【k8s】集群搭建篇
文章目录
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- 搭建kubernetes集群
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- kubeadm
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- 初始化操作
- 安装软件(master、所有node节点)
- Kubernetes Master初始化
- Kubernetes Node加入集群
- 部署 CNI 网络插件
- 测试 kubernetes 集群
- 停止服务并删除原来的配置
- 二进制搭建(单master集群)
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- 初始化操作
- 部署etcd集群
- 安装Docker
- 部署master节点
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- 解压二进制包
- 部署kube-apiserver
- 部署kube-controller-manager
- 部署 kube-scheduler
- 部署master node节点
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- 部署kubelet
- 部署kube-proxy
- 部署网络组件(Calico)
- 授权apiserver访问kubelet
- 新增加work node
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- 删除kubelet证书和kubeconfig文件
- 修改主机名
- 启动并设置开机自启
- 在Master上同意新的Node kubelet证书申请
- 部署Dashboard和CoreDNS
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- 部署CoreDNS
- 从节点使用kubectl
- 清空k8s环境
搭建kubernetes集群
kubeadm
初始化操作
# 1 关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
# 2 关闭iptables服务
[root@master ~]# systemctl stop iptables
[root@master ~]# systemctl disable iptables
# 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
# 关闭完swap后，一定要重启一下虚拟机！！！
# 根据规划设置主机名
hostnamectl set-hostname
# 在master添加hosts
cat >> /etc/hosts << EOF
172.26.22.200 master
172.26.22.201 salve
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 -y
ntpdate time.windows.com
安装软件(master、所有node节点)
安装docker，注意版本
# 1、切换镜像源
[root@master ~]# wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
# 2、查看当前镜像源中支持的docker版本
[root@master ~]# yum list docker-ce --showduplicates
# 3、安装特定版本的docker-ce
# 必须制定--setopt=obsoletes=0，否则yum会自动安装更高版本
[root@master ~]# yum install --setopt=obsoletes=0 docker-ce-18.06.3.ce-3.el7 -y
# 4、添加一个配置文件
#Docker 在默认情况下使用Vgroup Driver为cgroupfs，而Kubernetes推荐使用systemd来替代cgroupfs
[root@master ~]# mkdir /etc/docker
[root@master ~]# cat < /etc/docker/daemon.json
{
"exec-opts": ["native.cgroupdriver=systemd"],
"registry-mirrors": ["https://kn0t2bca.mirror.aliyuncs.com"]
}
EOF
# 5、启动dokcer
[root@master ~]# systemctl restart docker
[root@master ~]# systemctl enable docker
修改源
cat > /etc/yum.repos.d/kubernetes.repo << EOF
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
安装 kubeadm、kubelet、kubectl
yum install -y kubelet-1.23.6 kubeadm-1.23.6 kubectl-1.23.6
systemctl enable kubelet
# 配置关闭 Docker 的 cgroups，修改 /etc/docker/daemon.json，加入以下内容
{"exec-opts": ["native.cgroupdriver=systemd"]}
# 重启 docker
systemctl daemon-reload
systemctl restart docker
Kubernetes Master初始化
# 在 Master 节点下执行
kubeadm init \
--apiserver-advertise-address=172.26.22.200 \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version v1.23.6 \
--service-cidr=10.96.0.0/12 \
--pod-network-cidr=10.244.0.0/16
"""
Your Kubernetes control-plane has initialized successfully!
To start using your cluster, you need to run the following as a regular user:
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
Alternatively, if you are the root user, you can run:
export KUBECONFIG=/etc/kubernetes/admin.conf
You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
https://kubernetes.io/docs/concepts/cluster-administration/addons/
Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 172.26.22.200:6443 --token to99q6.h0nbbv93hwovz6el \
--discovery-token-ca-cert-hash sha256:3a63cffd591cbb9b0842cd39169fddae83099359664a09e09cc8aa91b671e121
"""
# 安装成功后，复制如下配置并执行
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
kubectl get nodes
Kubernetes Node加入集群
分别在 k8s-node1 和 k8s-node2 执行
# 下方命令可以在 k8s master 控制台初始化成功后复制 join 命令
kubeadm join 192.168.113.120:6443 --token w34ha2.66if2c8nwmeat9o7 --discovery-token-ca-cert-hash sha256:20e2227554f8883811c01edd850f0cf2f396589d32b57b9984de3353a7389477
# 如果初始化的 token 不小心清空了，可以通过如下命令获取或者重新申请
# 如果 token 已经过期，就重新申请
kubeadm token create
# token 没有过期可以通过如下命令获取
kubeadm token list
# 获取 --discovery-token-ca-cert-hash 值，得到值后需要在前面拼接上 sha256:
openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | \
openssl dgst -sha256 -hex | sed 's/^.* //'
部署 CNI 网络插件
# 在 master 节点上执行
# 下载 calico 配置文件，可能会网络超时
# curl https://raw.githubusercontent.com/projectcalico/calico/v3.26.1/manifests/calico.yaml -O
curl -O https://docs.tigera.io/archive/v3.25/manifests/calico.yaml
# kubectl apply –f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
# 修改 calico.yaml 文件中的 CALICO_IPV4POOL_CIDR 配置，修改为与初始化的 cidr 相同
10.244.0.0/16
# 修改 IP_AUTODETECTION_METHOD 下的网卡名称
# 删除镜像 docker.io/ 前缀，避免下载过慢导致失败
sed -i 's#docker.io/##g' calico.yaml
# 部署
kubectl apply -f calico.yaml
# 查看是否正常
kubectl get cs
测试 kubernetes 集群
# 创建部署
kubectl create deployment nginx --image=nginx
# 暴露端口
kubectl expose deployment nginx --port=80 --type=NodePort
# 查看 pod 以及服务信息
kubectl get pod,svc
停止服务并删除原来的配置
kubeadm reset -f
rm -rf ~/.kube/
rm -rf /etc/kubernetes/
rm -rf /etc/systemd/system/kubelet.service.d
rm -rf /etc/systemd/system/kubelet.service
rm -rf /usr/bin/kube*
http://unifygateway.htsec.com/search_ehtc/csearch/ehtc_app?app_name=ehtc_app&appid=199608&page=1&per_page=5&query=海通&scene=all&sign_value=9ca66afd2c1c98aea79ec2c63f320789×tamp=169208289
二进制搭建(单master集群)
初始化操作
# 1 关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
# 2 关闭iptables服务
[root@master ~]# systemctl stop iptables
[root@master ~]# systemctl disable iptables
# 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
# 关闭完swap后，一定要重启一下虚拟机！！！
# 根据规划设置主机名
hostnamectl set-hostname
# 在master添加hosts
cat >> /etc/hosts << EOF
172.26.22.200 master
172.26.22.201 salve
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 -y
ntpdate time.windows.com
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。
注：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。
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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。
# 找任意一台服务器操作，这里用 Master 节点。 wget https://pkg.cfssl.org/R1.2/cfssl_linux-amd64 wget https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64 wget https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64 chmod +x cfssl_linux-amd64 cfssljson_linux-amd64 cfssl-certinfo_linux-amd64 mv cfssl_linux-amd64 /usr/local/bin/cfssl mv cfssljson_linux-amd64 /usr/local/bin/cfssljson mv cfssl-certinfo_linux-amd64 /usr/bin/cfssl-certinfo -
生成 Etcd 证书
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自签证书颁发机构（CA）
# 创建工作目录 mkdir -p ~/TLS/{etcd,k8s} cd TLS/etcd# 自签CA证书 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 - ls *pem ca-key.pem ca.pem -
使用自签 CA 签发 Etcd HTTPS 证书
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。
# 创建证书申请文件 cat > server-csr.json << EOF { "CN": "etcd", "hosts": [ "172.26.22.200", "172.26.22.201" ], "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "L": "BeiJing", "ST": "BeiJing" } ] } EOF# 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 ls server*pem server-key.pem server.pem
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从github上下载二进制文件
#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 -
部署etcd集群
涉及到的服务器都要如下操作
# 创建工作目录并解压二进制包 mkdir /opt/etcd/{bin,cfg,ssl} –p tar zxvf etcd-v3.4.9-linux-amd64.tar.gz mv etcd-v3.4.9-linux-amd64/{etcd,etcdctl} /opt/etcd/bin/# 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://172.26.22.200:2380" ETCD_LISTEN_CLIENT_URLS="https://172.26.22.200:2379" #[Clustering] ETCD_INITIAL_ADVERTISE_PEER_URLS="https://172.26.22.200:2380" ETCD_ADVERTISE_CLIENT_URLS="https://172.26.22.200:2379" ETCD_INITIAL_CLUSTER="etcd-1=https://172.26.22.200:2380,etcd-2=https://172.26.22.201:2380" 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
# systemd 管理 etcd cat > /usr/lib/systemd/system/etcd.service << EOF [Unit] Description=Etcd Server After=network.target After=network-online.target Wants=network-online.target [Service] Type=notify EnvironmentFile=/opt/etcd/cfg/etcd.conf ExecStart=/opt/etcd/bin/etcd \ --cert-file=/opt/etcd/ssl/server.pem \ --key-file=/opt/etcd/ssl/server-key.pem \ --peer-cert-file=/opt/etcd/ssl/server.pem \ --peer-key-file=/opt/etcd/ssl/server-key.pem \ --trusted-ca-file=/opt/etcd/ssl/ca.pem \ --peer-trusted-ca-file=/opt/etcd/ssl/ca.pem \ --logger=zap Restart=on-failure LimitNOFILE=65536 [Install] WantedBy=multi-user.target EOF# 拷贝刚才生成的证书 cp ~/TLS/etcd/ca*pem ~/TLS/etcd/server*pem /opt/etcd/ssl/# 将上面节点 1 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/ [email protected]$i:/opt/ scp /usr/lib/systemd/system/etcd.service [email protected]$i:/usr/lib/systemd/system/ done # 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"# 启动并设置开机启动 # 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# 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 | | +-----------------------------+--------+-------------+-------+# etcd问题排查 less /var/log/message journalctl -u etcd
安装Docker
k8s在1.20版本就不在支持docker，在1.24版本移除了docker
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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/ -
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 -
启动并设置开机自启动
systemctl daemon-reload systemctl start docker systemctl enable docker
部署master节点
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生成kube-apiserver证书
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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 - ls *pem ca-key.pem ca.pem -
使用自签CA签发kube-apiserver https证书
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。
# 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
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下载
下载地址：https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.23.md
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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/ -
部署kube-apiserver
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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
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拷贝刚才生成的证书
cp ~/TLS/k8s/ca*pem ~/TLS/k8s/server*pem /opt/kubernetes/ssl/ -
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 bootstrapping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 ' ' ```
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systemd管理apiserve
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 -
启动并设置开机启动
systemctl daemon-reload systemctl start kube-apiserver systemctl enable kube-apiserver
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部署kube-controller-manager
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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
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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} -
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 -
启动并设置开机自启
systemctl daemon-reload systemctl start kube-controller-manager systemctl enable kube-controller-manager
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部署 kube-scheduler
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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)。
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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=${KUBE_CONFIG} -
systemd管理scheduler
cat > /usr/lib/systemd/system/kube-scheduler.service << EOF [Unit] Description=Kubernetes Scheduler Documentation=https://github.com/kubernetes/kubernetes [Service] EnvironmentFile=/opt/kubernetes/cfg/kube-scheduler.conf ExecStart=/opt/kubernetes/bin/kube-scheduler \$KUBE_SCHEDULER_OPTS Restart=on-failure [Install] WantedBy=multi-user.target EOF -
启动并设置开机启动
systemctl daemon-reload systemctl start kube-scheduler systemctl enable kube-scheduler -
查看集群状态
生成kubectl连接集群的证书 ：
cat > admin-csr.json <生成kubeconfig文件 ：
mkdir /root/.kube KUBE_CONFIG="/root/.kube/config" KUBE_APISERVER="https://192.168.242.51:6443" kubectl config set-cluster kubernetes \ --certificate-authority=/opt/kubernetes/ssl/ca.pem \ --embed-certs=true \ --server=${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。 -
授权kubelet-bootstrap用户允许请求证书
kubectl create clusterrolebinding kubelet-bootstrap \ --clusterrole=system:node-bootstrapper \ --user=kubelet-bootstrap
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部署master node节点
下面还是在master node上面操作,即当Master节点,也当Work Node节点
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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 [email protected]$i:/opt/kubernetes/bin/ done -
部署kubelet
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创建配置文件
cat > /opt/kubernetes/cfg/kubelet.conf << EOF KUBELET_OPTS="--logtostderr=false \\ --v=2 \\ --log-dir=/opt/kubernetes/logs \\ --hostname-override=k8s-master1 \\ --network-plugin=cni \\ --kubeconfig=/opt/kubernetes/cfg/kubelet.kubeconfig \\ --bootstrap-kubeconfig=/opt/kubernetes/cfg/bootstrap.kubeconfig \\ --config=/opt/kubernetes/cfg/kubelet-config.yml \\ --cert-dir=/opt/kubernetes/ssl \\ --pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0" EOF- –hostname-override ：显示名称,集群唯一(不可重复)。
- –network-plugin ：启用CNI。
- –kubeconfig ： 空路径,会自动生成,后面用于连接apiserver。
- –bootstrap-kubeconfig ：首次启动向apiserver申请证书。
- –config ：配置文件参数。
- –cert-dir ：kubelet证书目录。
- –pod-infra-container-image ：管理Pod网络容器的镜像 init container
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配置文件
cat > /opt/kubernetes/cfg/kubelet-config.yml << EOF kind: KubeletConfiguration apiVersion: kubelet.config.k8s.io/v1beta1 address: 0.0.0.0 port: 10250 readOnlyPort: 10255 cgroupDriver: cgroupfs clusterDNS: - 10.0.0.2 clusterDomain: cluster.local failSwapOn: false authentication: anonymous: enabled: false webhook: cacheTTL: 2m0s enabled: true x509: clientCAFile: /opt/kubernetes/ssl/ca.pem authorization: mode: Webhook webhook: cacheAuthorizedTTL: 5m0s cacheUnauthorizedTTL: 30s evictionHard: imagefs.available: 15% memory.available: 100Mi nodefs.available: 10% nodefs.inodesFree: 5% maxOpenFiles: 1000000 maxPods: 110 EOF -
生成kubelet初次加入集群引导kubeconfig文件
KUBE_CONFIG="/opt/kubernetes/cfg/bootstrap.kubeconfig" KUBE_APISERVER="https://192.168.242.51:6443" # apiserver IP:PORT TOKEN="4136692876ad4b01bb9dd0988480ebba" # 与token.csv里保持一致 /opt/kubernetes/cfg/token.csv # 生成 kubelet bootstrap kubeconfig 配置文件 kubectl config set-cluster kubernetes \ --certificate-authority=/opt/kubernetes/ssl/ca.pem \ --embed-certs=true \ --server=${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} -
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 -
启动并设置开机启动
systemctl daemon-reload systemctl start kubelet systemctl enable kubelet -
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 NotReady2m11s v1.20.10 由于网络插件还没有部署,节点会没有准备就绪NotReady
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部署kube-proxy
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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 -
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 -
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 -
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} -
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 -
启动并设置开机自启
systemctl daemon-reload systemctl start kube-proxy systemctl enable kube-proxy
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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 Ready21m v1.20.10 -
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
新增加work node
所有node节点可以参考如下
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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 [email protected]$i:/opt/; done for i in {2..3}; do scp -r /usr/lib/systemd/system/{kubelet,kube-proxy}.service [email protected]$i:/usr/lib/systemd/system; done for i in {2..3}; do scp -r /opt/kubernetes/ssl/ca.pem [email protected]$i:/opt/kubernetes/ssl/; done -
删除kubelet证书和kubeconfig文件
rm -f /opt/kubernetes/cfg/kubelet.kubeconfig rm -f /opt/kubernetes/ssl/kubelet* 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 -
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 -
启动并设置开机自启
systemctl daemon-reload systemctl start kubelet kube-proxy systemctl enable kubelet kube-proxy -
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 -
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 Ready46h v1.20.10 k8s-node1 Ready 77s v1.20.10
部署Dashboard和CoreDNS
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部署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 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 10.0.0.2068000/TCP 10m service/kubernetes-dashboard NodePort 10.0.0.10 443:30001/TCP 10m 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)
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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
从节点使用kubectl
# 1. 将 master 节点中 /etc/kubernetes/admin.conf 拷贝到需要运行的服务器的 /etc/kubernetes 目录中
scp /etc/kubernetes/admin.conf root@k8s-node1:/etc/kubernetes
# 2. 在对应的服务器上配置环境变量
echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.bash_profile
source ~/.bash_profile
清空k8s环境
#!/bin/bash
kubeadm reset -f
modprobe -r ipip
lsmod
rm -rf ~/.kube/
rm -rf /etc/kubernetes/
rm -rf /etc/systemd/system/kubelet.service.d
rm -rf /etc/systemd/system/kubelet.service
rm -rf /usr/bin/kube*
rm -rf /etc/cni
rm -rf /opt/cni
rm -rf /var/lib/etcd
rm -rf /var/etcd
yum -y remove kubeadm* kubectl* kubelet* docker*
reboot