"goVersion": "go1.15.15",
"compiler": "gc",
"platform": "linux/amd64"
}[root@k8s-master1 ~]# curl -k https://192.168.242.55:16443/version
^[[A{
"major": "1",
"minor": "20",
"gitVersion": "v1.20.10",
"gitCommit": "8152330a2b6ca3621196e62966ef761b8f5a61bb",
"gitTreeState": "clean",
"buildDate": "2021-08-11T18:00:37Z",
"goVersion": "go1.15.15",
"compiler": "gc",
"platform": "linux/amd64"
}[root@k8s-master1 ~]# curl -k https://192.168.242.55:16443/version
{
"major": "1",
"minor": "20",
"gitVersion": "v1.20.10",
"gitCommit": "8152330a2b6ca3621196e62966ef761b8f5a61bb",
"gitTreeState": "clean",
"buildDate": "2021-08-11T18:00:37Z",
"goVersion": "go1.15.15",
"compiler": "gc",
"platform": "linux/amd64"
}[root@k8s-master1 ~]# curl -k https://192.168.242.55:16443/version
{
"major": "1",
"minor": "20",
"gitVersion": "v1.20.10",
"gitCommit": "8152330a2b6ca3621196e62966ef761b8f5a61bb",
"gitTreeState": "clean",
"buildDate": "2021-08-11T18:00:37Z",
"goVersion": "go1.15.15",
"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-master1 ~]# tailf /var/log/nginx/k8s-access.log
192.168.242.51 192.168.242.51:6443 - [14/Sep/2021:23:53:07 +0800] 200 424
192.168.242.51 192.168.242.54:6443 - [14/Sep/2021:23:53:09 +0800] 200 424
192.168.242.51 192.168.242.51:6443 - [14/Sep/2021:23:53:10 +0800] 200 424
192.168.242.51 192.168.242.54:6443 - [14/Sep/2021:23:53:11 +0800] 200 424
9.3 修改所有的Work 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192.168.242.51修改为192.168.242.55(VIP)。
在所有Worker Node执行:
sed -i 's#192.168.242.51:6443#192.168.242.55:16443#' /opt/kubernetes/cfg/*
systemctl restart kubelet kube-proxy
检查节点状态
[root@k8s-master1 ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready <none> 7d v1.20.10
k8s-master2 Ready <none> 90m v1.20.10
k8s-node1 Ready <none> 5d1h v1.20.10
k8s-node2 Ready <none> 5d1h v1.20.10
至此,一套高可用的k8s二进制可用集群就部署完成了~
三、部署常见问题
1、系统断电后,某个etcd节点无法启动
1.1 报错信息
publish error: etcdserver: request timed out
1.2 解决方法(如果没有重要数据,或者刚进行完初始化)
检查日志发现并没有特别明显的错误,根据经验来讲,etcd 节点坏掉一个其实对集群没有大的影响,这时集群已经可以正常使用了,但是这个坏掉的 etcd 节点并没有启动
#进入 etcd 的数据存储目录进行备份 备份原有数据:
cd /var/lib/etcd/default.etcd/member/
cp * /data/bak/
#删除这个目录下的所有数据文件
rm -rf /var/lib/etcd/default.etcd/member/*
#停止另外两台 etcd 节点,因为 etcd 节点启动时需要所有节点一起启动,启动成功后即可使用。
systemctl stop etcd
systemctl restart etcd