Kubernetes高可用集群二进制部署(Runtime Docker)
Kubernetes(简称为:k8s)是Google在2014年6月开源的一个容器集群管理系统,使用Go语言开发,用于管理云平台中多个主机上的容器化的应用,Kubernetes的目标是让部署容器化的应用简单并且高效,Kubernetes提供了资源调度、部署管理、服务发现、扩容缩容、监控,维护等一整套功能,努力成为跨主机集群的自动部署、扩展以及运行应用程序容器的平台。 它支持一系列容器工具, 包括Docker、Containerd等。
一、集群环境准备
1.1 主机规划
主机IP地址 | 主机名 | 主机配置 | 主机角色 | 软件列表 |
---|---|---|---|---|
192.168.71.101 | k8s-master1 | 2C4G | master | kube-apiserver、kube-controller-manager、kube-scheduler、etcd、kubelet、kube-proxy、docker-ce |
192.168.71.102 | k8s-worker1 | 2C4G | worker | kubelet、kube-proxy、docker-ce |
192.168.71.103 | k8s-worker1 | 2C4G | worker | kubelet、kube-proxy、docker-ce |
192.168.71.104 | ha1 | 1C2G | LB | haproxy、keepalived |
192.168.71.100 | / | / | VIP(虚拟IP) |
1.2 软件版本
软件名称 | 版本 | 备注 |
---|---|---|
CentOS7 | kernel版本:5.16 | |
kubernetes | v1.21.10 | |
etcd | v3.5.2 | 最新版本 |
calico | v3.19.4 | |
coredns | v1.8.4 | |
docker-ce | 20.10.13 | YUM源默认 |
haproxy | 5.18 | YUM源默认 |
keepalived | 3.5 | YUM源默认 |
1.3 网络分配
网络名称 | 网段 | 备注 |
---|---|---|
Node网络 | 192.168.71.0/24 | |
Service网络 | 10.96.0.0/16 | |
Pod网络 | 10.244.0.0/16 |
二、集群部署
2.1主机准备
2.1.1 主机名设置
hostnamectl --static set-hostname xxx
2.1.2 主机与IP地址解析
cat >> /etc/hosts << EOF
192.168.71.104 ha
192.168.71.101 k8s-master
192.168.71.102 k8s-worker1
192.168.71.103 k8s-worker2
EOF
2.1.3 主机安全设置
2.1.3.1 关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
firewall-cmd --state
2.1.3.2 关闭selinux
setenforce 0
sed -ri 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config
sestatus
2.1.4 交换分区设置
swapoff -a
sed -ri 's/.*swap.*/#&/' /etc/fstab
echo "vm.swappiness=0" >> /etc/sysctl.conf
sysctl -p
2.1.5 主机系统时间同步
安装软件
yum -y install ntpdate
制定时间同步计划任务
crontab -e
0 */1 * * * ntpdate time1.aliyun.com
2.1.6 主机系统优化
limit优化
ulimit -SHn 65535
cat <<EOF >> /etc/security/limits.conf
* soft nofile 655360
* hard nofile 131072
* soft nproc 655350
* hard nproc 655350
* soft memlock unlimited
* hard memlock unlimited
EOF
2.1.7 ipvs管理工具安装及模块加载
为集群节点安装,负载均衡节点不用安装
yum -y install ipvsadm ipset sysstat conntrack libseccomp
可以用yum install ipvsadm ipset sysstat conntrack libseccomp --downloadonly --downloaddir=/fw 下载打包转发到服务器
所有节点配置ipvs模块,在内核4.19+版本nf_conntrack_ipv4已经改为nf_conntrack, 4.18以下使用nf_conntrack_ipv4即可:
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack
创建 /etc/modules-load.d/ipvs.conf 并加入以下内容:
cat >/etc/modules-load.d/ipvs.conf <<EOF
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
ip_vs_sh
nf_conntrack
ip_tables
ip_set
xt_set
ipt_set
ipt_rpfilter
ipt_REJECT
ipip
EOF
设置为开机启动
systemctl enable --now systemd-modules-load.service
2.1.8 Linux内核升级
在所有节点中安装,需要重新操作系统更换内核。
[root@localhost ~]# yum -y install perl
可以用yum install perl --downloadonly --downloaddir=/fw 下载打包转发到服务器
[root@localhost ~]# rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
[root@localhost ~]# yum -y install https://www.elrepo.org/elrepo-release-7.0-4.el7.elrepo.noarch.rpm
在有网络的服务器执行打包master
[root@localhost ~]# yum --enablerepo="elrepo-kernel" -y install kernel-ml.x86_64
yum install -enablerepo="elrepo-kernel" kernel-ml.x86_64 --downloadonly --downloaddir=/fw
在有网络的服务器下载完成打包到master
[root@localhost ~]# grub2-set-default 0
[root@localhost ~]# grub2-mkconfig -o /boot/grub2/grub.cfg
2.1.9 Linux内核优化
cat <<EOF > /etc/sysctl.d/k8s.conf
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-iptables = 1
net.bridge.bridge-nf-call-ip6tables = 1
fs.may_detach_mounts = 1
vm.overcommit_memory=1
vm.panic_on_oom=0
fs.inotify.max_user_watches=89100
fs.file-max=52706963
fs.nr_open=52706963
net.netfilter.nf_conntrack_max=2310720
net.ipv4.tcp_keepalive_time = 600
net.ipv4.tcp_keepalive_probes = 3
net.ipv4.tcp_keepalive_intvl =15
net.ipv4.tcp_max_tw_buckets = 36000
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_max_orphans = 327680
net.ipv4.tcp_orphan_retries = 3
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.ip_conntrack_max = 131072
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.tcp_timestamps = 0
net.core.somaxconn = 16384
EOF
sysctl --system
所有节点配置完内核后,重启服务器,保证重启后内核依旧加载
reboot -h now
重启后查看结果:
lsmod | grep --color=auto -e ip_vs -e nf_conntrack
2.1.10 其它工具安装(选装)
yum install wget jq psmisc vim net-tools telnet yum-utils device-mapper-persistent-data lvm2 git lrzsz -y
2.2 负载均衡器准备
2.2.1 安装haproxy与keepalived
yum -y install haproxy keepalived
yum install haproxy keepalived --downloadonly --downloaddir=/fw 同理
2.2.2 HAProxy配置
cat >/etc/haproxy/haproxy.cfg<<"EOF"
global
maxconn 2000
ulimit-n 16384
log 127.0.0.1 local0 err
stats timeout 30s
defaults
log global
mode http
option httplog
timeout connect 5000
timeout client 50000
timeout server 50000
timeout http-request 15s
timeout http-keep-alive 15s
frontend monitor-in
bind *:33305
mode http
option httplog
monitor-uri /monitor
frontend k8s-master
bind 0.0.0.0:6443
bind 127.0.0.1:6443
mode tcp
option tcplog
tcp-request inspect-delay 5s
default_backend k8s-master
backend k8s-master
mode tcp
option tcplog
option tcp-check
balance roundrobin
default-server inter 10s downinter 5s rise 2 fall 2 slowstart 60s maxconn 250 maxqueue 256 weight 100
server k8s-master1 192.168.71.101:6443 check
EOF
2.2.3 KeepAlived
ha:
cat >/etc/keepalived/keepalived.conf<<"EOF"
! Configuration File for keepalived
global_defs {
router_id LVS_DEVEL
script_user root
enable_script_security
}
vrrp_script chk_apiserver {
script "/etc/keepalived/check_apiserver.sh"
interval 5
weight -5
fall 2
rise 1
}
vrrp_instance VI_1 {
state MASTER
interface ens33
mcast_src_ip 192.168.71.104
virtual_router_id 51
priority 100
advert_int 2
authentication {
auth_type PASS
auth_pass K8SHA_KA_AUTH
}
virtual_ipaddress {
192.168.71.100
}
track_script {
chk_apiserver
}
}
EOF
~~~powershell
chmod +x /etc/keepalived/check_apiserver.sh
2.2.5 启动服务并验证
systemctl daemon-reload
systemctl enable --now haproxy
systemctl enable --now keepalived
ip address show
2.3 配置免密登录
在k8s-master1上操作
ssh-keygen
ssh-copy-id root@k8s-master
ssh-copy-id root@k8s-worke1
ssh-copy-id root@k8s-worker2
ssh root@k8s-master1
2.4 部署ETCD集群
在k8s-master上操作。
2.4.1 创建工作目录
mkdir -p /data/k8s-work
2.4.2 获取cfssl工具
cd /data/k8s-work
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 找网络的服务器下载打包到master
说明:
cfssl是使用go编写,由CloudFlare开源的一款PKI/TLS工具。主要程序有:
- cfssl,是CFSSL的命令行工具
- cfssljson用来从cfssl程序获取JSON输出,并将证书,密钥,CSR和bundle写入文件中。
chmod +x cfssl*
mv cfssl_linux-amd64 /usr/local/bin/cfssl
mv cfssljson_linux-amd64 /usr/local/bin/cfssljson
mv cfssl-certinfo_linux-amd64 /usr/local/bin/cfssl-certinfo
# cfssl version
Version: 1.2.0
Revision: dev
Runtime: go1.6
2.4.3 创建CA证书
2.4.3.1 配置ca证书请求文件
cat > ca-csr.json <<"EOF"
{
"CN": "kubernetes",
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "Beijing",
"L": "Beijing",
"O": "kubemsb",
"OU": "CN"
}
],
"ca": {
"expiry": "87600h"
}
}
EOF