k8s二进制安装(迅速部署)
k8s 二进制部署
改文章转自k8s1.20环境搭建部署(二进制版本) - 小家电维修 - 博客园并对其进行了一些添加及修改并附加了网络相关插件的安装
1.1 生产环境部署K8s集群的
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。
二进制包
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。
1.2 环境信息
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需求,如果服务器不能上网,需要提前下载对应镜像并导入节点
软件 | 版本 |
linux | Centos 7.9.2009 |
Kubernetes | 1.20.7 |
Docker | 20.10.7 |
Etcd | 3.4.9 |
Calico | 3.19.1 |
角色 | IP | 组件 | 主机名 |
Master01 Load Balancer(Master) | 172.21.161.110 172.21.161.120(vip) | kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy Nginx L4 | master01 |
Master02 Load Balancer(Backup) | 172.21.161.111 | kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy Nginx L4 | master02 |
etcd01 | 172.21.161.112 | etcd | etcd01 |
etcd02 | 172.21.161.113 | etcd | etcd02 |
etcd03 | 172.21.161.114 | etcd | etcd03 |
Node01 | 172.21.161.115 | kubelet kube-proxy docker flannel | node01 |
Node02 | 172.21.161.116 | kubelet kube-proxy docker flannel | node02 |
public | 172.21.161.149 | 跳板机 | public |
这里为了使搭建过程更清晰,尽量将各角色分配到不同的机器上。每个机器都部署属于自己的角色。比如生成证书就在public跳板机上去生成,然后推送到对应服务器。
1.3 拓扑信息
单Master架构图
单Master服务器规划:
角色 | IP | 组件 | 主机名 |
Master01 | 172.21.161.110 | kube-apiserver kube-controller-manager kube-scheduler | master01 |
etcd01 | 172.21.161.112 | etcd | etcd01 |
etcd02 | 172.21.161.113 | etcd | etcd02 |
etcd03 | 172.21.161.114 | etcd | etcd03 |
Node01 | 172.21.161.115 | kubelet kube-proxy docker | node01 |
Node02 | 172.21.161.116 | kubelet kube-proxy docker | node02 |
public | 172.21.161.149 | 跳板机 | public |
1.4 操作系统初始化设置
# 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> # 在需要的主机添加hosts,这里一定要是追加,否则覆盖了默认的记录,在Calico和许多服务会出现问题 cat >> /etc/hosts << EOF 172.21.161.110 master01 172.21.161.111 master02 172.21.161.115 node01 172.21.161.116 node02 172.21.161.112 etcd01 172.21.161.113 etcd02 172.21.161.114 etcd03 172.21.161.149 public 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 yum install ntpdate chrony -y ntpdate time.windows.com
2.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。
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。
找一台服务器操作,这里用public节点。证书的生成以及分配都在public上操作
#public节点操作 mkdir -p /k8s-deploy/cfssl/ cd /k8s-deploy/cfssl 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
为什么需要证书?
K8s所有组件采用https加密通信,这些组件一般由两套根证书生成:K8S组件(apiserver)和Etcd。
按照需求分类来说,这里所有的服务组件controller-manager、scheduler、kubelet、kube-proxy、kubeclt等需要访问apiserver,这里需要一套。Apiserver访问etcd集群又是一套单独的。所以这里2套证书是2个不同自签CA颁发的。
2.2 生成Etcd证书
1.自签证书颁发机构(CA)
签发证书都在public机器上。
创建工作目录:
#public节点操作 mkdir -p /k8s-deploy/cfssl/TLS/{etcd,k8s} cd /k8s-deploy/cfssl/TLS/etcd
自签CA:
#public节点操作 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": "ShangHai", "ST": "ShangHai" } ] } EOF
生成证书:
cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
会生成ca.pem和ca-key.pem文件
2.使用自签CA签发Etcd HTTPS证书
创建证书申请文件:
#public节点操作 cat > server-csr.json << EOF { "CN": "etcd", "hosts": [ "172.21.161.112", "172.21.161.113", "172.21.161.114" ], "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "L": "ShangHai", "ST": "ShangHai" } ] } EOF
注意: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。
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
会生成server.pem和server-key.pem文件。
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etcd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.创建工作目录并解压二进制包
#etcd01节点操作 mkdir /opt/etcd/{bin,cfg,ssl} -p tar zxvf etcd-v3.4.9-linux-amd64.tar.gz mv etcd-v3.4.9-linux-amd64/{etcd,etcdctl} /opt/etcd/bin/
2.创建etcd配置文件
#etcd01节点操作 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://172.21.161.112:2380" ETCD_LISTEN_CLIENT_URLS="https://172.21.161.112:2379" #[Clustering] ETCD_INITIAL_ADVERTISE_PEER_URLS="https://172.21.161.112:2380" ETCD_ADVERTISE_CLIENT_URLS="https://172.21.161.112:2379" ETCD_INITIAL_CLUSTER="etcd-1=https://172.21.161.112:2380,etcd-2=https://172.21.161.113:2380,etcd-3=https://172.21.161.114:2380" ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster" ETCD_INITIAL_CLUSTER_STATE="new" EOF
- ETCD_NAME:节点名称,集群中唯一
- ETCD_DATA_DIR:数据目录
- ETCD_LISTEN_PEER_URLS:集群通信监听地址
- ETCD_LISTEN_CLIENT_URLS:客户端访问监听地址
- ETCD_INITIAL_ADVERTISE_PEERURLS:集群通告地址
- ETCD_ADVERTISE_CLIENT_URLS:客户端通告地址
- ETCD_INITIAL_CLUSTER:集群节点地址
- ETCD_INITIALCLUSTER_TOKEN:集群Token
- ETCD_INITIALCLUSTER_STATE:加入集群的当前状态,new是新集群,existing表示加入已有集群
3.systemd管理etcd
#etcd01节点操作 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
在public上把刚才生成的证书拷贝到etcd01配置文件中的路径:(只有这里是在public上操作,其余都是在etc01上操作)
[root@public etcd]# scp -r /k8s-deploy/cfssl/TLS/etcd/ca*pem /k8s-deploy/cfssl/TLS/etcd/server*pem root@etcd01:/opt/etcd/ssl
5.启动并设置开机启动
#etcd01节点操作 systemctl daemon-reload #启动的时候会hold住,因为其它两个节点没有配置,一直在寻找其它节点 systemctl start etcd systemctl enable etcd
6.将上面节点1所有生成的文件拷贝到节点2和节点3
#etcd01节点操作 scp -r /opt/etcd/ root@etcd02:/opt/ scp /usr/lib/systemd/system/etcd.service root@etcd02:/usr/lib/systemd/system/ scp -r /opt/etcd/ root@etcd03:/opt/ scp /usr/lib/systemd/system/etcd.service root@etcd03:/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:(总共5处)
vi /opt/etcd/cfg/etcd.conf #[Member] ETCD_NAME="etcd-1" # 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://172.21.161.112:2380" # 修改此处为当前服务器IP ETCD_LISTEN_CLIENT_URLS="https:// 172.21.161.112:2379" # 修改此处为当前服务器IP #[Clustering] ETCD_INITIAL_ADVERTISE_PEER_URLS="https:// 172.21.161.112:2380" # 修改此处为当前服务器IP ETCD_ADVERTISE_CLIENT_URLS="https:// 172.21.161.112:2379" # 修改此处为当前服务器IP ETCD_INITIAL_CLUSTER="etcd-1=https://172.21.161.112:2380,etcd-2=https://172.21.161.113:2380,etcd-3=https://172.21.161.114:2380" ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster" ETCD_INITIAL_CLUSTER_STATE="new"
最后启动etcd并设置开机启动,同上。
7.查看集群状态
[root@etcd01 bin]# 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://172.21.161.112:2379,https://172.21.161.113:2379,https://172.21.161.114:2379" endpoint health --write-out=table +-----------------------------+--------+-------------+-------+ | ENDPOINT | HEALTH | TOOK | ERROR | +-----------------------------+--------+-------------+-------+ | https://172.21.161.112:2379 | true | 50.191672ms | | | https://172.21.161.113:2379 | true | 52.394036ms | | | https://172.21.161.114:2379 | true | 46.009422ms | | +-----------------------------+--------+-------------+-------+
如果有问题查看日志:/var/log/message或者journalctl -f -u etcd
3.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-20.10.7.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。本节其实已经用yum安装一遍了,这里只是做一个源码的演示。
3.1 解压二进制包
tar zxvf docker-20.10.7.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
4.部署Master
4.1 生成kube-apiserver证书
1.自签证书颁发机构(CA)
证书操作在public机器上,这是另一套独立etcd的自签ca证书
# 切换工作目录(public) cd /k8s-deploy/cfssl/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": "ShangHai", "ST": "ShangHai", "O": "k8s", "OU": "System" } ] } EOF
生成证书:
cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
会生成ca.pem和ca-key.pem文件。
2.使用自签CA签发kube-apiserver HTTPS证书
创建证书申请文件:
#public节点操作 cat > server-csr.json << EOF { "CN": "kubernetes", "hosts": [ "10.0.0.1", "127.0.0.1", "172.21.161.110", "172.21.161.111", "172.21.161.120", "kubernetes", "kubernetes.default", "kubernetes.default.svc", "kubernetes.default.svc.cluster", "kubernetes.default.svc.cluster.local" ], "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "L": "ShangHai", "ST": "ShangHai", "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
会生成server.pem和server-key.pem文件。
4.2 从Github下载二进制文件
下载地址: 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。
4.3 解压二进制包
#master01节点操作 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/
4.4 部署kube-apiserver
1.创建配置文件
#master01节点操作 cat > /opt/kubernetes/cfg/kube-apiserver.conf << EOF KUBE_APISERVER_OPTS="--logtostderr=false \\ --v=2 \\ --log-dir=/opt/kubernetes/logs \\ --etcd-servers=https://172.21.161.112:2379,https://172.21.161.113:2379,https://172.21.161.114:2379 \\ --bind-address=172.21.161.110 \\ --secure-port=6443 \\ --advertise-address=172.21.161.110 \\ --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\\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
2.拷贝刚才生成的证书(public)
把刚才生成的证书拷贝到配置文件中的路径:
[root@public k8s]#scp -r /k8s-deploy/cfssl/TLS/k8s/ca*pem /k8s-deploy/cfssl/TLS/k8s/server*pem root@master01:/opt/kubernetes/ssl
注意,因为etcd和master不在一台机器部署,这里etcd的证书也要拷贝
#首先master01要创建目录mkdir /opt/etcd/ssl -p [root@master01 bin]# mkdir /opt/etcd/ssl -p [root@public k8s]# scp -r /k8s-deploy/cfssl/TLS/etcd/ca*pem /k8s-deploy/cfssl/TLS/etcd/server*pem root@master01:/opt/etcd/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。
TLS bootstraping 工作流程:
创建上述配置文件中token文件:
#master01节点操作 cat > /opt/kubernetes/cfg/token.csv << EOF c47ffb939f5ca36231d9e3121a252940,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 ' '
4.systemd管理apiserver
#master01节点操作 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
#master01节点操作 systemctl daemon-reload systemctl start kube-apiserver systemctl enable kube-apiserver
启动会有异常,这里不影响运行及后续操作,可以忽略,具体解决办法参考以下链接
https://github.com/kubernetes/kubernetes/issues/76956
4.5 部署kube-controller-manager
1.创建配置文件
#master01节点操作 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证书以及配置文件
生成kube-controller-manager证书:(public)
# 切换工作目录(public,证书一般要切换回public机器操作) cd /k8s-deploy/cfssl/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": "ShangHai", "ST": "ShangHai", "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):
这里生成的证书文件因为在public,所以要拷贝到master01的相应目录
[root@public k8s]# scp -r /k8s-deploy/cfssl/TLS/k8s/kube-controller-manager*pem root@master01:/opt/kubernetes/ssl
#master01节点操作 KUBE_CONFIG="/opt/kubernetes/cfg/kube-controller-manager.kubeconfig" KUBE_APISERVER="https://172.21.161.110:6443" kubectl config set-cluster kubernetes \ --certificate-authority=/opt/kubernetes/ssl/ca.pem \ --embed-certs=true \ --server=${KUBE_APISERVER} \ --kubeconfig=${KUBE_CONFIG} kubectl config set-credentials kube-controller-manager \ --client-certificate=/opt/kubernetes/ssl/kube-controller-manager.pem \ --client-key=/opt/kubernetes/ssl/kube-controller-manager-key.pem \ --embed-certs=true \ --kubeconfig=${KUBE_CONFIG} kubectl config set-context default \ --cluster=kubernetes \ --user=kube-controller-manager \ --kubeconfig=${KUBE_CONFIG} kubectl config use-context default --kubeconfig=${KUBE_CONFIG} #这里配置文件就不展示了
3.systemd管理controller-manager
#master01节点操作 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
#master01节点操作 systemctl daemon-reload systemctl start kube-controller-manager systemctl enable kube-controller-manager
5.可能出现的问题
对后续不影响,时间充裕的可以尝试排错。
4.6 部署kube-scheduler
1.创建配置文件
#master01节点操作 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证书以及配置文件
生成kube-scheduler证书:
# 切换工作目录(public,证书一般要切换回public机器操作) cd /k8s-deploy/cfssl/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": "ShangHai", "ST": "ShangHai", "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(以下是shell命令,直接在终端执行):
这里生成的证书文件因为在public,所以要拷贝到master01的相应目录
[root@public k8s]# scp -r /k8s-deploy/cfssl/TLS/k8s/kube-scheduler*pem root@master01:/opt/kubernetes/ssl
#master01节点操作 KUBE_CONFIG="/opt/kubernetes/cfg/kube-scheduler.kubeconfig" KUBE_APISERVER="https://172.21.161.110:6443" 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=/opt/kubernetes/ssl/kube-scheduler.pem \ --client-key=/opt/kubernetes/ssl/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=${KUBE_CONFIG}
3.systemd管理scheduler
#master01节点操作 cat > /usr/lib/systemd/system/kube-scheduler.service << EOF [Unit] Description=Kubernetes Scheduler Documentation=https://github.com/kubernetes/kubernetes [Service] EnvironmentFile=/opt/kubernetes/cfg/kube-scheduler.conf ExecStart=/opt/kubernetes/bin/kube-scheduler \$KUBE_SCHEDULER_OPTS Restart=on-failure [Install] WantedBy=multi-user.target EOF
4.启动并设置开机启动
#master01节点操作 systemctl daemon-reload systemctl start kube-scheduler systemctl enable kube-scheduler
出现以下问题的,重头开始做吧
4.7 查看集群状态(public)
生成kubectl连接集群的证书:
#想访问k8s集群的机器操作,这里使用public cat > admin-csr.json <<EOF { "CN": "admin", "hosts": [], "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "L": "ShangHai", "ST": "ShangHai", "O": "system:masters", "OU": "System" } ] } EOF cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes admin-csr.json | cfssljson -bare admin
生成kubeconfig文件:
mkdir /root/.kube KUBE_CONFIG="/root/.kube/config" KUBE_APISERVER="https://172.21.161.110:6443" kubectl config set-cluster kubernetes \ --certificate-authority=/k8s-deploy/cfssl/TLS/k8s/ca.pem \ --embed-certs=true \ --server=${KUBE_APISERVER} \ --kubeconfig=${KUBE_CONFIG} kubectl config set-credentials cluster-admin \ --client-certificate=/k8s-deploy/cfssl/TLS/k8s/admin.pem \ --client-key=/k8s-deploy/cfssl/TLS/k8s/admin-key.pem \ --embed-certs=true \ --kubeconfig=${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:
kubectl get cs NAME STATUS MESSAGE ERROR scheduler Healthy ok controller-manager Healthy ok etcd-2 Healthy {"health":"true"} etcd-1 Healthy {"health":"true"} etcd-0 Healthy {"health":"true"}
如上输出说明Master节点组件运行正常。
也可以顺便同时让master可以访问,在public将config文件拷贝至master01节点即可
[root@master01 ssl]# mkdir /root/.kube [root@public ~]# scp -r /root/.kube/ root@master01:/root
4.8 授权kubelet-bootstrap用户允许请求证书
#创建node必备,不然node的kubelet无法启动,就是创建一个可以申请证书的用户 kubectl create clusterrolebinding kubelet-bootstrap \ --clusterrole=system:node-bootstrapper \ --user=kubelet-bootstrap
5.部署Worker Node
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至node节点:
cd /tools/kubernetes/server/bin/ scp -r kubelet kube-proxy root@node01:/opt/kubernetes/bin/ scp /opt/kubernetes/ssl/ca.pem root@node01:/opt/kubernetes/ssl/ scp /usr/bin/kubectl node01:/usr/bin
5.2 部署kubelet
1.创建配置文件
#node01节点操作 cat > /opt/kubernetes/cfg/kubelet.conf << EOF KUBELET_OPTS="--logtostderr=false \\ --v=2 \\ --log-dir=/opt/kubernetes/logs \\ --hostname-override=node01 \\ --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=lizexiong/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
如果主机名在通过master审批之后更改了,或者是什么原因更改了,node就会出现下面的错误提示
2.配置参数文件
#node01节点操作 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
#node01节点操作 KUBE_CONFIG="/opt/kubernetes/cfg/bootstrap.kubeconfig" KUBE_APISERVER="https://172.21.161.110:6443" # apiserver IP:PORT TOKEN="c47ffb939f5ca36231d9e3121a252940" # 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.systemd管理kubelet
#node01节点操作 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
#node01节点操作 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@public k8s]# kubectl get csr NAME AGE SIGNERNAME REQUESTOR CONDITION node-csr-84G21oPC3hDbyMwZN62ExQDI4D2Xa8IO74zHtlWRhD8 60s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending # 批准申请 [root@public k8s]# kubectl certificate approve node-csr-84G21oPC3hDbyMwZN62ExQDI4D2Xa8IO74zHtlWRhD8 certificatesigningrequest.certificates.k8s.io/node-csr-84G21oPC3hDbyMwZN62ExQDI4D2Xa8IO74zHtlWRhD8 approved [root@public k8s]# kubectl get node NAME STATUS ROLES AGE VERSION node01 NotReady <none> 3s v1.20.7 #这个时候节点状态肯定是NotReady,安装Calico之后就会好
注意:可能出现的报错
[root@public k8s]# kubectl certificate approve node-csr-84G21oPC3hDbyMwZN62ExQDI4D2Xa8IO74zHtlWRhD8 No resources found error: no kind "CertificateSigningRequest" is registered for version "certificates.k8s.io/v1" in scheme "k8s.io/kubernetes/pkg/kubectl/scheme/scheme.go:28" #因为客户端版本不对 [root@public k8s]# kubectl version --short Client Version: v1.12.7 Server Version: v1.20.7
注:由于网络插件还没有部署,节点会没有准备就绪 NotReady
5.4 部署kube-proxy
1.创建配置文件
#node01节点操作 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
#node01节点操作 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: node01 clusterCIDR: 10.0.0.0/24 EOF
3.生成kube-proxy.kubeconfig文件
# 切换工作目录(public) cd /k8s-deploy/cfssl/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": "ShangHai", "ST": "ShangHai", "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 #将证书从public拷贝至node [root@public k8s]# scp /k8s-deploy/cfssl/TLS/k8s/kube-proxy*pem root@node01:/opt/kubernetes/ssl
#node01节点操作 #生成kubeconfig文件: KUBE_CONFIG="/opt/kubernetes/cfg/kube-proxy.kubeconfig" KUBE_APISERVER="https://172.21.161.110:6443" 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=/opt/kubernetes/ssl/kube-proxy.pem \ --client-key=/opt/kubernetes/ssl/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
#node01节点操作 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
#node01节点操作 systemctl daemon-reload systemctl start kube-proxy systemctl enable kube-proxy
启动后会有报错,只有在calico插件安装完成后才会正常。
5.5 部署网络组件
Calico是一个纯三层的数据中心网络方案,是目前Kubernetes主流的网络方案。
下载地址: https://docs.projectcalico.org/getting-started/kubernetes/self-managed-onprem/onpremises
部署Calico:
#哪里有yaml文件可以访问集群,就在哪里操作 curl https://docs.projectcalico.org/manifests/calico.yaml -O kubectl apply -f calico.yaml kubectl get pods -n kube-system
等Calico Pod都Running,节点也会准备就绪:(镜像在国外,可能会有些慢)
kubectl get node NAME STATUS ROLES AGE VERSION node01 Ready <none> 37m v1.20.7
注意:这里有个问题需要注意
准备环境的时候,各node节点的/etc/hosts里面的默认记录,也就是localhost记录,一定不要删除或者误删,否则会出现以下报错,pod是运行的,但是健康检查一直无法通过。
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
5.7 新增加Worker Node
1.拷贝已部署好的Node相关文件到新节点
[root@node01 cfg]# scp -r /opt/kubernetes/ root@node02:/opt #包括,程序,证书,都在里面,主要需要ca.pem [root@node01 cfg]# scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service root@node02:/usr/lib/systemd/system
2.删除kubelet证书和kubeconfig文件
#node02节点操作 rm -f /opt/kubernetes/cfg/kubelet.kubeconfig #审批通过后会自动生成 rm -f /opt/kubernetes/ssl/kubelet-client*
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
#node02节点操作 vi /opt/kubernetes/cfg/kubelet.conf --hostname-override=node01 #修改成真实主机名 vi /opt/kubernetes/cfg/kube-proxy-config.yml hostnameOverride: node01 #修改成真实主机名
4.启动并设置开机启动
#node02节点操作 systemctl daemon-reload systemctl start kubelet kube-proxy systemctl enable kubelet kube-proxy
5.在Master上批准新Node kubelet证书申请
# 查看证书请求 kubectl get csr NAME AGE SIGNERNAME REQUESTOR CONDITION node-csr-4zTjsaVSrhuyhIGqsefxzVoZDCNKei-aE2jyTP81Uro 89s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending # 授权请求 kubectl certificate approve node-csr-4zTjsaVSrhuyhIGqsefxzVoZDCNKei-aE2jyTP81Uro
6.查看Node状态
kubectl get node NAME STATUS ROLES AGE VERSION node01 Ready <none> 47m v1.20.7 node02 Ready <none> 6m49s v1.20.7
6.部署Dashboard和CoreDNS
6.1 部署Dashboard
github上面选版本 Releases · kubernetes/dashboard · GitHub kubectl apply -f kubernetes-dashboard.yaml # 查看部署 kubectl get pods,svc -n kubernetes-dashboard
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登录Dashboard。
6.2 部署CoreDNS
CoreDNS用于集群内部Service名称解析。
https://github.com/coredns/deployment/tree/master/kubernetes
coredns.yaml.sed deploy.sh
./deploy.sh $your_IP > coredns.yaml
#哪里有yaml文件可以访问集群,就在哪里操作 kubectl apply -f coredns.yaml kubectl get pods -n kube-system NAME READY STATUS RESTARTS AGE coredns-5ffbfd976d-j6shb 1/1 Running 0 32s
DNS解析测试:
#创建之前要开启api访问kubelet权限,不然无法进入容器 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
解析没问题。
至此一个单Master集群就搭建完成了!这个环境就足以满足学习实验了,下面继续扩容多Master集群!
7.扩容多Master(高可用架构)
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:
7.1 部署Master2
现在需要再增加一台新服务器,作为Master2 Node,IP是172.21.161.111。
为了节省资源你也可以将之前部署好的Worker Node1复用为Master2 Node角色(即部署Master组件,这里不这么做)
Master02 与已部署的Master01所有操作一致。所以我们只需将Master01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.准备工作
安装docker及更改主机名以及主机名加入到所有机器的映射
2.创建etcd证书目录
在Master02创建etcd证书目录:
#master02节点操作 mkdir -p /opt/etcd/ssl
3.拷贝文件(Master01操作)
拷贝Master1上所有K8s文件和etcd证书到Master2:
scp -r /opt/kubernetes root@master02:/opt scp -r /opt/etcd/ssl root@master02:/opt/etcd scp /usr/lib/systemd/system/kube* root@master02:/usr/lib/systemd/system scp /usr/bin/kubectl root@master02:/usr/bin scp -r /root/.kube root@master02:/root
4.删除证书文件
删除kubelet证书和kubeconfig文件:
#master02节点操作 #如果master没有部署node节点组件,可忽略这一步 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: (7处修改)
#master02节点操作 vi /opt/kubernetes/cfg/kube-apiserver.conf ... --bind-address=172.21.161.111 \ --advertise-address=172.21.161.111 \ ... vi /opt/kubernetes/cfg/kube-controller-manager.kubeconfig server: https:// 172.21.161.111:6443 vi /opt/kubernetes/cfg/kube-scheduler.kubeconfig server: https:// 172.21.161.111:6443 vi root/.kube/config server: https://172.21.161.111:6443 #下面的2处无视,因为目前master节点还没部署node组件 vi /opt/kubernetes/cfg/kubelet.conf --hostname-override=master02 vi /opt/kubernetes/cfg/kube-proxy-config.yml hostnameOverride: master02
6.启动设置开机启动
#master02节点操作 systemctl daemon-reload systemctl start kube-apiserver kube-controller-manager kube-scheduler systemctl enable kube-apiserver kube-controller-manager kube-scheduler
7.查看集群状态
#master02节点操作 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"}
7.2 部署Nginx+Keepalived高可用负载均衡器
kube-apiserver高可用架构图:
- 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。
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。
在两台Master节点操作。
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/备一样)
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 $upstream_bytes_sent'; access_log /var/log/nginx/k8s-access.log main; upstream k8s-apiserver { server 172.21.161.110:6443; # Master1 APISERVER IP:PORT server 172.21.161.111:6443; # Master2 APISERVER IP:PORT } server { listen 16443; # 由于nginx与master节点复用,这个监听端口不能是6443,否则会冲突 proxy_pass k8s-apiserver; } } http { log_format main '$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(Nginx Master)
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 ens192 # 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 { 172.21.161.120/24 } 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|$$") if [ "$count" -eq 0 ];then exit 1 else exit 0 fi EOF chmod +x /etc/keepalived/check_nginx.sh
注:keepalived根据脚本返回状态码(0为工作正常,非0不正常)判断是否故障转移。
4.keepalived配置文件(Nginx Backup)
cat > /etc/keepalived/keepalived.conf << EOF global_defs { notification_email { acassen@firewall.loc failover@firewall.loc sysadmin@firewall.loc } notification_email_from Alexandre.Cassen@firewall.loc smtp_server 127.0.0.1 smtp_connect_timeout 30 router_id NGINX_BACKUP } vrrp_script check_nginx { script "/etc/keepalived/check_nginx.sh" } vrrp_instance VI_1 { state BACKUP interface ens192 virtual_router_id 51 # VRRP 路由 ID实例,每个实例是唯一的 priority 90 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 172.21.161.120/24 } track_script { check_nginx } } EOF
准备上述配置文件中检查nginx运行状态的脚本
cat > /etc/keepalived/check_nginx.sh << "EOF" #!/bin/bash count=$(ss -antp |grep 16443 |egrep -cv "grep|$$") 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
6.查看keepalived工作状态
[root@master01 .kube]# 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: ens192: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000 link/ether 00:50:56:ba:aa:a6 brd ff:ff:ff:ff:ff:ff inet 172.21.161.110/24 brd 172.21.161.255 scope global noprefixroute ens192 valid_lft forever preferred_lft forever inet 172.21.161.120/24 scope global secondary ens192 valid_lft forever preferred_lft forever inet6 fe80::da18:1a5c:9b1c:9a6f/64 scope link noprefixroute valid_lft forever preferred_lft forever 3: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default link/ether 02:42:1e:19:9d:59 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 可以看到,在ens192网卡绑定了172.21.161.120 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。
在Nginx Master执行 pkill nginx;
在Nginx Backup,ip addr命令查看已成功绑定VIP
8.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@public ~]# curl -k https://172.21.161.120:16443/version { "major": "1", "minor": "20", "gitVersion": "v1.20.7", "gitCommit": "132a687512d7fb058d0f5890f07d4121b3f0a2e2", "gitTreeState": "clean", "buildDate": "2021-05-12T12:32:49Z", "goVersion": "go1.15.12", "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@master01 .kube]# tail -f /var/log/nginx/k8s-access.log 172.21.161.110 172.21.161.110:6443 - [13/Jun/2021:11:56:31 +0800] 200 2138 172.21.161.110 172.21.161.111:6443 - [13/Jun/2021:12:01:37 +0800] 200 1711 172.21.161.115 172.21.161.110:6443 - [13/Jun/2021:19:04:08 +0800] 200 1172 172.21.161.115 172.21.161.111:6443 - [13/Jun/2021:19:05:39 +0800] 200 3596 172.21.161.116 172.21.161.110:6443 - [13/Jun/2021:19:06:22 +0800] 200 1173 172.21.161.116 172.21.161.110:6443 - [13/Jun/2021:19:06:28 +0800] 200 1174 172.21.161.116 172.21.161.111:6443 - [13/Jun/2021:19:07:59 +0800] 200 3020
到此还没结束,还有下面最关键的一步。
7.3 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Master01 ,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172.21.161.110修改为172.21.161.120(VIP)。
在所有Worker Node执行:
sed -i 's#172.21.161.110:6443#172.21.161.120:16443#' /opt/kubernetes/cfg/*
准确来说,上述命令只适合在纯node节点上使用,如果master01部署了node,那么也会有上述IP,所以为了更精确,下面指出具体哪几个配置文件需要更改。
[root@node01 cfg]# grep 172.21.161.120 /opt/kubernetes/cfg/* /opt/kubernetes/cfg/bootstrap.kubeconfig: server: https://172.21.161.120:16443 /opt/kubernetes/cfg/kubelet.kubeconfig: server: https://172.21.161.120:16443 /opt/kubernetes/cfg/kube-proxy.kubeconfig: server: https://172.21.161.120:16443
当然/root/.kube/config里面也需要修改。
最后将服务重启
systemctl restart kubelet kube-proxy
8.将Master增加worker node节点
当然,在一般情况下,master上也有kubelet等一些进行,用来部署一些系统级别pod,但是前面为了让部署的步骤拆分的更为细致,所以,每台机器部署不同的角色,这里将Master上增加worker组件。和新增一台worker node区别不大。
1.拷贝已部署好的Node相关文件到新节点
在node节点将Worker Node涉及文件拷贝到master01
#node01节点操作 scp -r /opt/kubernetes/ root@master01:/opt scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service root@master01:/usr/lib/systemd/system
2.删除kubelet证书和kubeconfig文件
rm -rf /opt/kubernetes/cfg/kubelet.kubeconfig rm -rf /opt/kubernetes/ssl/kubelet-client-*
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=master01 vi /opt/kubernetes/cfg/kube-proxy-config.yml hostnameOverride: master01
4.启动并设置开机启动
systemctl daemon-reload systemctl start kubelet kube-proxy systemctl enable kubelet kube-proxy
5.在Master上批准新Node kubelet证书申请
# 查看证书请求 kubectl get csr NAME AGE SIGNERNAME REQUESTOR CONDITION node-csr-4zTjsaVSrhuyhIGqsefxzVoZDCNKei-aE2jyTP81Uro 89s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending # 授权请求 kubectl certificate approve node-csr-4zTjsaVSrhuyhIGqsefxzVoZDCNKei-aE2jyTP81Uro
6.查看Node状态
[root@public ~]# kubectl get node NAME STATUS ROLES AGE VERSION master01 Ready <none> 4h37m v1.20.7 master02 Ready <none> 4h32m v1.20.7 node01 Ready <none> 15h v1.20.7 node02 Ready <none> 15h v1.20.7
多台master也一样
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