[K8s]kubeadm 高可用安装 k8s 集群
1 - 基本环境配置
Kubeadm 安装方式自 1.14 版本以后，安装方法几乎没有任何变化，此文档可以尝试安装最新的 k8s 集群，centos 采用的是 7.x 版本。
K8S官网：https://kubernetes.io/docs/setup/
最新版高可用安装：https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/high-availability/
表1-1 高可用 Kubernetes 集群规划
| 主机名 | IP地址 | 说明 |
|---|---|---|
| k8s-master01 ~ 03 | 192.168.0.107 ~ 203 | master节点 * 3 |
| k8s-master-lb | 192.168.0.236 | keepalived 虚拟IP |
| k8s-node01 ~ 02 | 192.168.0.110 ~ 205 | worker节点 * 2 |
| 配置信息 | 备注 |
|---|---|
| 系统版本 | CentOS 7.9 |
| Docker版本 | 19.03.x |
| Pod网段 | 172.168.0.0/12 |
| Service网段 | 10.96.0.0/12 |
注意
宿主机网段、K8s Service网段、Pod网段不能重复。VIP（虚拟IP）不要和公司内网IP重复，首先去ping一下，不通才可用。VIP需要和主机在同一个局域网内！
公有云上搭建VIP是公有云的负载均衡的IP，比如阿里云的内网SLB的地址，腾讯云内网ELB的地址
所有节点配置hosts，修改/etc/hosts如下：
[root@k8s-master01 ~]# cat /etc/hosts
192.168.0.107 k8s-master01
192.168.0.108 k8s-master02
192.168.0.109 k8s-master03
192.168.0.236 k8s-master-lb # 如果不是高可用集群，该IP为Master01的IP
192.168.0.110 k8s-node01
192.168.0.111 k8s-node02
CentOS 7 安装yum源如下：
curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
必备工具安装
yum install wget jq psmisc vim net-tools telnet yum-utils device-mapper-persistent-data lvm2 git -y
所有节点关闭防火墙、selinux、dnsmasq、swap。服务器配置如下：
systemctl disable --now firewalld
systemctl disable --now dnsmasq
systemctl disable --now NetworkManager
setenforce 0
sed -i 's#SELINUX=enforcing#SELINUX=disabled#g' /etc/sysconfig/selinux
sed -i 's#SELINUX=enforcing#SELINUX=disabled#g' /etc/selinux/config
关闭swap分区
swapoff -a && sysctl -w vm.swappiness=0
sed -ri '/^[^#]*swap/s@^@#@' /etc/fstab
安装ntpdate
rpm -ivh http://mirrors.wlnmp.com/centos/wlnmp-release-centos.noarch.rpm
yum install ntpdate -y
所有节点同步时间。时间同步配置如下：
ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
echo 'Asia/Shanghai' >/etc/timezone
ntpdate time2.aliyun.com
# 加入到crontab
*/5 * * * * /usr/sbin/ntpdate time2.aliyun.com
所有节点配置limit：
ulimit -SHn 65535
vim /etc/security/limits.conf
# 末尾添加如下内容
* soft nofile 65536
* hard nofile 131072
* soft nproc 65535
* hard nproc 655350
* soft memlock unlimited
* hard memlock unlimited
Master01 节点免密钥登录其他节点，安装过程中生成配置文件和证书均在 Master01 上操作，集群管理也在 Master01 上操作，阿里云或者 AWS 上需要单独一台 kubectl 服务器。密钥配置如下：
ssh-keygen -t rsa
for i in k8s-master01 k8s-master02 k8s-master03 k8s-node01 k8s-node02;do ssh-copy-id -i .ssh/id_rsa.pub $i;done
下载安装所有的源码文件：
cd /root/ ; git clone https://github.com/dotbalo/k8s-ha-install.git
所有节点升级系统并重启，此处升级没有升级内核，下节会单独升级内核：
yum update -y --exclude=kernel* && reboot #CentOS7需要升级，CentOS8可以按需升级系统
2 - 内核配置
CentOS7 需要升级内核至 4.18+，本地升级的版本为 4.19。
在master01节点下载内核：
cd /root
wget http://193.49.22.109/elrepo/kernel/el7/x86_64/RPMS/kernel-ml-devel-4.19.12-1.el7.elrepo.x86_64.rpm
wget http://193.49.22.109/elrepo/kernel/el7/x86_64/RPMS/kernel-ml-4.19.12-1.el7.elrepo.x86_64.rpm
从master01节点传到其他节点：
for i in k8s-master02 k8s-master03 k8s-node01 k8s-node02;do scp kernel-ml-4.19.12-1.el7.elrepo.x86_64.rpm kernel-ml-devel-4.19.12-1.el7.elrepo.x86_64.rpm $i:/root/ ; done
所有节点安装内核
cd /root && yum localinstall -y kernel-ml*
所有节点更改内核启动顺序
grub2-set-default 0 && grub2-mkconfig -o /etc/grub2.cfg
grubby --args="user_namespace.enable=1" --update-kernel="$(grubby --default-kernel)"
检查默认内核是不是4.19
[root@k8s-master02 ~]# grubby --default-kernel
/boot/vmlinuz-4.19.12-1.el7.elrepo.x86_64
所有节点重启，然后检查内核是不是4.19
[root@k8s-master02 ~]# uname -a
Linux k8s-master02 4.19.12-1.el7.elrepo.x86_64 #1 SMP Fri Dec 21 11:06:36 EST 2018 x86_64 x86_64 x86_64 GNU/Linux
所有节点安装ipvsadm：
yum install ipvsadm ipset sysstat conntrack libseccomp -y
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
vim /etc/modules-load.d/ipvs.conf
#加入以下内容
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
然后执行systemctl enable --now systemd-modules-load.service即可。
开启一些 k8s 集群中必须的内核参数，所有节点配置 k8s 内核：
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 = 65536
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
lsmod | grep --color=auto -e ip_vs -e nf_conntrack
3 - 基本组件安装
本节主要安装的是集群中用到的各种组件，比如 Docker-ce、Kubernetes 各组件等。
所有节点安装 Docker-ce 19.03：
yum install docker-ce-19.03.* docker-cli-19.03.* -y
温馨提示：
由于新版 kubelet 建议使用 systemd，所以可以把 docker 的 CgroupDriver 改成 systemd。
mkdir /etc/docker
cat > /etc/docker/daemon.json <<EOF
{
"exec-opts": ["native.cgroupdriver=systemd"]
}
EOF
所有节点设置开机自启动 Docker：
systemctl daemon-reload && systemctl enable --now docker
安装 k8s 组件：
yum list kubeadm.x86_64 --showduplicates | sort -r
所有节点安装最新版本 kubeadm：
yum install kubeadm-1.20* kubelet-1.20* kubectl-1.20* -y
默认配置的pause镜像使用gcr.io仓库，国内可能无法访问，所以这里配置 Kubelet 使用阿里云的pause镜像：
cat >/etc/sysconfig/kubelet<<EOF
KUBELET_EXTRA_ARGS="--cgroup-driver=systemd --pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google_containers/pause-amd64:3.2"
EOF
设置 Kubelet 开机自启动：
systemctl daemon-reload
systemctl enable --now kubelet
4 - 高可用组件安装
（注意： 如果不是高可用集群，haproxy和keepalived无需安装）
公有云要用公有云自带的负载均衡，比如阿里云的SLB，腾讯云的ELB，用来替代haproxy和keepalived，因为公有云大部分都是不支持keepalived的，另外如果用阿里云的话，kubectl控制端不能放在master节点，推荐使用腾讯云，因为阿里云的slb有回环的问题，也就是slb代理的服务器不能反向访问SLB，但是腾讯云修复了这个问题。
所有 Master 节点通过 yum 安装 HAProxy 和 KeepAlived：
yum install keepalived haproxy -y
所有 Master 节点配置 HAProxy（所有 Master 节点的 HAProxy 配置相同）：
[root@k8s-master01 etc]# mkdir /etc/haproxy
[root@k8s-master01 etc]# vim /etc/haproxy/haproxy.cfg
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 0.0.0.0:16443
bind 127.0.0.1:16443
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-master01 192.168.0.107:6443 check
server k8s-master02 192.168.0.108:6443 check
server k8s-master03 192.168.0.109:6443 check
所有 Master 节点配置 KeepAlived，配置不一样，注意区分 [root@k8s-master01 pki]# vim /etc/keepalived/keepalived.conf，注意每个节点的IP和网卡（interface参数）
Master01 节点的配置：
[root@k8s-master01 etc]# mkdir /etc/keepalived
[root@k8s-master01 ~]# vim /etc/keepalived/keepalived.conf
! 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 192.168.0.107
virtual_router_id 51
priority 101
advert_int 2
authentication {
auth_type PASS
auth_pass K8SHA_KA_AUTH
}
virtual_ipaddress {
192.168.0.236
}
track_script {
chk_apiserver
}
}
Master02 节点的配置：
! 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 BACKUP
interface ens33
mcast_src_ip 192.168.0.108
virtual_router_id 51
priority 100
advert_int 2
authentication {
auth_type PASS
auth_pass K8SHA_KA_AUTH
}
virtual_ipaddress {
192.168.0.236
}
track_script {
chk_apiserver
}
}
Master03 节点的配置：
! 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 BACKUP
interface ens33
mcast_src_ip 192.168.0.109
virtual_router_id 51
priority 100
advert_int 2
authentication {
auth_type PASS
auth_pass K8SHA_KA_AUTH
}
virtual_ipaddress {
192.168.0.236
}
track_script {
chk_apiserver
}
}
所有master节点配置 KeepAlived 健康检查文件：
[root@k8s-master01 keepalived]# cat /etc/keepalived/check_apiserver.sh
#!/bin/bash
err=0
for k in $(seq 1 3)
do
check_code=$(pgrep haproxy)
if [[ $check_code == "" ]]; then
err=$(expr $err + 1)
sleep 1
continue
else
err=0
break
fi
done
if [[ $err != "0" ]]; then
echo "systemctl stop keepalived"
/usr/bin/systemctl stop keepalived
exit 1
else
exit 0
fi
chmod +x /etc/keepalived/check_apiserver.sh
启动 haproxy 和 keepalived
[root@k8s-master01 keepalived]# systemctl daemon-reload
[root@k8s-master01 keepalived]# systemctl enable --now haproxy
[root@k8s-master01 keepalived]# systemctl enable --now keepalived
重要： 如果安装了keepalived和haproxy，需要测试keepalived是否是正常的。
测试VIP
[root@k8s-master01 ~]# ping 192.168.0.236 -c 4
PING 192.168.0.236 (192.168.0.236) 56(84) bytes of data.
64 bytes from 192.168.0.236: icmp_seq=1 ttl=64 time=0.464 ms
64 bytes from 192.168.0.236: icmp_seq=2 ttl=64 time=0.063 ms
64 bytes from 192.168.0.236: icmp_seq=3 ttl=64 time=0.062 ms
64 bytes from 192.168.0.236: icmp_seq=4 ttl=64 time=0.063 ms
--- 192.168.0.236 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3106ms
rtt min/avg/max/mdev = 0.062/0.163/0.464/0.173 ms
[root@k8s-master01 ~]# telnet 192.168.0.236 16443
Trying 192.168.0.236...
Connected to 192.168.0.236.
Escape character is '^]'.
Connection closed by foreign host.
如果ping不通且telnet没有出现 ]，则认为VIP不可以，不可在继续往下执行，需要排查 keepalived 的问题，比如防火墙和selinux，haproxy和keepalived的状态，监听端口等。
所有节点查看防火墙状态必须为disable和inactive：systemctl status firewalld
所有节点查看selinux状态，必须为disable：getenforce
master节点查看haproxy和keepalived状态：systemctl status keepalived haproxy
master节点查看监听端口：netstat -lntp
5 - 集群初始化
官方初始化文档：
https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/high-availability/
Master01节点创建kubeadm-config.yaml配置文件如下：
Master01：（注意，如果不是高可用集群，192.168.0.236:16443改为master01的地址，16443改为apiserver的端口，默认是6443，注意更改v1.18.5自己服务器 kubeadm 的版本：kubeadm version）
注意
以下文件内容，宿主机网段、podSubnet网段、serviceSubnet网段不能重复
apiVersion: kubeadm.k8s.io/v1beta2
bootstrapTokens:
- groups:
- system:bootstrappers:kubeadm:default-node-token
token: 7t2weq.bjbawausm0jaxury
ttl: 24h0m0s
usages:
- signing
- authentication
kind: InitConfiguration
localAPIEndpoint:
advertiseAddress: 192.168.0.107
bindPort: 6443
nodeRegistration:
criSocket: /var/run/dockershim.sock
name: k8s-master01
taints:
- effect: NoSchedule
key: node-role.kubernetes.io/master
---
apiServer:
certSANs:
- 192.168.0.236
timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta2
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controlPlaneEndpoint: 192.168.0.236:16443
controllerManager: {}
dns:
type: CoreDNS
etcd:
local:
dataDir: /var/lib/etcd
imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers
kind: ClusterConfiguration
kubernetesVersion: v1.20.0
networking:
dnsDomain: cluster.local
podSubnet: 172.168.0.0/12
serviceSubnet: 10.96.0.0/12
scheduler: {}
更新kubeadm文件
kubeadm config migrate --old-config kubeadm-config.yaml --new-config new.yaml
将new.yaml文件复制到其他master节点，之后所有Master节点提前下载镜像，可以节省初始化时间：
kubeadm config images pull --config /root/new.yaml
所有节点设置开机自启动 kubelet
systemctl enable --now kubelet（如果启动失败无需管理，初始化成功以后即可启动）
Master01节点初始化，初始化以后会在/etc/kubernetes目录下生成对应的证书和配置文件，之后其他Master节点加入Master01即可：
kubeadm init --config /root/new.yaml --upload-certs
如果初始化失败，重置后再次初始化，命令如下：
kubeadm reset -f ; ipvsadm --clear ; rm -rf ~/.kube
初始化成功以后，会产生Token值，用于其他节点加入时使用，因此要记录下初始化成功生成的token值（令牌值）：
Your Kubernetes control-plane has initialized successfully!
To start using your cluster, you need to run the following as a regular user:
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
Alternatively, if you are the root user, you can run:
export KUBECONFIG=/etc/kubernetes/admin.conf
You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
https://kubernetes.io/docs/concepts/cluster-administration/addons/
You can now join any number of the control-plane node running the following command on each as root:
kubeadm join 192.168.0.236:16443 --token 7t2weq.bjbawausm0jaxury \
--discovery-token-ca-cert-hash sha256:3d910c87e31745563b0d8138fa6f4e99afd83bd8236d9a5d002b0cfde0d9f839 \
--control-plane --certificate-key 3c6de42b03757042138bfeb2bf4c3dcd4890b17f6b7e166fdf0ae46081783b31
Please note that the certificate-key gives access to cluster sensitive data, keep it secret!
As a safeguard, uploaded-certs will be deleted in two hours; If necessary, you can use
"kubeadm init phase upload-certs --upload-certs" to reload certs afterward.
Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 192.168.0.236:16443 --token 7t2weq.bjbawausm0jaxury \
--discovery-token-ca-cert-hash sha256:3d910c87e31745563b0d8138fa6f4e99afd83bd8236d9a5d002b0cfde0d9f839
Master01节点配置环境变量，用于访问Kubernetes集群：
cat <<EOF >> /root/.bashrc
export KUBECONFIG=/etc/kubernetes/admin.conf
EOF
source /root/.bashrc
查看节点状态：
[root@k8s-master01 ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master01 NotReady control-plane,master 74s v1.20.0
采用初始化安装方式，所有的系统组件均以容器的方式运行并且在kube-system命名空间内，此时可以查看Pod状态：
[root@k8s-master01 ~]# kubectl get pods -n kube-system -o wide
NAME READY STATUS RESTARTS AGE IP NODE
coredns-777d78ff6f-kstsz 0/1 Pending 0 14m <none> <none>
coredns-777d78ff6f-rlfr5 0/1 Pending 0 14m <none> <none>
etcd-k8s-master01 1/1 Running 0 14m 192.168.0.107 k8s-master01
kube-apiserver-k8s-master01 1/1 Running 0 13m 192.168.0.107 k8s-master01
kube-controller-manager-k8s-master01 1/1 Running 0 13m 192.168.0.107 k8s-master01
kube-proxy-8d4qc 1/1 Running 0 14m 192.168.0.107 k8s-master01
kube-scheduler-k8s-master01 1/1 Running 0 13m 192.168.0.107 k8s-master01
6 - 高可用 Master
注意： 以下步骤是上述init命令产生的Token过期了才需要执行以下步骤，如果没有过期不需要执行
Token过期后生成新的token：
kubeadm token create --print-join-command
Master需要生成 --certificate-key
kubeadm init phase upload-certs --upload-certs
Token没有过期直接执行Join就行了
初始化其他master加入集群
kubeadm join 192.168.0.236:16443 --token wzb8hf.7j101pwv8q9i180r --discovery-token-ca-cert-hash sha256:3d910c87e31745563b0d8138fa6f4e99afd83bd8236d9a5d002b0cfde0d9f839 \
--control-plane --certificate-key b69b4cd9f2d0fc531f524ae0924de1c0845c925a3e703630fac31966c17e3d15
7 - Node 节点的配置
Node节点上主要部署公司的一些业务应用，生产环境中不建议Master节点部署系统组件之外的其他Pod，测试环境可以允许Master节点部署Pod以节省系统资源。
kubeadm join 192.168.0.236:16443 --token 7t2weq.bjbawausm0jaxury \
--discovery-token-ca-cert-hash sha256:8c92ecb336be2b9372851a9af2c7ca1f7f60c12c68f6ffe1eb513791a1b8a908
所有节点初始化完成后，查看集群状态
[root@k8s-master01]# kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master01 NotReady control-plane,master 8m53s v1.20.0
k8s-master02 NotReady control-plane,master 2m25s v1.20.0
k8s-master03 NotReady control-plane,master 31s v1.20.0
k8s-node01 NotReady <none> 32s v1.20.0
k8s-node02 NotReady <none> 88s v1.20.0
8 - Calico 组件的安装
以下步骤只在master01执行
cd /root/k8s-ha-install && git checkout manual-installation-v1.20.x && cd calico/
修改calico-etcd.yaml的以下位置
sed -i 's#etcd_endpoints: "http://<ETCD_IP>:<ETCD_PORT>"#etcd_endpoints: "https://192.168.0.107:2379,https://192.168.0.108:2379,https://192.168.0.109:2379"#g' calico-etcd.yaml
ETCD_CA=`cat /etc/kubernetes/pki/etcd/ca.crt | base64 | tr -d '\n'`
ETCD_CERT=`cat /etc/kubernetes/pki/etcd/server.crt | base64 | tr -d '\n'`
ETCD_KEY=`cat /etc/kubernetes/pki/etcd/server.key | base64 | tr -d '\n'`
sed -i "s@# etcd-key: null@etcd-key: ${ETCD_KEY}@g; s@# etcd-cert: null@etcd-cert: ${ETCD_CERT}@g; s@# etcd-ca: null@etcd-ca: ${ETCD_CA}@g" calico-etcd.yaml
sed -i 's#etcd_ca: ""#etcd_ca: "/calico-secrets/etcd-ca"#g; s#etcd_cert: ""#etcd_cert: "/calico-secrets/etcd-cert"#g; s#etcd_key: "" #etcd_key: "/calico-secrets/etcd-key" #g' calico-etcd.yaml
POD_SUBNET=`cat /etc/kubernetes/manifests/kube-controller-manager.yaml | grep cluster-cidr= | awk -F= '{print $NF}'`
注意下面的这个步骤是把calico-etcd.yaml文件里面的CALICO_IPV4POOL_CIDR下的网段改成自己的Pod网段，也就是把192.168.x.x/16改成自己的集群网段，并打开注释：
所以更改的时候请确保这个步骤的这个网段没有被统一替换掉，如果被替换掉了，还请改回来：
sed -i 's@# - name: CALICO_IPV4POOL_CIDR@- name: CALICO_IPV4POOL_CIDR@g; s@# value: "192.168.0.0/16"@ value: '"${POD_SUBNET}"'@g' calico-etcd.yaml
kubectl apply -f calico-etcd.yaml
查看容器状态
[root@k8s-master01 calico]# kubectl get po -n kube-system
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-5f6d4b864b-pwvnb 1/1 Running 0 3m29s
calico-node-5lz9m 1/1 Running 0 3m29s
calico-node-8z4bg 1/1 Running 0 3m29s
calico-node-lmzvf 1/1 Running 0 3m29s
calico-node-mpngv 1/1 Running 0 3m29s
calico-node-vmqsl 1/1 Running 0 3m29s
coredns-54d67798b7-8525g 1/1 Running 0 39m
coredns-54d67798b7-fxs72 1/1 Running 0 39m
etcd-k8s-master01 1/1 Running 0 39m
etcd-k8s-master02 1/1 Running 0 33m
etcd-k8s-master03 1/1 Running 0 31m
kube-apiserver-k8s-master01 1/1 Running 0 39m
kube-apiserver-k8s-master02 1/1 Running 0 33m
kube-apiserver-k8s-master03 1/1 Running 0 30m
kube-controller-manager-k8s-master01 1/1 Running 1 39m
kube-controller-manager-k8s-master02 1/1 Running 0 33m
kube-controller-manager-k8s-master03 1/1 Running 0 31m
kube-proxy-hnkmj 1/1 Running 0 39m
kube-proxy-jk4dm 1/1 Running 0 32m
kube-proxy-nbcg2 1/1 Running 0 32m
kube-proxy-qv9k7 1/1 Running 0 32m
kube-proxy-x6xdc 1/1 Running 0 33m
kube-scheduler-k8s-master01 1/1 Running 1 39m
kube-scheduler-k8s-master02 1/1 Running 0 33m
kube-scheduler-k8s-master03 1/1 Running 0 30m
9 - Metrics 部署
在新版的Kubernetes中系统资源的采集均使用Metrics-server，可以通过Metrics采集节点和Pod的内存、磁盘、CPU和网络的使用率。
将Master01节点的front-proxy-ca.crt复制到所有Node节点：
scp /etc/kubernetes/pki/front-proxy-ca.crt k8s-node01:/etc/kubernetes/pki/front-proxy-ca.crt
scp /etc/kubernetes/pki/front-proxy-ca.crt k8s-node(其他节点自行拷贝):/etc/kubernetes/pki/front-proxy-ca.crt
安装 metrics server
cd /root/k8s-ha-install/metrics-server-0.4.x-kubeadm/
[root@k8s-master01 metrics-server-0.4.x-kubeadm]# kubectl create -f comp.yaml
serviceaccount/metrics-server created
clusterrole.rbac.authorization.k8s.io/system:aggregated-metrics-reader created
clusterrole.rbac.authorization.k8s.io/system:metrics-server created
rolebinding.rbac.authorization.k8s.io/metrics-server-auth-reader created
clusterrolebinding.rbac.authorization.k8s.io/metrics-server:system:auth-delegator created
clusterrolebinding.rbac.authorization.k8s.io/system:metrics-server created
service/metrics-server created
deployment.apps/metrics-server created
apiservice.apiregistration.k8s.io/v1beta1.metrics.k8s.io created
查看状态
[root@k8s-master01 metrics-server-0.4.x-kubeadm]# kubectl top node
NAME CPU(cores) CPU% MEMORY(bytes) MEMORY%
k8s-master01 109m 2% 1296Mi 33%
k8s-master02 99m 2% 1124Mi 29%
k8s-master03 104m 2% 1082Mi 28%
k8s-node01 55m 1% 761Mi 19%
k8s-node02 53m 1% 663Mi 17%
10 - Dashboard 部署
Dashboard用于展示集群中的各类资源，同时也可以通过Dashboard实时查看Pod的日志和在容器中执行一些命令等。
10.1 安装指定版本 dashboard
cd /root/k8s-ha-install/dashboard/
[root@k8s-master01 dashboard]# kubectl create -f .
serviceaccount/admin-user created
clusterrolebinding.rbac.authorization.k8s.io/admin-user created
namespace/kubernetes-dashboard created
serviceaccount/kubernetes-dashboard created
service/kubernetes-dashboard created
secret/kubernetes-dashboard-certs created
secret/kubernetes-dashboard-csrf created
secret/kubernetes-dashboard-key-holder created
configmap/kubernetes-dashboard-settings created
role.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrole.rbac.authorization.k8s.io/kubernetes-dashboard created
rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
deployment.apps/kubernetes-dashboard created
service/dashboard-metrics-scraper created
deployment.apps/dashboard-metrics-scraper created
10.2 安装最新版
官方GitHub地址：https://github.com/kubernetes/dashboard
可以在官方dashboard查看到最新版dashboard
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.3/aio/deploy/recommended.yaml
创建管理员用户
vim admin.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
name: admin-user
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: admin-user
annotations:
rbac.authorization.kubernetes.io/autoupdate: "true"
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: cluster-admin
subjects:
- kind: ServiceAccount
name: admin-user
namespace: kube-system
kubectl apply -f admin.yaml -n kube-system
10.3 登录 dashboard
在谷歌浏览器（Chrome）启动文件中加入启动参数，用于解决无法访问Dashboard的问题，参考图1-1：
--test-type --ignore-certificate-errors
图1-1 谷歌浏览器 Chrome的配置
更改dashboard的svc为NodePort：
kubectl edit svc kubernetes-dashboard -n kubernetes-dashboard
将ClusterIP更改为NodePort（如果已经为NodePort忽略此步骤）
查看端口号：
kubectl get svc kubernetes-dashboard -n kubernetes-dashboard
根据自己的实例端口号，通过任意安装了kube-proxy的宿主机或者VIP的IP+端口即可访问到dashboard：
访问Dashboard：https://192.168.0.236:18282（请更改18282为自己的端口），选择登录方式为令牌（即token方式），参考图1-2
图1-2 Dashboard登录方式
查看token值：
[root@k8s-master01 1.1.1]# kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}')
Name: admin-user-token-8q49g
Namespace: kube-system
Labels: <none>
Annotations: kubernetes.io/service-account.name: admin-user
kubernetes.io/service-account.uid: 1e97290f-f826-43fd-8b6b-742ab5d76dab
Type: kubernetes.io/service-account-token
Data
====
ca.crt: 1066 bytes
namespace: 11 bytes
token: eyJhbGciOiJSUzI1NiIsImtpZCI6Ino3aEp5b2pjcFFDVy1hQkI1Z25xQkx3dGJ3UHhWUXFMMzc5Q0tzQnJyYlkifQ.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJhZG1pbi11c2VyLXRva2VuLThxNDlnIiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZXJ2aWNlLWFjY291bnQubmFtZSI6ImFkbWluLXVzZXIiLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiIxZTk3MjkwZi1mODI2LTQzZmQtOGI2Yi03NDJhYjVkNzZkYWIiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6a3ViZS1zeXN0ZW06YWRtaW4tdXNlciJ9.FO8OI3nu8F1v8uj8UItMqbFae76lnD-m5v6GLQaKPRVJszNHIQdlE8cu6p_PA0M0r7QPZ_YUhtP5wlpBuoXAdiva_CB0-LtGUszo7UyyHL6ZVcX48QpIEe7cG7IbO4hsGX03oUUqMfQKnTTepnNf4HZEj8UnGi8tANelIypeMpvzHDAcfuHUha1Sy2tCafHmivH6FVUo8CqC7IGpy5BJYU8RJBJNmJES2CMMWFp8vNo4YBJi05sghN66ecazDt5k2s41ld8lKXpwneBuhkkdF-4RVJwiyHW15_LGW7G4eSWr4_9WuTW8Xvkm_-oPPMoSR1u_Gbl4vSQ1pbK5UyaEbg
将token值输入到令牌后，单击登录即可访问Dashboard，参考图1-3：
图1-3 Dashboard页面
11 - 一些必须的配置更改
将Kube-proxy改为ipvs模式，因为在初始化集群的时候注释了ipvs配置，所以需要自行修改一下：
在master01节点执行
kubectl edit cm kube-proxy -n kube-system
mode: “ipvs”
更新Kube-Proxy的Pod：
kubectl patch daemonset kube-proxy -p "{\"spec\":{\"template\":{\"metadata\":{\"annotations\":{\"date\":\"`date +'%s'`\"}}}}}" -n kube-system
验证Kube-Proxy模式
[root@k8s-master01 1.1.1]# curl 127.0.0.1:10249/proxyMode
ipvs
12 - 注意事项
注意： kubeadm安装的集群，证书有效期默认是一年。master节点的kube-apiserver、kube-scheduler、kube-controller-manager、etcd都是以容器运行的。可以通过kubectl get po -n kube-system查看。
启动和二进制不同的是，kubelet的配置文件在/etc/sysconfig/kubelet和/var/lib/kubelet/config.yaml，修改后需要重启kubelet进程。
其他组件的配置文件在/etc/kubernetes/manifests目录下，比如kube-apiserver.yaml，该yaml文件更改后，kubelet会自动刷新配置，也就是会重启pod。不能再次创建该文件
kube-proxy的配置在kube-system命名空间下的configmap中，可以通过：
kubectl edit cm kube-proxy -n kube-system
进行更改更改完成后，可以通过patch重启kube-proxy
kubectl patch daemonset kube-proxy -p "{\"spec\":{\"template\":{\"metadata\":{\"annotations\":{\"date\":\"`date +'%s'`\"}}}}}" -n kube-system
Kubeadm安装后，master节点默认不允许部署pod，可以通过以下方式打开
查看Taints：
[root@k8s-master01 ~]# kubectl describe node -l node-role.kubernetes.io/master= | grep Taints
Taints: node-role.kubernetes.io/master:NoSchedule
Taints: node-role.kubernetes.io/master:NoSchedule
Taints: node-role.kubernetes.io/master:NoSchedule
删除Taint：
[root@k8s-master01 ~]# kubectl taint node -l node-role.kubernetes.io/master node-role.kubernetes.io/master:NoSchedule-
node/k8s-master01 untainted
node/k8s-master02 untainted
node/k8s-master03 untainted
[root@k8s-master01 ~]# kubectl describe node -l node-role.kubernetes.io/master= | grep Taints
Taints: <none>
Taints: <none>
Taints: <none>
