集群方案：
- 发行版：CentOS 7
- 容器运行时
- 内核： 4.18.12-1.el7.elrepo.x86_64
- 版本：Kubernetes: 1.14.0
- 网络方案: Calico
- kube-proxy mode: IPVS
- master高可用方案：HAProxy keepalived LVS
- DNS插件: CoreDNS
- metrics插件：metrics-server
- 界面：kubernetes-dashboard
Kubernetes集群搭建
| Host Name | Role | IP |
|---|---|---|
| master1 | master1 | 192.168.56.103 |
| master2 | master2 | 192.168.56.104 |
| master3 | master3 | 192.168.56.105 |
| node1 | node1 | 192.168.56.106 |
| node2 | node2 | 192.168.56.107 |
| node3 | node3 | 192.168.56.108 |
1、离线安装包准备（基于能够访问外网的服务器下载相应安装包）
# 设置yum缓存路径，cachedir 缓存路径 keepcache=1保持安装包在软件安装之后不删除
cat /etc/yum.conf
[main]
cachedir=/home/yum
keepcache=1
...
# 安装ifconfig
yum install net-tools -y
# 时间同步
yum install -y ntpdate
# 安装docker（建议19.8.06）
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager \
--add-repo \
https://download.docker.com/linux/centos/docker-ce.repo
yum makecache fast
## 列出Docker版本
yum list docker-ce --showduplicates | sort -r
## 安装指定版本
sudo yum install docker-ce-<VERSION_STRING>
# 安装文件管理器，XShell可通过rz sz命令上传或者下载服务器文件
yum intall lrzsz -y
# 安装keepalived、haproxy
yum install -y socat keepalived ipvsadm haproxy
# 安装kubernetes相关组件
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
yum install -y kubelet kubeadm kubectl ebtables
# 其他软件安装
yum install wget
...
2、节点系统配置
-
关闭SELinux、防火墙
systemctl stop firewalld systemctl disable firewalld setenforce 0 sed -i "s/SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config -
关闭系统的Swap（Kubernetes 1.8开始要求）
swapoff -a yes | cp /etc/fstab /etc/fstab_bak cat /etc/fstab_bak |grep -v swap > /etc/fstab -
配置L2网桥在转发包时会被iptables的FORWARD规则所过滤，该配置被CNI插件需要，更多信息请参考Network Plugin Requirements
echo """ vm.swappiness = 0 net.bridge.bridge-nf-call-ip6tables = 1 net.bridge.bridge-nf-call-iptables = 1 """ > /etc/sysctl.conf sysctl -pcentos7添加bridge-nf-call-ip6tables出现No such file or directory,简单来说就是执行一下 modprobe br_netfilter
-
同步时间
ntpdate -u ntp.api.bz -
升级内核到最新（已准备内核离线安装包，可选）
grub2-set-default 0 && grub2-mkconfig -o /etc/grub2.cfg grubby --default-kernel grubby --args="user_namespace.enable=1" --update-kernel="$(grubby --default-kernel)" -
重启系统，确认内核版本后，开启IPVS（如果未升级内核，去掉ip_vs_fo）
uname -a cat > /etc/sysconfig/modules/ipvs.modules <<EOF #!/bin/bash ipvs_modules="ip_vs ip_vs_lc ip_vs_wlc ip_vs_rr ip_vs_wrr ip_vs_lblc ip_vs_lblcr ip_vs_dh ip_vs_sh ip_vs_fo ip_vs_nq ip_vs_sed ip_vs_ftp nf_conntrack" for kernel_module in \${ipvs_modules}; do /sbin/modinfo -F filename \${kernel_module} > /dev/null 2>&1 if [ $? -eq 0 ]; then /sbin/modprobe \${kernel_module} fi done EOF chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep ip_vs执行sysctl -p报错可执行modprobe br_netfilter，请参考centos7添加bridge-nf-call-ip6tables出现No such file or directory
-
所有机器需要设定/etc/sysctl.d/k8s.conf的系统参数
# https://github.com/moby/moby/issues/31208 # ipvsadm -l --timout # 修复ipvs模式下长连接timeout问题 小于900即可 cat <<EOF > /etc/sysctl.d/k8s.conf net.ipv4.tcp_keepalive_time = 600 net.ipv4.tcp_keepalive_intvl = 30 net.ipv4.tcp_keepalive_probes = 10 net.ipv6.conf.all.disable_ipv6 = 1 net.ipv6.conf.default.disable_ipv6 = 1 net.ipv6.conf.lo.disable_ipv6 = 1 net.ipv4.neigh.default.gc_stale_time = 120 net.ipv4.conf.all.rp_filter = 0 net.ipv4.conf.default.rp_filter = 0 net.ipv4.conf.default.arp_announce = 2 net.ipv4.conf.lo.arp_announce = 2 net.ipv4.conf.all.arp_announce = 2 net.ipv4.ip_forward = 1 net.ipv4.tcp_max_tw_buckets = 5000 net.ipv4.tcp_syncookies = 1 net.ipv4.tcp_max_syn_backlog = 1024 net.ipv4.tcp_synack_retries = 2 net.bridge.bridge-nf-call-ip6tables = 1 net.bridge.bridge-nf-call-iptables = 1 net.netfilter.nf_conntrack_max = 2310720 fs.inotify.max_user_watches=89100 fs.may_detach_mounts = 1 fs.file-max = 52706963 fs.nr_open = 52706963 net.bridge.bridge-nf-call-arptables = 1 vm.swappiness = 0 vm.overcommit_memory=1 vm.panic_on_oom=0 EOF sysctl --system -
设置开机启动
# 启动docker sed -i "13i ExecStartPost=/usr/sbin/iptables -P FORWARD ACCEPT" /usr/lib/systemd/system/docker.service systemctl daemon-reload systemctl enable docker systemctl start docker # 设置kubelet开机启动 systemctl enable kubelet systemctl enable keepalived systemctl enable haproxy -
设置免密登录
# 1、三次回车后，密钥生成完成 ssh-keygen # 2、拷贝密钥到其他节点 ssh-copy-id -i ~/.ssh/id_rsa.pub 用户名字@192.168.x.xxx
**、 Kubernetes要求集群中所有机器具有不同的Mac地址、产品uuid、Hostname。
3、keepalived+haproxy配置
cd ~/
# 创建集群信息文件
echo """
CP0_IP=192.168.56.103
CP1_IP=192.168.56.104
CP2_IP=192.168.56.105
VIP=192.168.56.102
NET_IF=eth0
CIDR=10.244.0.0/16
""" > ./cluster-info
bash -c "$(curl -fsSL https://raw.githubusercontent.com/hnbcao/kubeadm-ha-master/v1.14.0/keepalived-haproxy.sh)"
4、部署HA Master
HA Master的部署过程已经自动化，请在master-1上执行如下命令，并注意修改IP;
脚本主要执行三步：
1)、重置kubelet设置
kubeadm reset -f
rm -rf /etc/kubernetes/pki/
2)、编写节点配置文件并初始化master1的kubelet
echo """
apiVersion: kubeadm.k8s.io/v1beta1
kind: ClusterConfiguration
kubernetesVersion: v1.13.0
controlPlaneEndpoint: "${VIP}:8443"
maxPods: 100
networkPlugin: cni
imageRepository: registry.aliyuncs.com/google_containers
apiServer:
certSANs:
- ${CP0_IP}
- ${CP1_IP}
- ${CP2_IP}
- ${VIP}
networking:
# This CIDR is a Calico default. Substitute or remove for your CNI provider.
podSubnet: ${CIDR}
---
apiVersion: kubeproxy.config.k8s.io/v1alpha1
kind: KubeProxyConfiguration
mode: ipvs
""" > /etc/kubernetes/kubeadm-config.yaml
kubeadm init --config /etc/kubernetes/kubeadm-config.yaml
mkdir -p $HOME/.kube
cp -f /etc/kubernetes/admin.conf ${HOME}/.kube/config
- 关于默认网关问题，如果有多张网卡，需要先将默认网关切换到集群使用的那张网卡上，否则可能会出现etcd无法连接等问题。（应用我用的虚拟机，有一张网卡无法做到各个节点胡同；route查看当前网关信息，route del default删除默认网关，route add default enth0设置默认网关enth0为网卡名）
3)、拷贝相关证书到master2、master3
for index in 1 2; do
ip=${IPS[${index}]}
ssh $ip "mkdir -p /etc/kubernetes/pki/etcd; mkdir -p ~/.kube/"
scp /etc/kubernetes/pki/ca.crt $ip:/etc/kubernetes/pki/ca.crt
scp /etc/kubernetes/pki/ca.key $ip:/etc/kubernetes/pki/ca.key
scp /etc/kubernetes/pki/sa.key $ip:/etc/kubernetes/pki/sa.key
scp /etc/kubernetes/pki/sa.pub $ip:/etc/kubernetes/pki/sa.pub
scp /etc/kubernetes/pki/front-proxy-ca.crt $ip:/etc/kubernetes/pki/front-proxy-ca.crt
scp /etc/kubernetes/pki/front-proxy-ca.key $ip:/etc/kubernetes/pki/front-proxy-ca.key
scp /etc/kubernetes/pki/etcd/ca.crt $ip:/etc/kubernetes/pki/etcd/ca.crt
scp /etc/kubernetes/pki/etcd/ca.key $ip:/etc/kubernetes/pki/etcd/ca.key
scp /etc/kubernetes/admin.conf $ip:/etc/kubernetes/admin.conf
scp /etc/kubernetes/admin.conf $ip:~/.kube/config
ssh ${ip} "${JOIN_CMD} --experimental-control-plane"
done
4)、master2、master3加入节点
JOIN_CMD=`kubeadm token create --print-join-command`
ssh ${ip} "${JOIN_CMD} --experimental-control-plane"
完整脚本：
# 部署HA master
bash -c "$(curl -fsSL https://raw.githubusercontent.com/hnbcao/kubeadm-ha-master/v1.14.0/kube-ha.sh)"
5、加入节点
-
各个节点需要配置keepalived 和 haproxy
#/etc/haproxy/haproxy.cfg global log 127.0.0.1 local2 chroot /var/lib/haproxy pidfile /var/run/haproxy.pid maxconn 4000 user haproxy group haproxy daemon stats socket /var/lib/haproxy/stats defaults mode tcp log global option tcplog option dontlognull option redispatch retries 3 timeout queue 1m timeout connect 10s timeout client 1m timeout server 1m timeout check 10s maxconn 3000 listen stats mode http bind :10086 stats enable stats uri /admin?stats stats auth admin:admin stats admin if TRUE frontend k8s_https *:8443 mode tcp maxconn 2000 default_backend https_sri backend https_sri balance roundrobin server master1-api ${MASTER1_IP}:6443 check inter 10000 fall 2 rise 2 weight 1 server master2-api ${MASTER2_IP}:6443 check inter 10000 fall 2 rise 2 weight 1 server master3-api ${MASTER3_IP}:6443 check inter 10000 fall 2 rise 2 weight 1#/etc/keepalived/keepalived.conf global_defs { router_id LVS_DEVEL } vrrp_script check_haproxy { script /etc/keepalived/check_haproxy.sh interval 3 } vrrp_instance VI_1 { state MASTER interface eth0 virtual_router_id 80 priority 100 advert_int 1 authentication { auth_type PASS auth_pass just0kk } virtual_ipaddress { ${VIP}/24 } track_script { check_haproxy } } }
注意两个配置中的{MASTER2 _ IP},
{VIP}需要替换为自己集群相应的IP地址
-
重启keepalived和haproxy
systemctl stop keepalived systemctl enable keepalived systemctl start keepalived systemctl stop haproxy systemctl enable haproxy systemctl start haproxy -
节点加入命令获取
#master节点执行该命令，再在节点执行获取到的命令 kubeadm token create --print-join-command
6、结束安装
当前集群安装完毕，还需要安装cni插件，推荐使用calico，性能优于其他。
