tags:
categories:
适合人群: 软件工程师 测试工程师 运维工程师 软件架构师项目经理
服务分类
- 有状态服务: DBMS (数据库管理系统)
- 无状态服务: LVS APACHE docker更适用于它，但是K8s的目标是有状态服务
主要组件
部分重要插件
3. 同一个Pod内部通讯:同- 一个Pod共享同一个网络命名空间，共享同一个Linux 协议栈
4. Pod1至Pod2
IPADDR=192.168.66.10
NETMASK=255.255.255.0
GATEWAY=192.168.66.133
DNS1=192.168.66.1
DNS2=114.114.114.114
# 设置主机名
hostnamectl set-hostname k8s-master
# 让每台机子可以相互解析 在添加
vi /etc/hosts
192.168.66.10 k8s-master
192.168.66.20 k8s-node1
192.168.66.21 k8s-node2
192.168.66.100 hub.qnhyn.com
# hosts复制到别的虚拟机
scp /etc/hosts root@k8s-node2:/etc/hosts
# 安装依赖包
yum install -y conntrack ntpdate ntp ipvsadm ipset jq iptables curl sysstat libseccomp wget vim net-tools git
# 关闭防火墙
swapoff -a && sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab
setenforce 0 && sed -i 's/^SELINUX=.*/SELINUX=disabled/' /etc/selinux/config
# 调整内核参数，对于K8S
cat > /etc/sysctl.d/kubernetes.conf << EOF
net.bridge.bridge-nf-call-iptables=1
net.bridge.bridge-nf-call-ip6tables=1
net.ipv4.ip_forward=1
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.tcp_tw_recycle=0
vm.swappiness=0 # 禁止使用 swap 空间，只有当系统 OOM 时才允许使用它
vm.overcommit_memory=1 # 不检查物理内存是否够用
vm.panic_on_oom=0 # 开启 OOM
fs.inotify.max_user_instances=8192
fs.inotify.max_user_watches=1048576
fs.file-max=52706963
fs.nr_open=52706963
net.ipv6.conf.all.disable_ipv6=1
net.netfilter.nf_conntrack_max=2310720
EOF
sysctl -p /etc/sysctl.d/kubernetes.conf
# 调整系统时区
#设置系统时区为 中国/上海
timedatectl set-timezone Asia/Shanghai
#将当前的 UTC 时间写入硬件时钟
timedatectl set-local-rtc 0
#重启依赖于系统时间的服务
systemctl restart rsyslog
systemctl restart crond
# 关闭不需要的服务
systemctl stop postfix && systemctl disable postfix
# 设置 rsyslogd 和 systemd journald
#创建持久化保存日志的目录
mkdir /var/log/journal
mkdir /etc/systemd/journald.conf.d
cat > /etc/systemd/journald.conf.d/99-prophet.conf <<EOF
[Journal]
#持久化保存到磁盘
Storage=persistent
#压缩历史日志
Compress=yes
SyncIntervalSec=5m
RateLimitInterval=30s
RateLimitBurst=1000
#最大占用空间 10G
SystemMaxUse=10G
#单日志文件最大 200M
SystemMaxFileSize=200M
#日志保存时间 2 周
MaxRetentionSec=2week
#不将日志转发到 syslog
ForwardToSyslog=no
EOF
systemctl restart systemd-journald
# 升级系统内核为 4.44（可选）
# CentOS 7.x 系统自带的 3.10.x 内核存在一些 Bugs，导致运行的 Docker、Kubernetes 不稳定，查看内核命令uname -r，升级步骤如下：
rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm
#安装完成后检查 /boot/grub2/grub.cfg 中对应内核 menuentry 中是否包含 initrd16 配置，如果没有，再安装一次!
yum --enablerepo=elrepo-kernel install -y kernel-lt
#设置开机从新内核启动
grub2-set-default "CentOS Linux (4.4.182-1.el7.elrepo.x86_64) 7 (Core)"
# 重启后产看内核变化啦
reboot
uname -r
sudo setenforce 0
sed -i "s/SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config
# 关闭防火墙和ipttables 如果不设置后面加入节点可能有问题如:couldn't validate the identity of the API Server
cat <<EOF > /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward=1
EOF
sudo sysctl --system
sudo systemctl stop firewalld
sudo systemctl disable firewalld
sudo swapoff -a
yes | cp /etc/fstab /etc/fstab_bak
cat /etc/fstab_bak |grep -v swap > /etc/fstab
# 由于ipvs已经加入到了内核的主干，所以为kube-proxy开启ipvs的前提需要加载以下的内核模块
modprobe br_netfilter
cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
EOF
chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep -e ip_vs -e nf_conntrack_ipv4
# 脚本创建了的/etc/sysconfig/modules/ipvs.modules文件, 保证在节点重启后能自动加载所需模块。 使用lsmod | grep -e ip_vs -e nf_conntrack_ipv4命令查看是否已经正确加载所需的内核模块。
# 安装依赖库
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
# 导入阿里云的镜像仓库
sudo yum-config-manager \
--add-repo \
http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
# 下载安装docker
yum update -y && yum install -y docker-ce
# 创建/etc/docker目录
mkdir /etc/docker
# 设置一下daemon中cgroup为syetemd 默认有两个cgroup 存储文件格式为json-flle,大小为100Mb
cat > /etc/docker/daemon.json <<EOF
{
"exec-opts": ["native.cgroupdriver=systemd"],
"log-driver": "json-file",
"log-opts": {
"max-size": "100m"
}
}
EOF
# 创建目录存放docker配置文件
mkdir -p /etc/systemd/system/docker.service.d
#重启docker服务
systemctl daemon-reload && systemctl restart docker && systemctl enable docker
# 配置K8S的yum源
cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
# 安装kubeadm, kubectl, and kubelet.
sudo yum install -y kubelet-1.18.0 kubeadm-1.18.0 kubectl-1.18.0
sudo systemctl restart kubelet
sudo systemctl enable kubelet
# 生成默认初始化模板
kubeadm config print init-defaults > kubeadm-config.yaml
# 修改默认初始化模板
advertiseAddress: 192.168.66.10 # 修改ip地址
kubernetesVersion: v1.18.0 # 修改版本
# 加上podSubnet(不要忘记啦),如果忘记了 后期安装网络后需要到配置文件中修改。
networking:
dnsDomain: cluster.local
podSubnet: 10.244.0.0/16
serviceSubnet: 10.96.0.0/12
# 添加字段 修改ipvs调度方式
---
apiVersion: kubeproxy.config.k8s.io/v1alpha1
kind: KubeProxyConfiguration
featureGates:
SupportIPVSProxyMode: true
mode: ipvs
# 先拉取所需要的镜像 运行脚本如下 镜像到了阿里云的杭州机房的容器仓库里，拉取还是比较快的
echo ""
echo "=========================================================="
echo "Pull Kubernetes v1.18.0 Images from aliyuncs.com ......"
echo "=========================================================="
echo ""
MY_REGISTRY=registry.cn-hangzhou.aliyuncs.com/openthings
## 拉取镜像
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-apiserver:v1.18.0
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-controller-manager:v1.18.0
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-scheduler:v1.18.0
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-proxy:v1.18.0
docker pull ${MY_REGISTRY}/k8s-gcr-io-etcd:3.4.3-0
docker pull ${MY_REGISTRY}/k8s-gcr-io-pause:3.2
docker pull ${MY_REGISTRY}/k8s-gcr-io-coredns:1.6.7
## 添加Tag
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-apiserver:v1.18.0 k8s.gcr.io/kube-apiserver:v1.18.0
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-scheduler:v1.18.0 k8s.gcr.io/kube-scheduler:v1.18.0
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-controller-manager:v1.18.0 k8s.gcr.io/kube-controller-manager:v1.18.0
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-proxy:v1.18.0 k8s.gcr.io/kube-proxy:v1.18.0
docker tag ${MY_REGISTRY}/k8s-gcr-io-etcd:3.4.3-0 k8s.gcr.io/etcd:3.4.3-0
docker tag ${MY_REGISTRY}/k8s-gcr-io-pause:3.2 k8s.gcr.io/pause:3.2
docker tag ${MY_REGISTRY}/k8s-gcr-io-coredns:1.6.7 k8s.gcr.io/coredns:1.6.7
echo ""
echo "=========================================================="
echo "Pull Kubernetes v1.18.0 Images FINISHED."
echo "into registry.cn-hangzhou.aliyuncs.com/openthings, "
echo " by openthings@https://my.oschina.net/u/2306127."
echo "=========================================================="
echo ""
# 根据模板初始化节点
kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.log
# 配置一下
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
# 安装fannel网络插件
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
# 如果拉取镜像失败
# https://github.com/coreos/flannel/releases 方仓库下载镜像下载flanneld-v0.12.0-arm64.docker
docker load < flanneld-v0.12.0-arm64.docker
sudo systemctl restart kubelet
kubectl get nodes
kubectl get pod --all-namespaces
# 添加从节点
scp ~/flanneld-v0.12.0-arm64.docker root@k8s-node1:~/
scp ~/flanneld-v0.12.0-arm64.docker root@k8s-node2:~/
docker load < flanneld-v0.12.0-arm64.docker
kubeadm join 192.168.66.10:6443 --token abcdef.0123456789abcdef \
--discovery-token-ca-cert-hash sha256:6e09e93318ce8126e04eb924a1c0043719614ac07e6e2203c44a6bdcdd86f4b4
docker pull registry.cn-hangzhou.aliyuncs.com/chentging/flannel/flannel:v0.12.0-amd64
# 为镜像打tag，保持和yaml文件一样。
docker tag registry.cn-hangzhou.aliyuncs.com/chentging/flannel/flannel:v0.12.0-amd64 quay.io/coreos/flannel:v0.12.0-amd64
2. 成功构建集群环境。
# 四台机器都加上
cat > /etc/docker/daemon.json <<EOF
{
"exec-opts": ["native.cgroupdriver=systemd"],
"log-driver": "json-file",
"log-opts": {
"max-size": "100m"
},
"insecure-registries": ["https://hub.qnhyn.com"]
}
EOF
# 重启docker
systemctl restart docker
systemctl restart kubelet
curl -L https://get.daocloud.io/docker/compose/releases/download/1.25.4/docker-compose-`uname -s`-`uname -m` > /usr/local/bin/docker-compose
chmod +x /usr/local/bin/docker-compose
ln -s /usr/local/bin/docker-compose /usr/bin/docker-compose
docker-compose --version
# 用来拉取文件到xshell中
yum -y install lrzsz
# 解压
tar -zxvf harbor-offline-installer-v1.10.1.tgz
# 创建证书目录，并赋予权限
mkdir -p /data/cert && chmod -R 777 /data/cert && cd /data/cert
# 生成私钥，需要设置密码 两次密码输入保持一致
openssl genrsa -des3 -out harbor.key 2048
# 生成CA证书，需要输入密码
openssl req -sha512 -new \
-subj "/C=CN/ST=JS/L=WX/O=zwx/OU=qnhyn/CN=hub.qnhyn.com" \
-key harbor.key \
-out harbor.csr
# 备份证书
cp harbor.key harbor.key.org
# 退掉私钥密码，以便docker访问（也可以参考官方进行双向认证）
openssl rsa -in harbor.key.org -out harbor.key
# 使用证书进行签名
openssl x509 -req -days 365 -in harbor.csr -signkey harbor.key -out harbor.crt
# 修改配置文件 下面字段
hostname: hub.qnhyn.com
certificate: /data/cert/harbor.crt
private_key: /data/cert/harbor.key
harbor_admin_password: Harbor12345
#安装
./install.sh --with-clair
# 物理机上配置hosts 192.168.66.100 hub.qnhyn.com
https://hub.qnhyn.com/ # 账号admin # 密码 Harbor12345
# k8s任意一节点上 用户名admin 密码Harbor12345
docker login https://hub.qnhyn.com
# 推送镜像前必须先标记镜像
docker tag quay.io/coreos/flannel:v0.12.0-amd64 hub.qnhyn.com/library/quay.io/coreos/flannel:v0.12.0-amd64
# 推送镜像
docker push hub.qnhyn.com/library/quay.io/coreos/flannel:v0.12.0-amd64
# 测试myapp
docker pull registry.cn-hangzhou.aliyuncs.com/k8s-t/wangyanglinux:v1
docker tag registry.cn-hangzhou.aliyuncs.com/k8s-t/wangyanglinux:v1 myapp
kubectl run nginx-deployment --image=hub.qnhyn.com/library/myapp --port=80
# 通过详细信息查看ip 10.244.2.4
kubectl get pod -o wide
# 查看部署
kubectl get deployment
# 访问容器
curl 10.244.2.4
curl 10.244.2.4
curl 10.244.2.4/hostname.html
# 进行扩容
kubectl scale -- replicas=3 deployment/nginx-deployment
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
# 创建2个nginx容器
replicas: 2
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:latest
ports:
- containerPort: 80