二进制安装kubernetes-1.13.2

kubernetes kubernetes kubernetes

Posted by zhangshun on June 13, 2019

前言

大多数与 Kubernetes 接触频繁的人或多或少都会亲自动手使用 kubeadm ,它是管理集群生命周期的重要工具,能够帮助从创建到配置再到升级的整个流程。二进制安装kubernetes更加定制化,减去科学上网的烦恼,可以通过一步步部署的方式来学习和了解系统配置、运行原理。

软件环境

系统

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[root@master ~]# cat /etc/centos-release
CentOS Linux release 7.5.1804 (Core)

docker

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[root@master ~]# docker version
Client:
 Version:           18.06.0-ce
 API version:       1.38
 Go version:        go1.10.3
 Git commit:        0ffa825
 Built:             Wed Jul 18 19:08:18 2018
 OS/Arch:           linux/amd64
 Experimental:      false

Server:
 Engine:
  Version:          18.06.0-ce
  API version:      1.38 (minimum version 1.12)
  Go version:       go1.10.3
  Git commit:       0ffa825
  Built:            Wed Jul 18 19:10:42 2018
  OS/Arch:          linux/amd64
  Experimental:     false

kubernetes

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[root@master ~]# kubectl version
Client Version: version.Info{Major:"1", Minor:"13", GitVersion:"v1.13.2",
GitCommit:"cff46ab41ff0bb44d8584413b598ad8360ec1def", GitTreeState:"clean", BuildDate:"2019-01-10T23:35:51Z", GoVersion:"go1.11.4", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"13", GitVersion:"v1.13.2", GitCommit:"cff46ab41ff0bb44d8584413b598ad8360ec1def", GitTreeState:"clean", BuildDate:"2019-01-10T23:28:14Z", GoVersion:"go1.11.4", Compiler:"gc", Platform:"linux/amd64"}

ETCD

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[root@master ~]# etcd --version
etcd Version: 3.2.26
Git SHA: 06cec4091
Go Version: go1.8.7
Go OS/Arch: linux/amd64

Flannel

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[root@node1 zhangshun]# flanneld -version
v0.11.0

服务器规划

192.168.0.222(master):kube-apiserver,kube-controller-manager,kube-scheduler,etcd,(kubectl),kubelet,kube-proxy,docker

192.168.0.223(node1):kubelet,kube-proxy,docker,flannel,etcd

192.168.0.224(node2):kubelet,kube-proxy,docker,flannel,etcd

节点或组件功能简介

Master节点:

Master节点上面主要由四个模块组成,apiserver,schedule,controller-manager,etcd。

  • apiserver: 负责对外提供RESTful的kubernetes API 的服务,它是系统管理指令的统一接口,任何对资源的增删该查都要交给apiserver处理后再交给etcd。kubectl(kubernetes提供的客户端工具,该工具内部是对kubernetes API的调用)是直接和apiserver交互的。
  • schedule: 负责调度Pod到合适的Node上,如果把scheduler看成一个黑匣子,那么它的输入是pod和由多个Node组成的列表,输出是Pod和一个Node的绑定。kubernetes目前提供了调度算法,同样也保留了接口。用户根据自己的需求定义自己的调度算法。
  • controller-manager: 如果apiserver做的是前台的工作的话,那么controller-manager就是负责后台的。每一个资源都对应一个控制器。而control manager就是负责管理这些控制器的,比如我们通过APIServer创建了一个Pod,当这个Pod创建成功后,apiserver的任务就算完成了。
  • etcd:etcd是一个高可用的键值存储系统,kubernetes使用它来存储各个资源的状态,从而实现了Restful的API。

Node节点:

每个Node节点主要由二个模块组成:kublet, kube-proxy。

  • kube-proxy: 该模块实现了kubernetes中的服务发现和反向代理功能。kube-proxy支持TCP和UDP连接转发,默认基Round Robin算法将客户端流量转发到与service对应的一组后端pod。服务发现方面,kube-proxy使用etcd的watch机制监控集群中service和endpoint对象数据的动态变化,并且维护一个service到endpoint的映射关系,从而保证了后端pod的IP变化不会对访问者造成影响,另外,kube-proxy还支持session affinity。
  • kublet:kublet是Master在每个Node节点上面的agent,是Node节点上面最重要的模块,它负责维护和管理该Node上的所有容器,但是如果容器不是通过kubernetes创建的,它并不会管理。本质上,它负责使Pod的运行状态与期望的状态一致。

Kubernetes工作流程

流程

操作步骤


1、初始化设置(所有主机都执行)

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# Add host domain name
cat>>/etc/hosts<<EOF
192.168.0.222 master
192.168.0.223 node1
192.168.0.224 node2
EOF
# Modify related kernel parameters
cat>/etc/sysctl.d/kubernetes.conf<<EOF
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl -p /etc/sysctl.d/kubernetes.conf>&/dev/null
# Turn off and disable the firewalld
systemctl stop firewalld
systemctl disable firewalld
# Disable the SELinux
sed -i.bak 's/=enforcing/=disabled/' /etc/selinux/config
# Disable the swap
sed -i.bak 's/^.*swap/#&/g' /etc/fstab

2、安装Docker Engine并设置(所有主机都执行)

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curl http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -o /etc/yum.repos.d/docker-ce.repo>&/dev/null
yum list docker-ce --showduplicates|grep "^doc"|sort -r
yum -y install docker-ce-18.06.0.ce-3.el7
rm -f /etc/yum.repos.d/docker-ce.repo
systemctl enable docker && systemctl start docker && systemctl status docker

3、下载相关二进制包

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curl -L -C - -O https://dl.k8s.io/v1.13.2/kubernetes-server-linux-amd64.tar.gz
curl -L -C - -O https://github.com/etcd-io/etcd/releases/download/v3.2.26/etcd-v3.2.26-linux-amd64.tar.gz
curl -L -C - -O https://pkg.cfssl.org/R1.2/cfssl_linux-amd64
curl -L -C - -O https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64
curl -L -C - -O https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64
curl -L -C - -O https://github.com/coreos/flannel/releases/download/v0.11.0/flannel-v0.11.0-linux-amd64.tar.gz

4、部署etcd集群

①. 创建CA证书(master执行)

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mv cfssl* /usr/local/bin/
chmod +x /usr/local/bin/cfssl*
ETCD_SSL=/etc/etcd/ssl
mkdir -p $ETCD_SSL
cat<<EOF>$ETCD_SSL/ca-config.json
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "www": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}
EOF

cat<<EOF>$ETCD_SSL/ca-csr.json
{
    "CN": "etcd CA",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing"
        }
    ]
}
EOF

cat<<EOF>$ETCD_SSL/server-csr.json
{
    "CN": "etcd",
    "hosts": [
    "192.168.0.222",
    "192.168.0.223",
    "192.168.0.224"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing"
        }
    ]
}
EOF

cd $ETCD_SSL
cfssl_linux-amd64 gencert -initca ca-csr.json | cfssljson_linux-amd64 -bare ca -
cfssl_linux-amd64 gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=www server-csr.json | cfssljson_linux-amd64 -bare server
cd ~
# ca-key.pem  ca.pem  server-key.pem  server.pem
ls $ETCD_SSL/*.pem

②配置etcd服务

在Master节点上进行配置

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ETCD_CONF=/etc/etcd/etcd.conf
ETCD_SSL=/etc/etcd/ssl
ETCD_SERVICE=/usr/lib/systemd/system/etcd.service
cd && tar -xzf etcd-v3.3.11-linux-amd64.tar.gz
cp -p etcd-v3.3.11-linux-amd64/etc* /usr/local/bin/

# The etcd configuration file
cat>$ETCD_CONF<<EOF
#[Member]
ETCD_NAME="etcd-01"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.0.222:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.0.222:2379"

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.0.222:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.0.222:2379"
ETCD_INITIAL_CLUSTER="etcd-01=https://192.168.0.222:2380,etcd-02=https://192.168.0.223:2380,etcd-03=https://192.168.0.224:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF

# The etcd servcie configuration file
cat>$ETCD_SERVICE<<EOF
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target

[Service]
Type=notify
EnvironmentFile=$ETCD_CONF
ExecStart=/usr/local/bin/etcd \
--name=\${ETCD_NAME} \
--data-dir=\${ETCD_DATA_DIR} \
--listen-peer-urls=\${ETCD_LISTEN_PEER_URLS} \
--listen-client-urls=\${ETCD_LISTEN_CLIENT_URLS},http://127.0.0.1:2379 \
--advertise-client-urls=\${ETCD_ADVERTISE_CLIENT_URLS} \
--initial-advertise-peer-urls=\${ETCD_INITIAL_ADVERTISE_PEER_URLS} \
--initial-cluster=\${ETCD_INITIAL_CLUSTER} \
--initial-cluster-token=\${ETCD_INITIAL_CLUSTER_TOKEN} \
--initial-cluster-state=new \
--cert-file=/etc/etcd/ssl/server.pem \
--key-file=/etc/etcd/ssl/server-key.pem \
--peer-cert-file=/etc/etcd/ssl/server.pem \
--peer-key-file=/etc/etcd/ssl/server-key.pem \
--trusted-ca-file=/etc/etcd/ssl/ca.pem \
--peer-trusted-ca-file=/etc/etcd/ssl/ca.pem
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable etcd.service --now
systemctl status etcd

在Node1节点上进行配置

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ETCD_SSL=/etc/etcd/ssl
mkdir -p $ETCD_SSL
scp master:~/etcd-v3.3.11-linux-amd64.tar.gz .
scp master:$ETCD_SSL/{ca*pem,server*pem} $ETCD_SSL/
scp master:/etc/etcd/etcd.conf /etc/etcd/
scp master:/usr/lib/systemd/system/etcd.service /usr/lib/systemd/system/
tar -xvzf etcd-v3.3.11-linux-amd64.tar.gz
mv ~/etcd-v3.3.11-linux-amd64/etcd* /usr/local/bin/
sed -i '/ETCD_NAME/{s/etcd-01/etcd-02/g}' /etc/etcd/etcd.conf
sed -i '/ETCD_LISTEN_PEER_URLS/{s/0.222/0.223/g}' /etc/etcd/etcd.conf
sed -i '/ETCD_LISTEN_CLIENT_URLS/{s/0.222/0.223/g}' /etc/etcd/etcd.conf
sed -i '/ETCD_INITIAL_ADVERTISE_PEER_URLS/{s/0.222/0.223/g}' /etc/etcd/etcd.conf
sed -i '/ETCD_ADVERTISE_CLIENT_URLS/{s/0.222/0.223/g}' /etc/etcd/etcd.conf
rm -rf ~/etcd-v3.3.11-linux-amd64*
systemctl daemon-reload
systemctl enable etcd.service --now
systemctl status etcd

在Node2节点上进行配置

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ETCD_SSL=/etc/etcd/ssl
mkdir -p $ETCD_SSL
scp master:~/etcd-v3.3.11-linux-amd64.tar.gz .
scp master:$ETCD_SSL/{ca*pem,server*pem} $ETCD_SSL/
scp master:/etc/etcd/etcd.conf /etc/etcd/
scp master:/usr/lib/systemd/system/etcd.service /usr/lib/systemd/system/
tar -xvzf etcd-v3.3.11-linux-amd64.tar.gz
mv ~/etcd-v3.3.11-linux-amd64/etcd* /usr/local/bin/
sed -i '/ETCD_NAME/{s/etcd-01/etcd-03/g}' /etc/etcd/etcd.conf
sed -i '/ETCD_LISTEN_PEER_URLS/{s/0.222/0.224/g}' /etc/etcd/etcd.conf
sed -i '/ETCD_LISTEN_CLIENT_URLS/{s/0.222/0.224/g}' /etc/etcd/etcd.conf
sed -i '/ETCD_INITIAL_ADVERTISE_PEER_URLS/{s/0.222/0.224/g}' /etc/etcd/etcd.conf
sed -i '/ETCD_ADVERTISE_CLIENT_URLS/{s/0.222/0.224/g}' /etc/etcd/etcd.conf
rm -rf ~/etcd-v3.3.11-linux-amd64*
systemctl daemon-reload
systemctl enable etcd.service --now
systemctl status etcd

主要参数:

  • ETCD_NAME:节点名称。
  • ETCD_DATA_DIR:数据目录。
  • ETCD_LISTEN_PEER_URLS:集群通信监听地址。
  • ETCD_LISTEN_CLIENT_URLS:客户端访问监听地址。
  • ETCD_INITIAL_ADVERTISE_PEER_URLS:集群通告地址。
  • ETCD_ADVERTISE_CLIENT_URLS:客户端通告地址。
  • ETCD_INITIAL_CLUSTER:集群节点地址。
  • ETCD_INITIAL_CLUSTER_TOKEN:集群Token。
  • ETCD_INITIAL_CLUSTER_STATE:加入集群的当前状态,new是新集群,existing表示加入已有集群。

注意:etcd启动时需要一起同时启动

③验证etcd集群是否部署成功

执行以下命令:

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etcdctl \
--ca-file=/etc/etcd/ssl/ca.pem \
--cert-file=/etc/etcd/ssl/server.pem \
--key-file=/etc/etcd/ssl/server-key.pem \
--endpoints="https://192.168.0.222:2379,https://192.168.0.223:2379,https://192.168.0.224:2379" cluster-health

5、部署Flannel网络(node上执行)

由于Flannel需要使用etcd存储自身的一个子网信息,所以要保证能成功连接Etcd,写入预定义子网段。写入的Pod网段${CLUSTER_CIDR}必须是/16段地址,必须与kube-controller-manager的–-cluster-cidr参数值一致。一般情况下,在每一个Node节点都需要进行配置

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KUBE_CONF=/etc/kubernetes
FLANNEL_CONF=$KUBE_CONF/flannel.conf
mkdir $KUBE_CONF
tar -xvzf flannel-v0.11.0-linux-amd64.tar.gz
mv {flanneld,mk-docker-opts.sh} /usr/local/bin/
# Check whether etcd cluster is healthy.
etcdctl \
--ca-file=/etc/etcd/ssl/ca.pem \
--cert-file=/etc/etcd/ssl/server.pem \
--key-file=/etc/etcd/ssl/server-key.pem \
--endpoints="https://192.168.0.222:2379,\
https://192.168.0.223:2379,\
https://192.168.0.224:2379" cluster-health
# Writing into a predetermined subnetwork.
cd /etc/etcd/ssl
etcdctl \
--ca-file=ca.pem --cert-file=server.pem --key-file=server-key.pem \
--endpoints="https://192.168.0.222:2379,https://192.168.0.223:2379,https://192.168.0.224:2379" \
set /coreos.com/network/config  '{ "Network": "172.17.0.0/16", "Backend": {"Type": "vxlan"}}'
cd ~
# Configuration the flannel service.
cat>$FLANNEL_CONF<<EOF
FLANNEL_OPTIONS="--etcd-endpoints=https://192.168.0.222:2379,https://192.168.0.223:2379,https://192.168.0.224:2379 -etcd-cafile=/etc/etcd/ssl/ca.pem -etcd-certfile=/etc/etcd/ssl/server.pem -etcd-keyfile=/etc/etcd/ssl/server-key.pem"
EOF

cat>/usr/lib/systemd/system/flanneld.service<<EOF
[Unit]
Description=Flanneld overlay address etcd agent
After=network-online.target network.target
Before=docker.service

[Service]
Type=notify
EnvironmentFile=$FLANNEL_CONF
ExecStart=/usr/local/bin/flanneld --ip-masq \$FLANNEL_OPTIONS
ExecStartPost=/usr/local/bin/mk-docker-opts.sh -k DOCKER_NETWORK_OPTIONS -d /run/flannel/subnet.env
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

# Modify the docker service.
sed -i.bak -e '/ExecStart/i EnvironmentFile=\/run\/flannel\/subnet.env' -e 's/ExecStart=\/usr\/bin\/dockerd/ExecStart=\/usr\/bin\/dockerd $DOCKER_NETWORK_OPTIONS/g' /usr/lib/systemd/system/docker.service
# Start or restart related services.
systemctl daemon-reload
systemctl enable flanneld --now
systemctl restart docker
systemctl status flanneld
systemctl status docker
ip address show

6、部署Master节点

①创建CA证书

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KUBE_SSL=/etc/kubernetes/ssl
mkdir $KUBE_SSL

# Create CA.
cat>$KUBE_SSL/ca-config.json<<EOF
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "kubernetes": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}
EOF
cat>$KUBE_SSL/ca-csr.json<<EOF
{
    "CN": "kubernetes",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}
EOF
cat>$KUBE_SSL/server-csr.json<<EOF
{
    "CN": "kubernetes",
    "hosts": [
      "10.0.0.1",
      "127.0.0.1",
      "192.168.0.222",
      "kubernetes",
      "kubernetes.default",
      "kubernetes.default.svc",
      "kubernetes.default.svc.cluster",
      "kubernetes.default.svc.cluster.local"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}
EOF
cd $KUBE_SSL
cfssl_linux-amd64 gencert -initca ca-csr.json | cfssljson_linux-amd64 -bare ca -
cfssl_linux-amd64 gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes server-csr.json | cfssljson_linux-amd64 -bare server
# Create kube-proxy CA.
cat>$KUBE_SSL/kube-proxy-csr.json<<EOF
{
  "CN": "system:kube-proxy",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing",
      "ST": "BeiJing",
      "O": "k8s",
      "OU": "System"
    }
  ]
}
EOF
cfssl_linux-amd64 gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-proxy-csr.json | cfssljson_linux-amd64 -bare kube-proxy
cd ~

②安装配置kube-apiserver服务

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KUBE_ETC=/etc/kubernetes
KUBE_API_CONF=/etc/kubernetes/apiserver.conf
tar -xvzf kubernetes-server-linux-amd64.tar.gz
mv kubernetes/server/bin/{kube-apiserver,kube-scheduler,kube-controller-manager} /usr/local/bin/
# Create a token file.
cat>$KUBE_ETC/token.csv<<EOF
$(head -c 16 /dev/urandom | od -An -t x | tr -d ' '),kubelet-bootstrap,10001,"system:kubelet-bootstrap"
EOF
# Create a kube-apiserver configuration file.
cat >$KUBE_API_CONF<<EOF
KUBE_APISERVER_OPTS="--logtostderr=true \
--v=4 \
--etcd-servers=https://192.168.0.222:2379,https://192.168.0.223:2379,https://192.168.0.224:2379 \
--bind-address=192.168.0.222 \
--secure-port=6443 \
--advertise-address=192.168.0.222 \
--allow-privileged=true \
--service-cluster-ip-range=10.0.0.0/24 \
--enable-admission-plugins=NamespaceLifecycle,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota,NodeRestriction \
--authorization-mode=RBAC,Node \
--enable-bootstrap-token-auth \
--token-auth-file=$KUBE_ETC/token.csv \
--service-node-port-range=30000-50000 \
--tls-cert-file=$KUBE_ETC/ssl/server.pem  \
--tls-private-key-file=$KUBE_ETC/ssl/server-key.pem \
--client-ca-file=$KUBE_ETC/ssl/ca.pem \
--service-account-key-file=$KUBE_ETC/ssl/ca-key.pem \
--etcd-cafile=/etc/etcd/ssl/ca.pem \
--etcd-certfile=/etc/etcd/ssl/server.pem \
--etcd-keyfile=/etc/etcd/ssl/server-key.pem"
EOF

# Create the kube-apiserver service.
cat>/usr/lib/systemd/system/kube-apiserver.service<<EOF
[Unit]
Description=Kubernetes API Server
Documentation=https://github.com/kubernetes/kubernetes
After=etcd.service
Wants=etcd.service

[Service]
EnvironmentFile=-$KUBE_API_CONF
ExecStart=/usr/local/bin/kube-apiserver \$KUBE_APISERVER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kube-apiserver.service --now
systemctl status kube-apiserver.service

参数说明:

  • --logtostderr:启用日志。
  • --v:日志等级。
  • --etcd-servers:etcd集群地址。
  • --bind-address:监听地址。
  • --secure-port:https安全端口。
  • --advertise-address:集群通告地址。
  • --allow-privileged:启用授权。
  • --service-cluster-ip-range:Service虚拟IP地址段。
  • --enable-admission-plugins:准入控制模块。
  • --authorization-mode:认证授权,启用RBAC授权和节点自管理。
  • --enable-bootstrap-token-auth:启用TLS bootstrap功能。
  • --token-auth-file:token文件。
  • --service-node-port-range:Service Node类型默认分配端口范围。

③安装配置kube-scheduler服务

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KUBE_ETC=/etc/kubernetes
KUBE_SCHEDULER_CONF=$KUBE_ETC/kube-scheduler.conf
cat>$KUBE_SCHEDULER_CONF<<EOF
KUBE_SCHEDULER_OPTS="--logtostderr=true \
--v=4 \
--master=127.0.0.1:8080 \
--leader-elect"
EOF

cat>/usr/lib/systemd/system/kube-scheduler.service<<EOF
[Unit]
Description=Kubernetes Scheduler
Documentation=https://github.com/kubernetes/kubernetes

[Service]
EnvironmentFile=-$KUBE_SCHEDULER_CONF
ExecStart=/usr/local/bin/kube-scheduler \$KUBE_SCHEDULER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kube-scheduler.service --now
systemctl status kube-scheduler.service

参数说明:

  • --master:连接本地apiserver。
  • --leader-elect:当该组件启动多个时,自动选举(HA),被选为 leader的节点负责处理工作,其它节点为阻塞状态。

④安装配置kube-controller服务

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KUBE_CONTROLLER_CONF=/etc/kubernetes/kube-controller-manager.conf
cat>$KUBE_CONTROLLER_CONF<<EOF
KUBE_CONTROLLER_MANAGER_OPTS="--logtostderr=true \
--v=4 \
--master=127.0.0.1:8080 \
--leader-elect=true \
--address=127.0.0.1 \
--service-cluster-ip-range=10.0.0.0/24 \
--cluster-name=kubernetes \
--cluster-signing-cert-file=/etc/kubernetes/ssl/ca.pem \
--cluster-signing-key-file=/etc/kubernetes/ssl/ca-key.pem  \
--root-ca-file=/etc/kubernetes/ssl/ca.pem \
--service-account-private-key-file=/etc/kubernetes/ssl/ca-key.pem"
EOF
cat>/usr/lib/systemd/system/kube-controller-manager.service<<EOF
[Unit]
Description=Kubernetes Controller Manager
Documentation=https://github.com/kubernetes/kubernetes

[Service]
EnvironmentFile=-$KUBE_CONTROLLER_CONF
ExecStart=/usr/local/bin/kube-controller-manager \$KUBE_CONTROLLER_MANAGER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kube-controller-manager.service --now
systemctl status kube-controller-manager.service

⑤查看集群状态

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mv kubernetes/server/bin/kubectl /usr/local/bin/
[root@master ~]# kubectl get cs
NAME                 STATUS    MESSAGE              ERROR
controller-manager   Healthy   ok                   
scheduler            Healthy   ok                   
etcd-0               Healthy   {"health": "true"}   
etcd-2               Healthy   {"health": "true"}   
etcd-1               Healthy   {"health": "true"}

7、部署Node节点

①创建bootstrap和kube-proxy的kubeconfig文件(master上执行)

Master apiserver启用TLS认证后,Node节点kubelet组件想要加入集群,必须使用CA签发的有效证书才能与apiserver通信,当Node节点很多时,签署证书是一件很繁琐的事情,因此有了TLS Bootstrapping机制,kubelet会以一个低权限用户自动向apiserver申请证书,kubelet的证书由apiserver动态签署。在前面创建的token文件在这一步派上了用场

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BOOTSTRAP_TOKEN=$(awk -F "," '{print $1}' /etc/kubernetes/token.csv)
KUBE_SSL=/etc/kubernetes/ssl/
KUBE_APISERVER="https://192.168.0.222:6443"
cd $KUBE_SSL
# Set cluster parameters.
kubectl config set-cluster kubernetes \
  --certificate-authority=./ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=bootstrap.kubeconfig
# Set client parameters.
kubectl config set-credentials kubelet-bootstrap \
  --token=${BOOTSTRAP_TOKEN} \
  --kubeconfig=bootstrap.kubeconfig
# Set context parameters. 
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kubelet-bootstrap \
  --kubeconfig=bootstrap.kubeconfig
# Set context.
kubectl config use-context default --kubeconfig=bootstrap.kubeconfig
# Create kube-proxy kubeconfig file. 
kubectl config set-cluster kubernetes \
  --certificate-authority=./ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=kube-proxy.kubeconfig
kubectl config set-credentials kube-proxy \
  --client-certificate=./kube-proxy.pem \
  --client-key=./kube-proxy-key.pem \
  --embed-certs=true \
  --kubeconfig=kube-proxy.kubeconfig
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-proxy \
  --kubeconfig=kube-proxy.kubeconfig
kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig
cd ~

# Bind kubelet-bootstrap user to system cluster roles.
kubectl create clusterrolebinding kubelet-bootstrap \
  --clusterrole=system:node-bootstrapper \
  --user=kubelet-bootstrap

②配置kube-proxy和kubelet服务(node上执行)

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KUBE_CONF=/etc/kubernetes
KUBE_SSL=$KUBE_CONF/ssl
IP=192.168.0.223
mkdir $KUBE_SSL
scp master:~/kubernetes/server/bin/{kube-proxy,kubelet} /usr/local/bin/
scp master:$KUBE_CONF/ssl/{bootstrap.kubeconfig,kube-proxy.kubeconfig} $KUBE_CONF
cat>$KUBE_CONF/kube-proxy.conf<<EOF
KUBE_PROXY_OPTS="--logtostderr=true \
--v=4 \
--hostname-override=$IP \
--cluster-cidr=10.0.0.0/24 \
--kubeconfig=$KUBE_CONF/kube-proxy.kubeconfig"
EOF

cat>/usr/lib/systemd/system/kube-proxy.service<<EOF
[Unit]
Description=Kubernetes Proxy
After=network.target

[Service]
EnvironmentFile=-$KUBE_CONF/kube-proxy.conf
ExecStart=/usr/local/bin/kube-proxy \$KUBE_PROXY_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kube-proxy.service --now
systemctl status kube-proxy.service -l
cat>$KUBE_CONF/kubelet.yaml<<EOF
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: $IP
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS: ["10.0.0.2"]
clusterDomain: cluster.local.
failSwapOn: false
authentication:
  anonymous:
    enabled: true
EOF
cat>$KUBE_CONF/kubelet.conf<<EOF
KUBELET_OPTS="--logtostderr=true \
--v=4 \
--hostname-override=$IP \
--kubeconfig=$KUBE_CONF/kubelet.kubeconfig \
--bootstrap-kubeconfig=$KUBE_CONF/bootstrap.kubeconfig \
--config=$KUBE_CONF/kubelet.yaml \
--cert-dir=$KUBE_SSL \
--pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0"
EOF
cat>/usr/lib/systemd/system/kubelet.service<<EOF
[Unit]
Description=Kubernetes Kubelet
After=docker.service
Requires=docker.service

[Service]
EnvironmentFile=$KUBE_CONF/kubelet.conf
ExecStart=/usr/local/bin/kubelet \$KUBELET_OPTS
Restart=on-failure
KillMode=process

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kubelet.service --now
systemctl status kubelet.service -l

参数说明:

  • --hostname-override:在集群中显示的主机名。
  • --kubeconfig:指定kubeconfig文件位置,会自动生成。
  • --bootstrap-kubeconfig:指定刚才生成的bootstrap.kubeconfig文件。
  • --cert-dir:颁发证书存放位置。
  • --pod-infra-container-image:管理Pod网络的镜像。

③Approve kubelet CSR请求(master上执行)

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[root@master ~]# kubectl get csr
NAME                                                   AGE   REQUESTOR           CONDITION
node-csr-FpTP2sCI0SiYDCxaIHa1SRukS_5u9BQN10BsTd6RU1Y   20m   kubelet-bootstrap   Pending
node-csr-YYfnPwAws2LxJzV-OgYjJ22zy_z9XQM8PT0MnqZN910   24m   kubelet-bootstrap   Pending

kubectl certificate approve node-csr-FpTP2sCI0SiYDCxaIHa1SRukS_5u9BQN10BsTd6RU1Y
kubectl certificate approve node-csr-YYfnPwAws2LxJzV-OgYjJ22zy_z9XQM8PT0MnqZN910

④查看集群状态

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[root@master ~]# kubectl get cs
NAME                 STATUS    MESSAGE              ERROR
scheduler            Healthy   ok                   
controller-manager   Healthy   ok                   
etcd-1               Healthy   {"health": "true"}   
etcd-0               Healthy   {"health": "true"}   
etcd-2               Healthy   {"health": "true"}

[root@master ~]# kubectl get node
NAME            STATUS   ROLES    AGE   VERSION
192.168.0.223   Ready    <none>   20h   v1.13.2
192.168.0.224   Ready    <none>   20h   v1.13.2

8、运行一个测试

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[root@master ~]#  kubectl run nginx --image=nginx --replicas=3
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
deployment.apps/nginx created
[root@master ~]# kubectl expose deployment nginx --port=88 --target-port=80 --type=NodePort
service/nginx exposed
[root@gysl-master ~]# kubectl get pods
NAME                     READY   STATUS              RESTARTS   AGE
nginx-7cdbd8cdc9-7h946   0/1     ContainerCreating   0          33s
nginx-7cdbd8cdc9-vtkqf   0/1     ContainerCreating   0          33s
nginx-7cdbd8cdc9-wdjtj   0/1     ContainerCreating   0          33s
[root@master ~]# kubectl get svc
NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)        AGE
kubernetes   ClusterIP   10.0.0.1     <none>        443/TCP        8h
nginx        NodePort    10.0.0.2     <none>        88:46705/TCP   28s
[root@master ~]# kubectl get pods
NAME                     READY   STATUS    RESTARTS   AGE
nginx-7cdbd8cdc9-7h946   1/1     Running   0          2m4s
nginx-7cdbd8cdc9-vtkqf   1/1     Running   0          2m4s
nginx-7cdbd8cdc9-wdjtj   1/1     Running   0          2m4s
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[root@node1 ~]# curl http://10.0.0.2:88
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
    body {
        width: 35em;
        margin: 0 auto;
        font-family: Tahoma, Verdana, Arial, sans-serif;
    }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>

<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>

<p><em>Thank you for using nginx.</em></p>
</body>
</html>

9、在Master节点部署Node节点的相关组件

资源比较充裕的情况下,Master节点仅仅做为服务接口、调度、控制节点,必须部署的组件有:kube-apiserver、kube-controller-manager、kube-scheduler、kubectl、etcd。除此之外,一般还需要做HA等相关部署。如果Master节点资源比较充裕,有些实验也要求至少有三个节点在运行,那么也可以将Master节点部署设置为一般Node节点来使用。

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KUBE_CONF=/etc/kubernetes
KUBE_SSL=$KUBE_CONF/ssl
IP=192.168.0.222
mkdir $KUBE_SSL
cp ~/kubernetes/server/bin/{kube-proxy,kubelet} /usr/local/bin/
cp $KUBE_CONF/ssl/{bootstrap.kubeconfig,kube-proxy.kubeconfig} $KUBE_CONF
cat>$KUBE_CONF/kube-proxy.conf<<EOF
KUBE_PROXY_OPTS="--logtostderr=true \
--v=4 \
--hostname-override=$IP \
--cluster-cidr=10.0.0.0/24 \
--kubeconfig=$KUBE_CONF/kube-proxy.kubeconfig"
EOF
cat>/usr/lib/systemd/system/kube-proxy.service<<EOF
[Unit]
Description=Kubernetes Proxy
After=network.target

[Service]
EnvironmentFile=-$KUBE_CONF/kube-proxy.conf
ExecStart=/usr/local/bin/kube-proxy \$KUBE_PROXY_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kube-proxy.service --now
systemctl status kube-proxy.service -l
cat>$KUBE_CONF/kubelet.yaml<<EOF
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: $IP
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS: ["10.0.0.2"]
clusterDomain: cluster.local.
failSwapOn: false
authentication:
  anonymous:
    enabled: true
EOF

cat>$KUBE_CONF/kubelet.conf<<EOF
KUBELET_OPTS="--logtostderr=true \
--v=4 \
--hostname-override=$IP \
--kubeconfig=$KUBE_CONF/kubelet.kubeconfig \
--bootstrap-kubeconfig=$KUBE_CONF/bootstrap.kubeconfig \
--config=$KUBE_CONF/kubelet.yaml \
--cert-dir=$KUBE_SSL \
--pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0"
EOF

cat>/usr/lib/systemd/system/kubelet.service<<EOF
[Unit]
Description=Kubernetes Kubelet
After=docker.service
Requires=docker.service

[Service]
EnvironmentFile=$KUBE_CONF/kubelet.conf
ExecStart=/usr/local/bin/kubelet \$KUBELET_OPTS
Restart=on-failure
KillMode=process

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable kubelet.service --now
systemctl status kubelet.service -l
kubectl certificate approve $(kubectl get csr | awk '{if(NR>1) print $1}')
kubectl label node 192.168.0.222  node-role.kubernetes.io/master='master'
kubectl label node 192.168.0.223  node-role.kubernetes.io/node='node'
kubectl label node 192.168.0.224  node-role.kubernetes.io/node='node'
[root@master ~]# kubectl get nodes
NAME            STATUS   ROLES    AGE   VERSION
192.168.0.222   Ready    master   22m   v1.13.2
192.168.0.223   Ready    node     11h   v1.13.2
192.168.0.224   Ready    node     11h   v1.13.2