生产级K8S基础环境部署：

• 配置本地hosts文件（有多少台，配置多少台）🐀

vim /etc/hosts
192.168.1.5 k8s-master

• 配置yum源（有自己的yum源更好）🐂

wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo
wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo

• 安装基础工具，配置docker源 🐅

sudo yum install -y yum-utils device-mapper-persistent-data lvm2
sudo yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
sudo sed -i 's+download.docker.com+mirrors.aliyun.com/docker-ce+' /etc/yum.repos.d/docker-ce.repo
sudo yum makecache fast

• 安装一些必备工具 🐇

yum -y install wget jq psmisc vim net-tools  telnet yum-utils device-mapper-persistent-data lvm2 git -y

• 关闭防火墙 🐉

systemctl disable --now firewalld

• 关闭SELinux 🐍

setenforce 0
sed -i 's#SELINUX=enforcing#SELINUX=disabled#g' /etc/sysconfig/selinux

• 关闭交换分区 🐎

swapoff -a && sysctl -w vm.swappiness=0
cat /etc/fstab
# /dev/mapper/centos-swap swap                    swap    defaults        0 0

• 关闭NetworkManager 🐏

systemctl disable --now NetworkManager

• 进行时间同步（有自己的时间服务器更好）🐒

# 安装
rpm -ivh http://mirrors.wlnmp.com/centos/wlnmp-release-centos.noarch.rpm
yum -y install ntpdate
# 同步
ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
echo 'Asia/Shanghai' >/etc/timezone
ntpdate ntp.aliyun.com

crontab -e
crontab -l
*/5 * * * * ntpdate ntp.aliyun.com

• 配置ulimit 🐓

ulimit -SHn 65535
vim /etc/security/limits.conf
* soft nofile 655360
* hard nofile 131072
* soft nproc 655350
* hard nproc 655350
* seft memlock unlimited
* hard memlock unlimitedd

• 配置免密登录（从主master向其他节点分发）🐕

ssh-keygen -t rsa
ssh-copy-id -i .ssh/id_rsa.pub 其他主机

• 升级系统到最新（跳过内核）🐖

yum update -y --exclude=kernel*

• 升级内核至4.18版本以上 o(=•ェ•=)m🐱

cd /root/
wget http://193.49.22.109/elrepo/kernel/el7/x86_64/RPMS/kernel-ml-4.19.12-1.el7.elrepo.x86_64.rpm
wget http://193.49.22.109/elrepo/kernel/el7/x86_64/RPMS/kernel-ml-devel-4.19.12-1.el7.elrepo.x86_64.rpm
yum -y localinstall kernel-ml*
grub2-set-default  0 && grub2-mkconfig -o /etc/grub2.cfg && grubby --args="user_namespace.enable=1" --update-kernel="$(grubby --default-kernel)"
reboot
uname -r

• 安装ipvsadm 🦊

yum install ipvsadm ipset sysstat conntrack libseccomp –y
vim /etc/modules-load.d/ipvs.conf
cat /etc/modules-load.d/ipvs.conf
ip_vs
ip_vs_rr
ip_vs_wrr
ip_vs_sh
nf_conntrack
ip_tables
ip_set
xt_set
ipt_set
ipt_rpfilter
ipt_REJECT
ipip

systemctl enable --now systemd-modules-load.service

lsmod | grep -e ip_vs -e nf_conntrack_ipv4
ip_vs_sh               16384  0
ip_vs_wrr              16384  0
ip_vs_rr               16384  0
ip_vs                 151552  6 ip_vs_rr,ip_vs_sh,ip_vs_wrr
nf_conntrack          143360  1 ip_vs
libcrc32c              16384  3 nf_conntrack,xfs,ip_vs

• 修改内核参数 🐻

cat <<EOF > /etc/sysctl.d/k8s.conf
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-iptables = 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 = 65536
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.tcp_timestamps = 0
net.core.somaxconn = 16384
EOF

sysctl --system

本篇内容只讲K8S部属前的基础环境