ubuntu18 多master集群化部署k8s-1.11

实验环境说明
实验架构图
lab1: etcd master haproxy keepalived 11.11.11.111
lab2: etcd master haproxy keepalived 11.11.11.112
lab3: etcd master haproxy keepalived 11.11.11.113
lab4: node 11.11.11.114
lab5: node 11.11.11.115
lab6: node 11.11.11.116

vip(loadblancer ip): 11.11.11.110

实验使用的Vagrantfile

-- mode: ruby --

vi: set ft=ruby :

ENV[“LC_ALL”] = “en_US.UTF-8”

Vagrant.configure(“2”) do |config|
(1…6).each do |i|
config.vm.define “lab#{i}” do |node|
node.vm.box = “centos-7.4-docker-17”
node.ssh.insert_key = false
node.vm.hostname = “lab#{i}”
node.vm.network “private_network”, ip: “11.11.11.11#{i}”
node.vm.provision “shell”,
inline: “echo hello from node #{i}”
node.vm.provider “virtualbox” do |v|
v.cpus = 2
v.customize [“modifyvm”, :id, “–name”, “lab#{i}”, “–memory”, “2048”]
end
end
end
end

安装配置docker
v1.11.0版本推荐使用docker v17.03,
v1.11,v1.12,v1.13, 也可以使用，再高版本的docker可能无法正常使用。
测试发现17.09无法正常使用，不能使用资源限制(内存CPU)
如下操作在所有节点操作

安装docker

卸载安装指定版本docker-ce

apt-get install -y docker-ce=18.06.1_ce3-0~ubuntu

启动docker
systemctl enable docker && systemctl restart docker

安装 kubeadm, kubelet 和 kubectl
如下操作在所有节点操作

使用阿里镜像安装

配置源

cat < /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

安装

apt-get install -y kubelet=1.11.0-00 kubectl=1.11.0-00 kubeadm=1.11.0-00

配置系统相关参数

临时禁用selinux

永久关闭 修改/etc/sysconfig/selinux文件设置

sed -i ‘s/SELINUX=permissive/SELINUX=disabled/’ /etc/sysconfig/selinux
setenforce 0

临时关闭swap

永久关闭 注释/etc/fstab文件里swap相关的行

swapoff -a

开启forward

Docker从1.13版本开始调整了默认的防火墙规则

禁用了iptables filter表中FOWARD链

这样会引起Kubernetes集群中跨Node的Pod无法通信

iptables -P FORWARD ACCEPT

配置转发相关参数，否则可能会出错

cat < /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
vm.swappiness=0
EOF
sysctl --system

加载ipvs相关内核模块

如果重新开机，需要重新加载

modprobe ip_vs
modprobe ip_vs_rr
modprobe ip_vs_wrr
modprobe ip_vs_sh
modprobe nf_conntrack_ipv4
lsmod | grep ip_vs

配置hosts解析
如下操作在所有节点操作
cat >>/etc/hosts< 11.11.11.111 lab1
11.11.11.112 lab2
11.11.11.113 lab3
11.11.11.114 lab4
11.11.11.115 lab5
11.11.11.116 lab6
EOF

配置haproxy代理和keepalived
如下操作在节点lab1,lab2,lab3操作

拉取haproxy镜像

docker pull haproxy:1.7.8-alpine
mkdir /etc/haproxy
cat >/etc/haproxy/haproxy.cfg< global
log 127.0.0.1 local0 err
maxconn 50000
uid 99
gid 99
#daemon
nbproc 1
pidfile haproxy.pid

defaults
mode http
log 127.0.0.1 local0 err
maxconn 50000
retries 3
timeout connect 5s
timeout client 30s
timeout server 30s
timeout check 2s

listen admin_stats
mode http
bind 0.0.0.0:1080
log 127.0.0.1 local0 err
stats refresh 30s
stats uri /haproxy-status
stats realm Haproxy\ Statistics
stats auth will:will
stats hide-version
stats admin if TRUE

frontend k8s-https
bind 0.0.0.0:8443
mode tcp
#maxconn 50000
default_backend k8s-https

backend k8s-https
mode tcp
balance roundrobin
server lab1 11.11.11.111:6443 weight 1 maxconn 1000 check inter 2000 rise 2 fall 3
server lab2 11.11.11.112:6443 weight 1 maxconn 1000 check inter 2000 rise 2 fall 3
server lab3 11.11.11.113:6443 weight 1 maxconn 1000 check inter 2000 rise 2 fall 3
EOF

启动haproxy

docker run -d --name my-haproxy
-v /etc/haproxy:/usr/local/etc/haproxy:ro
-p 8443:8443
-p 1080:1080
–restart always
haproxy:1.7.8-alpine

查看日志

docker logs my-haproxy

浏览器查看状态

http://11.11.11.111:1080/haproxy-status
http://11.11.11.112:1080/haproxy-status

拉取keepalived镜像

docker pull osixia/keepalived:1.4.4

启动

载入内核相关模块

lsmod | grep ip_vs
modprobe ip_vs

启动keepalived

eth1为本次实验11.11.11.0/24网段的所在网卡

docker run --net=host --cap-add=NET_ADMIN
-e KEEPALIVED_INTERFACE=eth1
-e KEEPALIVED_VIRTUAL_IPS="#PYTHON2BASH:[‘11.11.11.110’]"
-e KEEPALIVED_UNICAST_PEERS="#PYTHON2BASH:[‘11.11.11.111’,‘11.11.11.112’,‘11.11.11.113’]"
-e KEEPALIVED_PASSWORD=hello
–name k8s-keepalived
–restart always
-d osixia/keepalived:1.4.4

查看日志

会看到两个成为backup 一个成为master

docker logs k8s-keepalived

此时会配置 11.11.11.110 到其中一台机器

ping测试

ping -c4 11.11.11.110

如果失败后清理后，重新实验

docker rm -f k8s-keepalived
ip a del 11.11.11.110/32 dev eth1

配置启动kubelet
如下操作在所有节点操作

配置kubelet使用国内pause镜像

配置kubelet的cgroups

获取docker的cgroups

DOCKER_CGROUPS=$(docker info | grep ‘Cgroup’ | cut -d’ ’ -f3)
echo $DOCKE{R}_{C}GROUPScat>/etc/sysconfig/kubelet<<EOFKUBELE{T}_{E}XTR{A}_{A}RGS="--cgroup-driver=$DOCKER_CGROUPS --pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google_containers/pause-amd64:3.1"
EOF

启动

systemctl daemon-reload
systemctl enable kubelet && systemctl restart kubelet

配置master
配置第一个master节点
如下操作在lab1节点操作

1.11 版本 centos 下使用 ipvs 模式会出问题

参考 https://github.com/kubernetes/kubernetes/issues/65461

生成配置文件

CP0_IP=“11.11.11.111”
CP0_HOSTNAME=“lab1”
cat >kubeadm-master.config< apiVersion: kubeadm.k8s.io/v1alpha2
kind: MasterConfiguration
kubernetesVersion: v1.11.0
imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers

apiServerCertSANs:

• “lab1”
• “lab2”
• “lab3”
• “11.11.11.111”
• “11.11.11.112”
• “11.11.11.113”
• “11.11.11.110”
• “127.0.0.1”

api:
advertiseAddress: $CP0_IP
controlPlaneEndpoint: 11.11.11.110:8443

etcd:
local:
extraArgs:
listen-client-urls: “https://127.0.0.1:2379,https://$CP{0}_{I}P:2379"advertise-client-urls:"https://$CP0_IP:2379”
listen-peer-urls: “https://$CP{0}_{I}P:2380"initial-advertise-peer-urls:"https://$CP0_IP:2380”
initial-cluster: “$CP{0}_{H}OSTNAME=https://$CP0_IP:2380”
serverCertSANs:
- $CP0_HOSTNAME
- $CP0_IP
peerCertSANs:
- $CP0_HOSTNAME
- $CP0_IP

controllerManagerExtraArgs:
node-monitor-grace-period: 10s
pod-eviction-timeout: 10s

networking:
podSubnet: 10.244.0.0/16

kubeProxy:
config:
# mode: ipvs
mode: iptables
EOF

提前拉取镜像

如果执行失败 可以多次执行

kubeadm config images pull --config kubeadm-master.config

初始化

注意保存返回的 join 命令

kubeadm init --config kubeadm-master.config

打包ca相关文件上传至其他master节点

cd /etc/kubernetes && tar cvzf k8s-key.tgz admin.conf pki/ca.* pki/sa.* pki/front-proxy-ca.* pki/etcd/ca.*
scp k8s-key.tgz lab2:~/
scp k8s-key.tgz lab3:~/
ssh lab2 ‘tar xf k8s-key.tgz -C /etc/kubernetes/’
ssh lab3 ‘tar xf k8s-key.tgz -C /etc/kubernetes/’

配置第二个master节点
如下操作在lab2节点操作

1.11 版本 centos 下使用 ipvs 模式会出问题

参考 https://github.com/kubernetes/kubernetes/issues/65461

生成配置文件

CP0_IP=“11.11.11.111”
CP0_HOSTNAME=“lab1”
CP1_IP=“11.11.11.112”
CP1_HOSTNAME=“lab2”
cat >kubeadm-master.config< apiVersion: kubeadm.k8s.io/v1alpha2
kind: MasterConfiguration
kubernetesVersion: v1.11.0
imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers

apiServerCertSANs:

• “lab1”
• “lab2”
• “lab3”
• “11.11.11.111”
• “11.11.11.112”
• “11.11.11.113”
• “11.11.11.110”
• “127.0.0.1”

api:
advertiseAddress: $CP1_IP
controlPlaneEndpoint: 11.11.11.110:8443

etcd:
local:
extraArgs:
listen-client-urls: “https://127.0.0.1:2379,https://$CP{1}_{I}P:2379"advertise-client-urls:"https://$CP1_IP:2379”
listen-peer-urls: “https://$CP{1}_{I}P:2380"initial-advertise-peer-urls:"https://$CP1_IP:2380”
initial-cluster: “$CP{0}_{H}OSTNAME=https://$CP0_IP:2380,$CP{1}_{H}OSTNAME=https://$CP1_IP:2380”
initial-cluster-state: existing
serverCertSANs:
- $CP1_HOSTNAME
- $CP1_IP
peerCertSANs:
- $CP1_HOSTNAME
- $CP1_IP

controllerManagerExtraArgs:
node-monitor-grace-period: 10s
pod-eviction-timeout: 10s

networking:
podSubnet: 10.244.0.0/16

kubeProxy:
config:
# mode: ipvs
mode: iptables
EOF

配置kubelet

kubeadm alpha phase certs all --config kubeadm-master.config
kubeadm alpha phase kubelet config write-to-disk --config kubeadm-master.config
kubeadm alpha phase kubelet write-env-file --config kubeadm-master.config
kubeadm alpha phase kubeconfig kubelet --config kubeadm-master.config
systemctl restart kubelet

添加etcd到集群中

CP0_IP=“11.11.11.111”
CP0_HOSTNAME=“lab1”
CP1_IP=“11.11.11.112”
CP1_HOSTNAME=“lab2”
KUBECONFIG=/etc/kubernetes/admin.conf kubectl exec -n kube-system etcd-$CP{0}_{H}OSTNAME--etcdctl--ca-file/etc/kubernetes/pki/etcd/ca.crt--cert-file/etc/kubernetes/pki/etcd/peer.crt--key-file/etc/kubernetes/pki/etcd/peer.key--endpoints=https://${CP0_IP}:2379 member add $CP{1}_{H}OSTNAMEhttps://${CP1_IP}:2380
kubeadm alpha phase etcd local --config kubeadm-master.config

提前拉取镜像

如果执行失败 可以多次执行

kubeadm config images pull --config kubeadm-master.config

部署

kubeadm alpha phase kubeconfig all --config kubeadm-master.config
kubeadm alpha phase controlplane all --config kubeadm-master.config
kubeadm alpha phase mark-master --config kubeadm-master.config

配置第三个master节点
如下操作在lab3节点操作

1.11 版本 centos 下使用 ipvs 模式会出问题

参考 https://github.com/kubernetes/kubernetes/issues/65461

生成配置文件

CP0_IP=“11.11.11.111”
CP0_HOSTNAME=“lab1”
CP1_IP=“11.11.11.112”
CP1_HOSTNAME=“lab2”
CP2_IP=“11.11.11.113”
CP2_HOSTNAME=“lab3”
cat >kubeadm-master.config< apiVersion: kubeadm.k8s.io/v1alpha2
kind: MasterConfiguration
kubernetesVersion: v1.11.0
imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers

apiServerCertSANs:

• “lab1”
• “lab2”
• “lab3”
• “11.11.11.111”
• “11.11.11.112”
• “11.11.11.113”
• “11.11.11.110”
• “127.0.0.1”

api:
advertiseAddress: $CP2_IP
controlPlaneEndpoint: 11.11.11.110:8443

etcd:
local:
extraArgs:
listen-client-urls: “https://127.0.0.1:2379,https://$CP{2}_{I}P:2379"advertise-client-urls:"https://$CP2_IP:2379”
listen-peer-urls: “https://$CP{2}_{I}P:2380"initial-advertise-peer-urls:"https://$CP2_IP:2380”
initial-cluster: “$CP{0}_{H}OSTNAME=https://$CP0_IP:2380,$CP{1}_{H}OSTNAME=https://$CP1_IP:2380,$CP{2}_{H}OSTNAME=https://$CP2_IP:2380”
initial-cluster-state: existing
serverCertSANs:
- $CP2_HOSTNAME
- $CP2_IP
peerCertSANs:
- $CP2_HOSTNAME
- $CP2_IP

controllerManagerExtraArgs:
node-monitor-grace-period: 10s
pod-eviction-timeout: 10s

networking:
podSubnet: 10.244.0.0/16

kubeProxy:
config:
# mode: ipvs
mode: iptables
EOF

配置kubelet

kubeadm alpha phase certs all --config kubeadm-master.config
kubeadm alpha phase kubelet config write-to-disk --config kubeadm-master.config
kubeadm alpha phase kubelet write-env-file --config kubeadm-master.config
kubeadm alpha phase kubeconfig kubelet --config kubeadm-master.config
systemctl restart kubelet

添加etcd到集群中

CP0_IP=“11.11.11.111”
CP0_HOSTNAME=“lab1”
CP2_IP=“11.11.11.113”
CP2_HOSTNAME=“lab3”
KUBECONFIG=/etc/kubernetes/admin.conf kubectl exec -n kube-system etcd-$CP{0}_{H}OSTNAME--etcdctl--ca-file/etc/kubernetes/pki/etcd/ca.crt--cert-file/etc/kubernetes/pki/etcd/peer.crt--key-file/etc/kubernetes/pki/etcd/peer.key--endpoints=https://${CP0_IP}:2379 member add $CP{2}_{H}OSTNAMEhttps://${CP2_IP}:2380
kubeadm alpha phase etcd local --config kubeadm-master.config

提前拉取镜像

如果执行失败 可以多次执行

kubeadm config images pull --config kubeadm-master.config

部署

kubeadm alpha phase kubeconfig all --config kubeadm-master.config
kubeadm alpha phase controlplane all --config kubeadm-master.config
kubeadm alpha phase mark-master --config kubeadm-master.config

配置使用kubectl
如下操作在任意master节点操作
rm -rf $HOME/.kube
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id-u):$(id -g) $HOME/.kube/config

查看node节点

kubectl get nodes

只有网络插件也安装配置完成之后，才能会显示为ready状态

设置master允许部署应用pod，参与工作负载，现在可以部署其他系统组件

如 dashboard, heapster, efk等

kubectl taint nodes --all node-role.kubernetes.io/master-

配置使用网络插件
如下操作在任意master节点操作

下载配置

mkdir flannel && cd flannel
wget https://raw.githubusercontent.com/coreos/flannel/v0.10.0/Documentation/kube-flannel.yml

修改配置

此处的ip配置要与上面kubeadm的pod-network一致

net-conf.json: |
{
“Network”: “10.244.0.0/16”,
“Backend”: {
“Type”: “vxlan”
}
}

修改镜像

image: registry.cn-shanghai.aliyuncs.com/gcr-k8s/flannel:v0.10.0-amd64

如果Node有多个网卡的话，参考flannel issues 39701，

https://github.com/kubernetes/kubernetes/issues/39701

目前需要在kube-flannel.yml中使用–iface参数指定集群主机内网网卡的名称，

否则可能会出现dns无法解析。容器无法通信的情况，需要将kube-flannel.yml下载到本地，

flanneld启动参数加上–iface=

containers:
  - name: kube-flannel
    image: registry.cn-shanghai.aliyuncs.com/gcr-k8s/flannel:v0.10.0-amd64
    command:
    - /opt/bin/flanneld
    args:
    - --ip-masq
    - --kube-subnet-mgr
    - --iface=eth1

启动

kubectl apply -f kube-flannel.yml

查看

kubectl get pods --namespace kube-system
kubectl get svc --namespace kube-system

配置node节点加入集群
如下操作在所有node节点操作

此命令为初始化master成功后返回的结果

kubeadm join 11.11.11.110:8443 --token yzb7v7.dy40mhlljt1d48i9 --discovery-token-ca-cert-hash sha256:61ec309e6f942305006e6622dcadedcc64420e361231eff23cb535a183c0e77a

基础测试
测试容器间的通信和DNS
配置好网络之后，kubeadm会自动部署coredns
如下测试可以在配置kubectl的节点上操作
启动
kubectl run nginx --replicas=2 --image=nginx:alpine --port=80
kubectl expose deployment nginx --type=NodePort --name=example-service-nodeport
kubectl expose deployment nginx --name=example-service

查看状态
kubectl get deploy
kubectl get pods
kubectl get svc
kubectl describe svc example-service

DNS解析
kubectl run curl --image=radial/busyboxplus:curl -i --tty
nslookup kubernetes
nslookup example-service
curl example-service

访问测试

10.96.59.56 为查看svc时获取到的clusterip

curl “10.96.59.56:80”

32223 为查看svc时获取到的 nodeport

http://11.11.11.112:32223/
http://11.11.11.113:32223/

清理删除
kubectl delete svc example-service example-service-nodeport
kubectl delete deploy nginx curl

高可用测试
关闭任一master节点测试集群是能否正常执行上一步的基础测试，查看相关信息，不能同时关闭两个节点，因为3个节点组成的etcd集群，最多只能有一个当机。

查看组件状态

kubectl get pod --all-namespaces -o wide
kubectl get pod --all-namespaces -o wide | grep lab1
kubectl get pod --all-namespaces -o wide | grep lab2
kubectl get pod --all-namespaces -o wide | grep lab3
kubectl get nodes -o wide
kubectl get deploy
kubectl get pods
kubectl get svc

访问测试

CURL_POD=$(kubectl get pods | grep curl | grep Running | cut -d ’ ’ -f1)
kubectl exec -ti $CURL_POD – sh --tty
nslookup kubernetes
nslookup example-service
curl example-service

部署面板服务

#部署Dashboard
git clone https://github.com/bakuppus/kubernetes-dashboard.git
kubectl apply -f kubernetes-dashboard.yaml

小技巧
忘记初始master节点时的node节点加入集群命令怎么办

简单方法

kubeadm token create --print-join-command

第二种方法

token=$(kubeadm token generate)
kubeadm token create $token --print-join-command --ttl=0