kubenetes_V1.14.0 安装部署

k8s的安装有多种方式，如yum安装，kubeadm安装，kubemini安装，二进制安装（生产环境多采用此方式精确控制安装）等。本文是入门系列验证，之前进行过yum安装，可以查看文章《k8s入门系列之集群yum安装篇》   。这里进行kubeadm安装一次了解安装过程，真正的学习、测试环境和生产环境都不建议此方法，都建议yum安装或者二进制安装，这样才可以详细了解到k8s的工作原理和工作过程

平台 :CentOS Linux release 7.6.1810 (Core) 

master: 192.168.122.220
node1:  192.168.122.221
node2:  192.168.122.222

一，三台机器前期工作准备
1，关闭防火墙服务，避免与docker容器的防火墙规则冲突。
systemctl stop firewalld
systemctl disable firewalld

2，关闭selinux：
修改/etc/selinux/config为SELINUX=disabled
重启后配置生效。不建议临时关闭（setenfore 0），防止机器重启失效。

3，关闭swap：
临时关闭：

1. swapoff -a

永久关闭：

1. sed -i 's/.*swap.*/#&/' /etc/fstab

4，host定向,将机器内部主机名通信打通：
vi /etc/hosts

192.168.122.220 master
192.168.122.221 node01
192.168.122.222 node02

5，master机器设置免密钥登陆其他两个node

1. ssh-keygen #生成密钥对
2. cd /root/.ssh/
3. ssh-copy-id -i id_rsa.pub node01
4. ssh-copy-id -i id_rsa.pub node02

6，配置ntp：

1. yum install ntpdate -y
2. systemctl enable ntpdate.service
3. systemctl start ntpdate.service
4. 临时同步：ntpdate time7.aliyun.com
5. 设置任务计划crontab -e：
6. */30 * * * * /usr/sbin/ntpdate time7.aliyun.com >/dev/null 2>&1

7，设置内核，建议安装标准系统初始化进行（部分厂商的机器已经进行了默认参数优化）

1. echo "* soft nofile 65536">> /etc/security/limits.conf
2. echo "* hard nofile 65536" >> /etc/security/limits.conf
3. echo "* soft nproc 65536" >> /etc/security/limits.conf
4. echo "* hard nproc 65536" >> /etc/security/limits.conf
5. echo "* soft memlock unlimited" >> /etc/security/limits.conf
6. echo "* hard memlock unlimited" >> /etc/security/limits.conf

修正转发：

1. modprobe br_netfilter
2. cat < < EOF > /etc/sysctl.d/k8s.conf
3. net.bridge.bridge-nf-call-ip6tables = 1
4. net.bridge.bridge-nf-call-iptables = 1
5. EOF
6. sysctl -p /etc/sysctl.d/k8s.conf

8，设置yum源

1. epel源：
2. yum install -y epel-release
3.  
4. #kubenetes yum源 ，采用阿里云
5. cat &lt; /etc/yum.repos.d/kubernetes.repo
6. [kubernetes]
7. name=Kubernetes
8. baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
9. enabled=1
10. gpgcheck=0
11. repo_gpgcheck=0
12. gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
13. EOF
14. ---------------------
15. #docker yum源 采用阿里云
16. wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
17. yum clean all &amp;&amp; yum makecache fast

9，安装依赖包

1. yum install -y yum-utils device-mapper-persistent-data lvm2 net-tools conntrack-tools wget vim ntpdate libseccomp libtool-ltdl

二，进行kubeadm 集群安装部署
1,组件安装
master节点安装etcd：

1. yum install etcd -y
2. systemctl enable etcd

由于采用外部 etcd，所以要在 master 节点安装 etcd服务，这里也是etcd是单节点。不管是etcd集群还是单机，或者是 http, https都可以，只要在 kubeadm 中配置好就行。

master和其他node：

1. yum install docker-ce kubelet kubeadm kubectl ipvsadm -y
2. systemctl restart kubelet
3. systemctl restart docker
4. systemctl enable kubelet
5. systemctl enable docker

2,kubeadm安装配置 kubenetes 1.12.2集群

1. kubeadm init --kubernetes-version=v1.12.2 --pod-network-cidr=10.244.0.0/16 --apiserver-advertise-address=10.1.14.12

这里由于我的虚拟机都设置了科学上网，所以可以直接去下载。 没有配置科学上网的，建议采用阿里云的镜像下载后更改tag处理再kubeadm安装。
安装完信息如下，则说明初始化成功：

[root@master docker]# kubeadm init  --kubernetes-version=v1.12.2 --pod-network-cidr=10.244.0.0/16  --apiserver-advertise-address=10.1.14.12
[init] using Kubernetes version: v1.12.2
[preflight] running pre-flight checks
        [WARNING Service-Docker]: docker service is not enabled, please run 'systemctl enable docker.service'
[preflight/images] Pulling images required for setting up a Kubernetes cluster
[preflight/images] This might take a minute or two, depending on the speed of your internet connection
[preflight/images] You can also perform this action in beforehand using 'kubeadm config images pull'
[kubelet] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[preflight] Activating the kubelet service
[certificates] Generated front-proxy-ca certificate and key.
[certificates] Generated front-proxy-client certificate and key.
[certificates] Generated ca certificate and key.
[certificates] Generated apiserver certificate and key.
[certificates] apiserver serving cert is signed for DNS names [master kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 10.1.14.12]
[certificates] Generated apiserver-kubelet-client certificate and key.
[certificates] Generated etcd/ca certificate and key.
[certificates] Generated etcd/peer certificate and key.
[certificates] etcd/peer serving cert is signed for DNS names [master localhost] and IPs [10.1.14.12 127.0.0.1 ::1]
[certificates] Generated etcd/healthcheck-client certificate and key.
[certificates] Generated apiserver-etcd-client certificate and key.
[certificates] Generated etcd/server certificate and key.
[certificates] etcd/server serving cert is signed for DNS names [master localhost] and IPs [127.0.0.1 ::1]
[certificates] valid certificates and keys now exist in "/etc/kubernetes/pki"
[certificates] Generated sa key and public key.
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/admin.conf"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/kubelet.conf"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/controller-manager.conf"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/scheduler.conf"
[controlplane] wrote Static Pod manifest for component kube-apiserver to "/etc/kubernetes/manifests/kube-apiserver.yaml"
[controlplane] wrote Static Pod manifest for component kube-controller-manager to "/etc/kubernetes/manifests/kube-controller-manager.yaml"
[controlplane] wrote Static Pod manifest for component kube-scheduler to "/etc/kubernetes/manifests/kube-scheduler.yaml"
[etcd] Wrote Static Pod manifest for a local etcd instance to "/etc/kubernetes/manifests/etcd.yaml"
[init] waiting for the kubelet to boot up the control plane as Static Pods from directory "/etc/kubernetes/manifests" 
[init] this might take a minute or longer if the control plane images have to be pulled
[apiclient] All control plane components are healthy after 39.007740 seconds
[uploadconfig] storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.12" in namespace kube-system with the configuration for the kubelets in the cluster
[markmaster] Marking the node master as master by adding the label "node-role.kubernetes.io/master=''"
[markmaster] Marking the node master as master by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[patchnode] Uploading the CRI Socket information "/var/run/dockershim.sock" to the Node API object "master" as an annotation
[bootstraptoken] using token: wzh9es.gaz6xloz7omrswvs
[bootstraptoken] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstraptoken] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstraptoken] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstraptoken] creating the "cluster-info" ConfigMap in the "kube-public" namespace
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy
 
Your Kubernetes master 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
 
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 machines by running the following on each node
as root:
 
kubeadm join 192.168.122.220:6443 --token ry7iaa.ysxah86uu9erif9v 
    --discovery-token-ca-cert-hash sha256:9b7b17fd3da2e16925a3a729a362d04b19c0a3d73a2f2f1b13d44134db3166af

里边的信息量很大，可以多仔细看两遍,其中最后将node加入集群的命令可以记录一下。

按照提示，在开始使用集群之前，执行如下命令（提示信息直接贴过来即可）：

1. mkdir -p $HOME/.kube
2. sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
3. sudo chown $(id -u):$(id -g) $HOME/.kube/config

配置完毕以后查看node信息：

1. [root@master ~]# kubectl get node
2. NAME STATUS ROLES AGE VERSION
3. master NotReady master 8m5s v1.12.2

原因是flannel没有配置，配置flannel：

1. kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
2. kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/k8s-manifests/kube-flannel-rbac.yml

重新查看：

1. [root@master ~]# kubectl get node
2. NAME STATUS ROLES AGE VERSION
3. master Ready master 16m v1.12.2
4. [root@master ~]# kubectl get pods --all-namespaces
5. NAMESPACE NAME READY STATUS RESTARTS AGE
6. kube-system coredns-576cbf47c7-ftvc8 1/1 Running 0 15m
7. kube-system coredns-576cbf47c7-rtm6f 1/1 Running 0 15m
8. kube-system etcd-master 1/1 Running 0 75s
9. kube-system kube-apiserver-master 1/1 Running 0 66s
10. kube-system kube-controller-manager-master 1/1 Running 0 77s
11. kube-system kube-flannel-ds-amd64-488hv 1/1 Running 0 99s
12. kube-system kube-proxy-d4v7j 1/1 Running 0 15m
13. kube-system kube-scheduler-master 1/1 Running 0 77s
14. [root@master ~]# kubectl get cs
15. NAME STATUS MESSAGE ERROR
16. scheduler Healthy ok
17. controller-manager Healthy ok
18. etcd-0 Healthy {"health": "true"}

3,node节点配置
node01和node02分别执行之前的命令提示，将node01 node02加入到集群：

systemctl stop firewalld
systemctl disable firewalld
setenforce 0
swapoff -a
sed -i 's/.*swap.*/#&/' /etc/fstab

yum install ntpdate -y
systemctl enable ntpdate.service
systemctl start ntpdate.service

echo "* soft nofile 65536">> /etc/security/limits.conf
echo "* hard nofile 65536" >> /etc/security/limits.conf
echo "* soft nproc 65536" >> /etc/security/limits.conf
echo "* hard nproc 65536" >> /etc/security/limits.conf
echo "* soft memlock unlimited" >> /etc/security/limits.conf
echo "* hard memlock unlimited" >> /etc/security/limits.conf

cat << EOF > /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl -p /etc/sysctl.d/k8s.conf
yum install docker-ce kubelet kubeadm kubectl ipvsadm -y
yum install -y epel-release

cd /etc/yum.repos.d/

wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

yum install -y yum-utils device-mapper-persistent-data lvm2 net-tools conntrack-tools wget vim ntpdate libseccomp libtool-ltdl
yum install etcd -y
systemctl enable etcd
yum install docker-ce kubelet kubeadm kubectl ipvsadm -y
systemctl restart kubelet
systemctl restart docker
systemctl enable kubelet
systemctl enable docker

kubeadm join 192.168.122.220:6443 --token ry7iaa.ysxah86uu9erif9v     --discovery-token-ca-cert-hash sha256:9b7b17fd3da2e16925a3a729a362d04b19c0a3d73a2f2f1b13d44134db3166af