Day1-1. kubernetes环境准备

1.1 基础架构#

主机名	角色	IP地址
pg60-11.k8s.host.com	dns/nginx proxy	10.20.60.11
pg60-12.k8s.host.com	dns/nginx proxy	10.20.60.12
pg60-21.k8s.host.com	k8s node1	10.20.60.21
pg60-22.k8s.host.com	k8s node2	10.20.60.22
pg60-23.k8s.host.com	k8s node3	10.20.60.23
pg60-200.k8s.host.com	docker harbor	10.20.60.200

1.2 硬件环境#

• 准备6台虚机环境
• dns/nginx proxy 虚机配置不低于2c/4g/50g
• k8s node 虚机配置不低于4c/8g/50g（运行容器资源的节点，配置越高越好）
• docker harbor 虚机配置不低于2c/4g/50g

1.3 软件环境#

• OS：CentOS Linux release 7.7.1908 (Core)
• BASE源：wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
• EPEL源：wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo

1.4 关闭 swap 分区#

关闭 swap 分区，否则kubelet 会启动失败(可以设置 kubelet 启动参数 --fail-swap-on 为 false 关闭 swap 检查)：

Copy
shell> swapoff -a
shell> sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab

1.5 优化内核参数#

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shell> 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
# 关闭 tcp_tw_recycle，否则与 NAT 冲突，可能导致服务不通；
net.ipv4.tcp_tw_recycle=0
net.ipv4.neigh.default.gc_thresh1=1024
net.ipv4.neigh.default.gc_thresh1=2048
net.ipv4.neigh.default.gc_thresh1=4096
vm.swappiness=0
vm.overcommit_memory=1
vm.panic_on_oom=0
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

shell> modprobe br_netfilter
shell> modprobe nf_conntrack
shell> sysctl -p /etc/sysctl.d/kubernetes.conf

1.6 升级内核#

PS：原因详见《Day1-1. kubernetes环境准备》中的 1.2 升级内核 说明
https://www.cnblogs.com/91donkey/p/13366373.html

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shell> rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm
shell> yum --enablerepo=elrepo-kernel install -y kernel-lt
# 设置开机从新内核启动
shell> grub2-set-default 0
shell> reboot

1.7 更新 PATH 变量#

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shell> echo 'PATH=/opt/etcd/bin:/opt/kubernetes/server/bin/:$PATH' >> /root/.bashrc
shell> source /root/.bashrc