IT苦工指南 | Kubernetes v1.8.x全手動安裝

時間 2020-01-23

標籤苦工指南 kubernetes v1.8.x 手動安裝简体版

原文原文鏈接

最近，有部分用戶飄了……node

以爲Rainbond提供的既簡潔、又易用、並且生產就緒的Kubernets體驗不過癮……linux

想要挑戰一下Kubernetes全手動部署……nginx

並在凌晨一點撥通了客服小哥的電話……git

所以本着不重複造輪子而且關愛客服小哥身心健康的主張，咱們搬來了Kairen的精彩教程——github

開始

Kubernetes官方提供了多種安裝方式Picking the right solution，本文將以全手動安裝方式來部署Kubernetes v1.8.x版本，學習和了解Kubernetes的構建流程。web

版本明細：docker

Kubernetes v1.8.6
CNI v0.6.0
Etcd v3.2.9
Calico v2.6.2
Docker v17.10.0-ce

準備

系統：ubuntu 16.x 或 centos 7.x
節點：json

172.16.35.12 / master1 / 1 CPU / 2G
172.16.35.10 / node1 / 1 CPU / 2G
172.16.35.11 / node2 / 1 CPU / 2G

master爲主要控制節點和部署節點，node爲應用運行節點
全部操做均爲 root

安裝前需確認如下事項：bootstrap

確認全部節點之間網絡互通，master1 SSH登入其餘節點爲passwordless
確認防火牆和SELinux已關閉，如centos:

$ systemctl stop firewalld && systemctl disable firewalld
$ setenforce 0
$ vim /etc/selinux/config
SELINUX=disabled

全部節點須要設置/etc/host解析到全部主機

...
172.16.35.10 node1
172.16.35.11 node2
172.16.35.12 master1

全部節點都須要安裝dockerubuntu

$ curl -fsSL "https://get.docker.com/" | sh

注意：centos安裝docker完成後須要執行：
$ systemctl enable docker && systemctl start docker

編輯/lib/systemd/system/docker.service，在ExecStart=..加入：

ExecStartPost=/sbin/iptables -A FORWARD -s 0.0.0.0/0 -j ACCEPT

完成後重啓docker服務：
$ systemctl daemon-reload && systemctl restart docker

全部節點都須要設定/etc/sysctl.d/k8s.conf系統參數

$ cat <<EOF > /etc/sysctl.d/k8s.conf
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/k8s.conf

在master1安裝CFSSL工具，用來創建TLS certificates

$ export CFSSL_URL="https://pkg.cfssl.org/R1.2"
$ wget "${CFSSL_URL}/cfssl_linux-amd64" -O /usr/local/bin/cfssl
$ wget "${CFSSL_URL}/cfssljson_linux-amd64" -O /usr/local/bin/cfssljson
$ chmod +x /usr/local/bin/cfssl /usr/local/bin/cfssljson

Etcd

安裝Kubernetes以前，咱們須要完成一些必要的系統配置，高可用共享配置和服務發現存儲Etcd即是其中的重要一環，節點會從Etcd中獲取所需數據。

創建集羣CA和certificates

這裏須要生成client和server各組件certificate，代替kubernetes admin user生成client證書。

首先在master1創建/etc/etcd/ssl目錄，然後進入目錄進行如下操做：

$ mkdir -p /etc/etcd/ssl && cd /etc/etcd/ssl
$ export PKI_URL="https://kairen.github.io/files/manual-v1.8/pki"

下載ca-config.json和etcd-ca-csr.json：

$ wget "${PKI_URL}/ca-config.json" "${PKI_URL}/etcd-ca-csr.json"
$ cfssl gencert -initca etcd-ca-csr.json | cfssljson -bare etcd-ca
$ ls etcd-ca*.pem
etcd-ca-key.pem  etcd-ca.pem

下載etcd-csr.json並生成Etcd certificate證書：

$ wget "${PKI_URL}/etcd-csr.json"
$ cfssl gencert \
  -ca=etcd-ca.pem \
  -ca-key=etcd-ca-key.pem \
  -config=ca-config.json \
  -profile=kubernetes \
  etcd-csr.json | cfssljson -bare etcd

$ ls etcd*.pem
etcd-ca-key.pem  etcd-ca.pem  etcd-key.pem  etcd.pem

若是節點IP不一樣，須要修改 etcd-csr.json的hosts

完成後刪除沒必要要的文件：

$ rm -rf *.json

並確認/etc/etcd/ssl包含：

$ ls /etc/etcd/ssl
etcd-ca.csr  etcd-ca-key.pem  etcd-ca.pem  etcd.csr  etcd-key.pem  etcd.pem

Etcd的安裝和設置

首先在master1節點下載Etcd，解壓到/opt安裝：

$ export ETCD_URL="https://github.com/coreos/etcd/releases/download"
$ cd && wget -qO- --show-progress "${ETCD_URL}/v3.2.9/etcd-v3.2.9-linux-amd64.tar.gz" | tar -zx
$ mv etcd-v3.2.9-linux-amd64/etcd* /usr/local/bin/ && rm -rf etcd-v3.2.9-linux-amd64

完成後新建Etcd Group和User，並設定Etcd目錄：

$ groupadd etcd && useradd -c "Etcd user" -g etcd -s /sbin/nologin -r etcd

下載etcd相關配置，咱們未來管理Etcd：

$ export ETCD_CONF_URL="https://kairen.github.io/files/manual-v1.8/master"
$ wget "${ETCD_CONF_URL}/etcd.conf" -O /etc/etcd/etcd.conf
$ wget "${ETCD_CONF_URL}/etcd.service" -O /lib/systemd/system/etcd.service

若是沒用本文準備部分的IP，請用本身的IP代替 172.16.35.12

創建var 存放數據，而後啓動Etcd服務：

$ mkdir -p /var/lib/etcd && chown etcd:etcd -R /var/lib/etcd /etc/etcd
$ systemctl enable etcd.service && systemctl start etcd.service

經過如下命令驗證：

$ export CA="/etc/etcd/ssl"
$ ETCDCTL_API=3 etcdctl \
    --cacert=${CA}/etcd-ca.pem \
    --cert=${CA}/etcd.pem \
    --key=${CA}/etcd-key.pem \
    --endpoints="https://172.16.35.12:2379" \
    endpoint health
# output
https://172.16.35.12:2379 is healthy: successfully committed proposal: took = 641.36µs

Kubernetes Master

Master是Kubernetes的大總管，經過apiserver、Controller manager以及Scheduler管理全部節點。

本部分將下載Kubernetes並安裝到master1節點上，而後生成相關TLS certificates和CA，供集羣組件使用。

下載Kubernetes組件

# Download Kubernetes
$ export KUBE_URL="https://storage.googleapis.com/kubernetes-release/release/v1.8.6/bin/linux/amd64"
$ wget "${KUBE_URL}/kubelet" -O /usr/local/bin/kubelet
$ wget "${KUBE_URL}/kubectl" -O /usr/local/bin/kubectl
$ chmod +x /usr/local/bin/kubelet /usr/local/bin/kubectl

# Download CNI
$ mkdir -p /opt/cni/bin && cd /opt/cni/bin
$ export CNI_URL="https://github.com/containernetworking/plugins/releases/download"
$ wget -qO- --show-progress "${CNI_URL}/v0.6.0/cni-plugins-amd64-v0.6.0.tgz" | tar -zx

創建集羣CA和certificates

與Etcd部分原理同樣，操做也截然不同，首先在master1創建pki目錄，並進入目錄執行：

$ mkdir -p /etc/kubernetes/pki && cd /etc/kubernetes/pki
$ export PKI_URL="https://kairen.github.io/files/manual-v1.8/pki"
$ export KUBE_APISERVER="https://172.16.35.12:6443"

下載ca-config.json和etcd-ca-csr.json：

$ wget "${PKI_URL}/ca-config.json" "${PKI_URL}/ca-csr.json"
$ cfssl gencert -initca ca-csr.json | cfssljson -bare ca
$ ls ca*.pem
ca-key.pem  ca.pem

API server certificate

下載apiserver-csr.json，生成kube-apiserver certificate證書：

$ wget "${PKI_URL}/apiserver-csr.json"
$ cfssl gencert \
  -ca=ca.pem \
  -ca-key=ca-key.pem \
  -config=ca-config.json \
  -hostname=10.96.0.1,172.16.35.12,127.0.0.1,kubernetes.default \
  -profile=kubernetes \
  apiserver-csr.json | cfssljson -bare apiserver

$ ls apiserver*.pem
apiserver-key.pem  apiserver.pem

若是節點IP不一樣，須要修改 -hostname

Front proxy certificate

下載front-proxy-ca-csr.json，生成Front proxy CA，Front proxy主要用在API aggregator上：

$ wget "${PKI_URL}/front-proxy-ca-csr.json"
$ cfssl gencert \
  -initca front-proxy-ca-csr.json | cfssljson -bare front-proxy-ca

$ ls front-proxy-ca*.pem
front-proxy-ca-key.pem  front-proxy-ca.pem

下載front-proxy-client-csr.json，生成front-proxy-client證書：

$ wget "${PKI_URL}/front-proxy-client-csr.json"
$ cfssl gencert \
  -ca=front-proxy-ca.pem \
  -ca-key=front-proxy-ca-key.pem \
  -config=ca-config.json \
  -profile=kubernetes \
  front-proxy-client-csr.json | cfssljson -bare front-proxy-client

$ ls front-proxy-client*.pem
front-proxy-client-key.pem  front-proxy-client.pem

Bootstrap Token

手工方式生成CA很是麻煩，只適合少許機器，每次簽證時都須要綁定Node IP，隨着機器增長會帶來不少的不便，所以這裏使用TLS Bootstrapping的方式來進行受權，由apiserver自動爲符合條件的Node發送證書受權加入集羣。

作法是在kubelet啓動時，向kuber-apiserver傳送TLS Bootstrapping請求，而kube-apiserver驗證kubelet請求的token是否與設定的同樣，若是同樣則自動生成Kuberlet證書和密鑰。具體做法能夠參考TLS bootstrapping。

首先生成BOOTSTRAP_TOKEN，並創建bootstrap.conf的kubeconfig：

$ export BOOTSTRAP_TOKEN=$(head -c 16 /dev/urandom | od -An -t x | tr -d ' ')
$ cat <<EOF > /etc/kubernetes/token.csv
${BOOTSTRAP_TOKEN},kubelet-bootstrap,10001,"system:kubelet-bootstrap"
EOF

# bootstrap set-cluster
$ kubectl config set-cluster kubernetes \
    --certificate-authority=ca.pem \
    --embed-certs=true \
    --server=${KUBE_APISERVER} \
    --kubeconfig=../bootstrap.conf

# bootstrap set-credentials
$ kubectl config set-credentials kubelet-bootstrap \
    --token=${BOOTSTRAP_TOKEN} \
    --kubeconfig=../bootstrap.conf

# bootstrap set-context
$ kubectl config set-context default \
    --cluster=kubernetes \
    --user=kubelet-bootstrap \
   --kubeconfig=../bootstrap.conf

# bootstrap set default context
$ kubectl config use-context default --kubeconfig=../bootstrap.conf

若是想用CA的方式來認證，能夠參考 Kubelet certificate

Admin certificate

下載admin-csr.json，並生成admin certificate證書：

$ wget "${PKI_URL}/admin-csr.json"
$ cfssl gencert \
  -ca=ca.pem \
  -ca-key=ca-key.pem \
  -config=ca-config.json \
  -profile=kubernetes \
  admin-csr.json | cfssljson -bare admin

$ ls admin*.pem
admin-key.pem  admin.pem

而後執行一下命令生成名爲admin.conf的kubeconfig：

# admin set-cluster
$ kubectl config set-cluster kubernetes \
    --certificate-authority=ca.pem \
    --embed-certs=true \
    --server=${KUBE_APISERVER} \
    --kubeconfig=../admin.conf

# admin set-credentials
$ kubectl config set-credentials kubernetes-admin \
    --client-certificate=admin.pem \
    --client-key=admin-key.pem \
    --embed-certs=true \
    --kubeconfig=../admin.conf

# admin set-context
$ kubectl config set-context kubernetes-admin@kubernetes \
    --cluster=kubernetes \
    --user=kubernetes-admin \
    --kubeconfig=../admin.conf

# admin set default context
$ kubectl config use-context kubernetes-admin@kubernetes \
    --kubeconfig=../admin.conf

Controller manager certificate

下載manager-csr.json，並生成kube-controller-manager certificate證書：

$ wget "${PKI_URL}/manager-csr.json"
$ cfssl gencert \
  -ca=ca.pem \
  -ca-key=ca-key.pem \
  -config=ca-config.json \
  -profile=kubernetes \
  manager-csr.json | cfssljson -bare controller-manager

$ ls controller-manager*.pem

若是節點IP不一樣，須要修改 manager-csr.json的hosts

而後執行命令生成名爲controller-manager.conf的kubeconfig：

# controller-manager set-cluster
$ kubectl config set-cluster kubernetes \
    --certificate-authority=ca.pem \
    --embed-certs=true \
    --server=${KUBE_APISERVER} \
    --kubeconfig=../controller-manager.conf

# controller-manager set-credentials
$ kubectl config set-credentials system:kube-controller-manager \
    --client-certificate=controller-manager.pem \
    --client-key=controller-manager-key.pem \
    --embed-certs=true \
    --kubeconfig=../controller-manager.conf

# controller-manager set-context
$ kubectl config set-context system:kube-controller-manager@kubernetes \
    --cluster=kubernetes \
    --user=system:kube-controller-manager \
    --kubeconfig=../controller-manager.conf

# controller-manager set default context
$ kubectl config use-context system:kube-controller-manager@kubernetes \
    --kubeconfig=../controller-manager.conf

Scheduler certificate

下載scheduler-csr.json，生成kube-scheduler certificate證書：

$ wget "${PKI_URL}/scheduler-csr.json"
$ cfssl gencert \
  -ca=ca.pem \
  -ca-key=ca-key.pem \
  -config=ca-config.json \
  -profile=kubernetes \
  scheduler-csr.json | cfssljson -bare scheduler

$ ls scheduler*.pem
scheduler-key.pem  scheduler.pem

若是節點IP不一樣，須要修改 scheduler-csr.json的hosts

而後執行一下命令生成名爲scheduler.conf的kubeconfig：

# scheduler set-cluster
$ kubectl config set-cluster kubernetes \
    --certificate-authority=ca.pem \
    --embed-certs=true \
    --server=${KUBE_APISERVER} \
    --kubeconfig=../scheduler.conf

# scheduler set-credentials
$ kubectl config set-credentials system:kube-scheduler \
    --client-certificate=scheduler.pem \
    --client-key=scheduler-key.pem \
    --embed-certs=true \
    --kubeconfig=../scheduler.conf

# scheduler set-context
$ kubectl config set-context system:kube-scheduler@kubernetes \
    --cluster=kubernetes \
    --user=system:kube-scheduler \
    --kubeconfig=../scheduler.conf

# scheduler set default context
$ kubectl config use-context system:kube-scheduler@kubernetes \
    --kubeconfig=../scheduler.conf

Kubelet master certificate

下載kubelet-csr.json，並生成master node certificate證書：

$ wget "${PKI_URL}/kubelet-csr.json"
$ sed -i 's/$NODE/master1/g' kubelet-csr.json
$ cfssl gencert \
  -ca=ca.pem \
  -ca-key=ca-key.pem \
  -config=ca-config.json \
  -hostname=master1,172.16.35.12 \
  -profile=kubernetes \
  kubelet-csr.json | cfssljson -bare kubelet

$ ls kubelet*.pem
kubelet-key.pem  kubelet.pem

$NODE須要隨節點名稱不一樣而改變

而後執行一下命令生成名爲kubelet.conf的kubeconfig：

# kubelet set-cluster
$ kubectl config set-cluster kubernetes \
    --certificate-authority=ca.pem \
    --embed-certs=true \
    --server=${KUBE_APISERVER} \
    --kubeconfig=../kubelet.conf

# kubelet set-credentials
$ kubectl config set-credentials system:node:master1 \
    --client-certificate=kubelet.pem \
    --client-key=kubelet-key.pem \
    --embed-certs=true \
    --kubeconfig=../kubelet.conf

# kubelet set-context
$ kubectl config set-context system:node:master1@kubernetes \
    --cluster=kubernetes \
    --user=system:node:master1 \
    --kubeconfig=../kubelet.conf

# kubelet set default context
$ kubectl config use-context system:node:master1@kubernetes \
    --kubeconfig=../kubelet.conf

Service account key

Service account不須要CA認證，也就不須要CA來作Service account key的檢查，這裏咱們創建一組private和public的密鑰供Service account key使用：

$ openssl genrsa -out sa.key 2048 $ openssl rsa -in sa.key -pubout -out sa.pub $ ls sa.* sa.key sa.pub

完成後刪除沒必要要文件：

$ rm -rf *.json *.csr

確認/etc/kubernetes和/etc/kubernetes/pki包含如下文件：

$ ls /etc/kubernetes/
admin.conf  bootstrap.conf  controller-manager.conf  kubelet.conf  pki  scheduler.conf  token.csv

$ ls /etc/kubernetes/pki
admin-key.pem  apiserver-key.pem  ca-key.pem  controller-manager-key.pem  front-proxy-ca-key.pem  front-proxy-client-key.pem  kubelet-key.pem  sa.key  scheduler-key.pem
admin.pem      apiserver.pem      ca.pem      controller-manager.pem      front-proxy-ca.pem      front-proxy-client.pem      kubelet.pem      sa.pub  scheduler.pem

安裝Kubernetes 核心元件

下載Kubernetes核心組件Yaml文件，這裏咱們利用Kubernetes Statics Pod來創建Master核心組件，所以下載全部Static Pod文件到etc/kubernetes/manifests目錄「

$ export CORE_URL="https://kairen.github.io/files/manual-v1.8/master"
$ mkdir -p /etc/kubernetes/manifests && cd /etc/kubernetes/manifests
$ for FILE in apiserver manager scheduler; do
    wget "${CORE_URL}/${FILE}.yml.conf" -O ${FILE}.yml
  done

一樣的，若是IP與本文IP準備不一樣的話，須要修改 apiserver.yml、 manager.yml、`
scheduler.yml`
apiserver中的NodeRestriction請參考Using Node Authorization

生成一個用來加密Etcd的key

$ head -c 32 /dev/urandom | base64
SUpbL4juUYyvxj3/gonV5xVEx8j769/99TSAf8YT/sQ=

在/etc/kubernetes/目錄創建encryption.yml的加密YAML文件：

$ cat <<EOF > /etc/kubernetes/encryption.yml
kind: EncryptionConfig
apiVersion: v1
resources:
  - resources:
      - secrets
    providers:
      - aescbc:
          keys:
            - name: key1
              secret: SUpbL4juUYyvxj3/gonV5xVEx8j769/99TSAf8YT/sQ=
      - identity: {}
EOF

Etcd加密可參考 Encrypting data at rest

在/etc/kubernetes/目錄創建audit-policy.yml的auditing policay YAML文件：

$ cat <<EOF > /etc/kubernetes/audit-policy.yml
apiVersion: audit.k8s.io/v1beta1
kind: Policy
rules:
- level: Metadata
EOF

audit policy請參考 Audit

下載kubelet.service相關文件來管理kubelet：

$ export KUBELET_URL="https://kairen.github.io/files/manual-v1.8/master"
$ mkdir -p /etc/systemd/system/kubelet.service.d
$ wget "${KUBELET_URL}/kubelet.service" -O /lib/systemd/system/kubelet.service
$ wget "${KUBELET_URL}/10-kubelet.conf" -O /etc/systemd/system/kubelet.service.d/10-kubelet.conf

若 cluster-dns或 cluster-domain有變更，須要修改 10-kubelet.conf

最後創建var並啓動kubelet服務：

$ mkdir -p /var/lib/kubelet /var/log/kubernetes
$ systemctl enable kubelet.service && systemctl start kubelet.service

完成後須要一段時間來下載鏡像文件並啓動組件：

$ watch netstat -ntlp
tcp        0      0 127.0.0.1:10248         0.0.0.0:*               LISTEN      23012/kubelet
tcp        0      0 127.0.0.1:10251         0.0.0.0:*               LISTEN      22305/kube-schedule
tcp        0      0 127.0.0.1:10252         0.0.0.0:*               LISTEN      22529/kube-controll
tcp6       0      0 :::6443                 :::*                    LISTEN      22956/kube-apiserve

看到上述信息即代表服務啓動正常，若是出現問題可經過docker cli查看

完成後，複製admin kubeconfig並經過如下命令驗證：

$ cp /etc/kubernetes/admin.conf ~/.kube/config
$ kubectl get cs
NAME                 STATUS    MESSAGE              ERROR
etcd-0               Healthy   {"health": "true"}
scheduler            Healthy   ok
controller-manager   Healthy   ok

$ kubectl get node
NAME      STATUS     ROLES     AGE       VERSION
master1   NotReady   master    1m        v1.8.6

$ kubectl -n kube-system get po
NAME                              READY     STATUS    RESTARTS   AGE
kube-apiserver-master1            1/1       Running   0          4m
kube-controller-manager-master1   1/1       Running   0          4m
kube-scheduler-master1            1/1       Running   0          4m

確認服務可以執行logs等命令：

$ kubectl -n kube-system logs -f kube-scheduler-master1
Error from server (Forbidden): Forbidden (user=kube-apiserver, verb=get, resource=nodes, subresource=proxy) ( pods/log kube-apiserver-master1)

出現403 Forbidden問題代表 kube-apiserver user並無nodes的權限

因爲上述權限問題，咱們須要創建一個apiserver-to-kubelet-rbac.yml來定義權限，以供咱們執行logs、exec等命令：

$ cd /etc/kubernetes/
$ export URL="https://kairen.github.io/files/manual-v1.8/master"
$ wget "${URL}/apiserver-to-kubelet-rbac.yml.conf" -O apiserver-to-kubelet-rbac.yml
$ kubectl apply -f apiserver-to-kubelet-rbac.yml

# 測試 logs
$ kubectl -n kube-system logs -f kube-scheduler-master1
...
I1031 03:22:42.527697       1 leaderelection.go:184] successfully acquired lease kube-system/kube-scheduler

Kubernetes Node

Node運行容器實例的節點，即工做節點。本部分咱們會下載Kubernetes binary並創建node 的certificate來提供給節點註冊認證用。Kubernetes使用Node Authorizer來提供Authorization mode，這種受權模式會替Kubelet生成API request。

開始前，咱們先在master1將須要的ca和cert複製到Node節點上：

$ for NODE in node1 node2; do
    ssh ${NODE} "mkdir -p /etc/kubernetes/pki/"
    ssh ${NODE} "mkdir -p /etc/etcd/ssl"
    # Etcd ca and cert
    for FILE in etcd-ca.pem etcd.pem etcd-key.pem; do
      scp /etc/etcd/ssl/${FILE} ${NODE}:/etc/etcd/ssl/${FILE}
    done
    # Kubernetes ca and cert
    for FILE in pki/ca.pem pki/ca-key.pem bootstrap.conf; do
      scp /etc/kubernetes/${FILE} ${NODE}:/etc/kubernetes/${FILE}
    done
  done

下載Kubernetes 元件

首先獲取全部須要執行的文件：

# Download Kubernetes
$ export KUBE_URL="https://storage.googleapis.com/kubernetes-release/release/v1.8.6/bin/linux/amd64"
$ wget "${KUBE_URL}/kubelet" -O /usr/local/bin/kubelet
$ chmod +x /usr/local/bin/kubelet

# Download CNI
$ mkdir -p /opt/cni/bin && cd /opt/cni/bin
$ export CNI_URL="https://github.com/containernetworking/plugins/releases/download"
$ wget -qO- --show-progress "${CNI_URL}/v0.6.0/cni-plugins-amd64-v0.6.0.tgz" | tar -zx

設定Kubernetes node

下載Kubernetes相關文件，包括drop-in file、systemd service等：

$ export KUBELET_URL="https://kairen.github.io/files/manual-v1.8/node"
$ mkdir -p /etc/systemd/system/kubelet.service.d
$ wget "${KUBELET_URL}/kubelet.service" -O /lib/systemd/system/kubelet.service
$ wget "${KUBELET_URL}/10-kubelet.conf" -O /etc/systemd/system/kubelet.service.d/10-kubelet.conf

若是 cluster-dns或 cluster-domain有改變的話，須要修改10-kubelet.conf

而後在全部node創建var，並啓動kubelet服務：

$ mkdir -p /var/lib/kubelet /var/log/kubernetes /etc/kubernetes/manifests
$ systemctl enable kubelet.service && systemctl start kubelet.service

受權Kubernetes Node

重複完成全部節點後，在master1節點創建ClusterRoleBinding（由於咱們採用的是TLS Bootstrapping）：

$ kubectl create clusterrolebinding kubelet-bootstrap \
    --clusterrole=system:node-bootstrapper \
    --user=kubelet-bootstrap

在master進行驗證，咱們能夠看到節點處於pending：

$ kubectl get csr
NAME                                                   AGE       REQUESTOR           CONDITION
node-csr-YWf97ZrLCTlr2hmXsNLfjVLwaLfZRsu52FRKOYjpcBE   2s        kubelet-bootstrap   Pending
node-csr-eq4q6ffOwT4yqYQNU6sT7mphPOQdFN6yulMVZeu6pkE   2s        kubelet-bootstrap   Pending

經過kubectl，容許節點加入集羣：

$ kubectl get csr | awk '/Pending/ {print $1}' | xargs kubectl certificate approve
certificatesigningrequest "node-csr-YWf97ZrLCTlr2hmXsNLfjVLwaLfZRsu52FRKOYjpcBE" approved
certificatesigningrequest "node-csr-eq4q6ffOwT4yqYQNU6sT7mphPOQdFN6yulMVZeu6pkE" approved

$ kubectl get csr
NAME                                                   AGE       REQUESTOR           CONDITION
node-csr-YWf97ZrLCTlr2hmXsNLfjVLwaLfZRsu52FRKOYjpcBE   30s       kubelet-bootstrap   Approved,Issued
node-csr-eq4q6ffOwT4yqYQNU6sT7mphPOQdFN6yulMVZeu6pkE   30s       kubelet-bootstrap   Approved,Issued

$ kubectl get no
NAME      STATUS     ROLES     AGE       VERSION
master1   NotReady   master    21m       v1.8.6
node1     NotReady   node      8s        v1.8.6
node2     NotReady   node      8s        v1.8.6

Kubernetes Core Addons 部署

完成以上全部步驟，咱們還須要安裝一些插件，好比kube-dns、kube-proxy等等。

Kube-proxy addon

Kube-proxy是實現Service的關鍵組件，kube-proxy會在每一個節點上執行，而後監聽API Server的Service和Endpoint變化，並根據變化執行iptables實現網絡轉發。

這裏咱們須要DaemonSet來執行，並須要生成一些certificate。

首先在master1下載kube-proxy-csr.json，並生成kube-proxy certificate證書：

$ export PKI_URL="https://kairen.github.io/files/manual-v1.8/pki"
$ cd /etc/kubernetes/pki
$ wget "${PKI_URL}/kube-proxy-csr.json" "${PKI_URL}/ca-config.json"
$ cfssl gencert \
  -ca=ca.pem \
  -ca-key=ca-key.pem \
  -config=ca-config.json \
  -profile=kubernetes \
  kube-proxy-csr.json | cfssljson -bare kube-proxy

$ ls kube-proxy*.pem
kube-proxy-key.pem  kube-proxy.pem

而後經過如下命令生成名爲`kube-proxy.conf·的kubeconfig：

# kube-proxy set-cluster
$ kubectl config set-cluster kubernetes \
    --certificate-authority=ca.pem \
    --embed-certs=true \
    --server="https://172.16.35.12:6443" \
    --kubeconfig=../kube-proxy.conf

# kube-proxy set-credentials
$ kubectl config set-credentials system:kube-proxy \
    --client-key=kube-proxy-key.pem \
    --client-certificate=kube-proxy.pem \
    --embed-certs=true \
    --kubeconfig=../kube-proxy.conf

# kube-proxy set-context
$ kubectl config set-context system:kube-proxy@kubernetes \
    --cluster=kubernetes \
    --user=system:kube-proxy \
    --kubeconfig=../kube-proxy.conf

# kube-proxy set default context
$ kubectl config use-context system:kube-proxy@kubernetes \
    --kubeconfig=../kube-proxy.conf

刪除沒必要要的文件：

$ rm -rf *.json

確認/etc/kubernetes有如下文件：

$ ls /etc/kubernetes/
admin.conf        bootstrap.conf           encryption.yml  kube-proxy.conf  pki             token.csv
audit-policy.yml  controller-manager.conf  kubelet.conf    manifests        scheduler.conf

在master1上將kube-proxy相關文件複製到Node節點上：

$ for NODE in node1 node2; do
    echo "--- $NODE ---"
    for FILE in pki/kube-proxy.pem pki/kube-proxy-key.pem kube-proxy.conf; do
      scp /etc/kubernetes/${FILE} ${NODE}:/etc/kubernetes/${FILE}
    done
  done

完成後，在master1經過kubectl創建kube-proxy daemon：

$ export ADDON_URL="https://kairen.github.io/files/manual-v1.8/addon"
$ mkdir -p /etc/kubernetes/addons && cd /etc/kubernetes/addons
$ wget "${ADDON_URL}/kube-proxy.yml.conf" -O kube-proxy.yml
$ kubectl apply -f kube-proxy.yml
$ kubectl -n kube-system get po -l k8s-app=kube-proxy
NAME               READY     STATUS    RESTARTS   AGE
kube-proxy-bpp7q   1/1       Running   0          47s
kube-proxy-cztvh   1/1       Running   0          47s
kube-proxy-q7mm4   1/1       Running   0          47s

Kube-dns addon

Kube DNS是Kubernetes集羣內部Pod之間通訊的重要插件，容許Pod經過Domain Name連接Service，主要由Kube DNS與Sky DNS組合而成，經過Kube DNS監聽Service與Endpoint變化，來提供給Sky DNS信息以更新解析位址。

安裝只須要在master1經過kubectl創建kube-dns deployment便可：

$ export ADDON_URL="https://kairen.github.io/files/manual-v1.8/addon"
$ wget "${ADDON_URL}/kube-dns.yml.conf" -O kube-dns.yml
$ kubectl apply -f kube-dns.yml
$ kubectl -n kube-system get po -l k8s-app=kube-dns
NAME                        READY     STATUS    RESTARTS   AGE
kube-dns-6cb549f55f-h4zr5   0/3       Pending   0          40s

Calico Network 安裝與設定

Calico是一款純3層協議(不須要Overlay 網路)，已與各類雲原平生臺有良好的整合，在每一個節點節點利用Linux Kernel實現高效的vRouter來負責數據轉發，而當數據中心複雜度增長時，能夠用BGP route reflector來達成。

首先在master1經過kubectl創建Calico policy controller：

$ export CALICO_CONF_URL="https://kairen.github.io/files/manual-v1.8/network"
$ wget "${CALICO_CONF_URL}/calico-controller.yml.conf" -O calico-controller.yml
$ kubectl apply -f calico-controller.yml
$ kubectl -n kube-system get po -l k8s-app=calico-policy
NAME                                        READY     STATUS    RESTARTS   AGE
calico-policy-controller-5ff8b4549d-tctmm   0/1       Pending   0          5s

若是節點IP不一樣，須要修改calico-controller.yml的ETCD_ENDPOINTS

在`master1·下載Calico CLI工具：

$ wget https://github.com/projectcalico/calicoctl/releases/download/v1.6.1/calicoctl
$ chmod +x calicoctl && mv calicoctl /usr/local/bin/

而後在全部節點下載Calico，並執行如下命令：

$ export CALICO_URL="https://github.com/projectcalico/cni-plugin/releases/download/v1.11.0"
$ wget -N -P /opt/cni/bin ${CALICO_URL}/calico
$ wget -N -P /opt/cni/bin ${CALICO_URL}/calico-ipam
$ chmod +x /opt/cni/bin/calico /opt/cni/bin/calico-ipam

接着在全部節點下載CNI plugins以及calico-node.service：

$ mkdir -p /etc/cni/net.d
$ export CALICO_CONF_URL="https://kairen.github.io/files/manual-v1.8/network"
$ wget "${CALICO_CONF_URL}/10-calico.conf" -O /etc/cni/net.d/10-calico.conf
$ wget "${CALICO_CONF_URL}/calico-node.service" -O /lib/systemd/system/calico-node.service

若是節點IP不一樣，須要修改10-calico.conf的etcd_endpoints
若是部署機器是虛擬機，須要修改calico-node.service，並在IP_AUTODETECTION_METHOD (包含IP6)部分指定綁定的網卡，以避免預設綁定到NAT網路上

以後在全部節點啓動Calico-node：

$ systemctl enable calico-node.service && systemctl start calico-node.service

在master1查看Calico nodes：

$ cat <<EOF > ~/calico-rc
export ETCD_ENDPOINTS="https://172.16.35.12:2379"
export ETCD_CA_CERT_FILE="/etc/etcd/ssl/etcd-ca.pem"
export ETCD_CERT_FILE="/etc/etcd/ssl/etcd.pem"
export ETCD_KEY_FILE="/etc/etcd/ssl/etcd-key.pem"
EOF

$ . ~/calico-rc
$ calicoctl get node -o wide
NAME      ASN       IPV4              IPV6
master1   (64512)   172.16.35.12/24
node1     (64512)   172.16.35.10/24
node2     (64512)   172.16.35.11/24

查看pending的pod是否已執行：

$ kubectl -n kube-system get po
NAME                                        READY     STATUS    RESTARTS   AGE
calico-policy-controller-5ff8b4549d-tctmm   1/1       Running   0          4m
kube-apiserver-master1                      1/1       Running   0          20m
kube-controller-manager-master1             1/1       Running   0          20m
kube-dns-6cb549f55f-h4zr5                   3/3       Running   0          5m
kube-proxy-fnrkb                            1/1       Running   0          6m
kube-proxy-l72bq                            1/1       Running   0          6m
kube-proxy-m6rfw                            1/1       Running   0          6m
kube-scheduler-master1                      1/1       Running   0          20m

省事的作法是用Standard Hosted方式安裝。

Kubernetes Extra Addons 部署

本部分說明如何部署官方經常使用的addons，例如dashboard、heapster等。

Dashboard addon

Dashboard是Kubernetes官方開發的儀表板，讓咱們以能夠i 經過web-based方式管理kubernetes集羣。

在master1經過kubectl創建kubernetes dashboard便可：

$ kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml
$ kubectl -n kube-system get po,svc -l k8s-app=kubernetes-dashboard
NAME                                      READY     STATUS    RESTARTS   AGE
po/kubernetes-dashboard-747c4f7cf-md5m8   1/1       Running   0          56s

NAME                       TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)   AGE
svc/kubernetes-dashboard   ClusterIP   10.98.120.209   <none>        443/TCP   56s

這邊會額外創建一個名稱爲open-api的Cluster Role Binding，放拜年測試使用，通常狀況下不開啓（開啓會存取全部API）。

$ cat <<EOF | kubectl create -f -
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: open-api
  namespace: ""
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
  - apiGroup: rbac.authorization.k8s.io
    kind: User
    name: system:anonymous
EOF

管理者能夠針對特定使用者來開放API存取權限，這裏咱們爲了方便直接綁在cluster-admin cluster role。

1.7版本後的Dashboard再也不提供全部權限，須要創建一個service account來綁定cluster-admin role：

$ kubectl -n kube-system create sa dashboard
$ kubectl create clusterrolebinding dashboard --clusterrole cluster-admin --serviceaccount=kube-system:dashboard
$ SECRET=$(kubectl -n kube-system get sa dashboard -o yaml | awk '/dashboard-token/ {print $3}')
$ kubectl -n kube-system describe secrets ${SECRET} | awk '/token:/{print $2}'
eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJkYXNoYm9hcmQtdG9rZW4tdzVocmgiLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC5uYW1lIjoiZGFzaGJvYXJkIiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZXJ2aWNlLWFjY291bnQudWlkIjoiYWJmMTFjYzMtZjRlYi0xMWU3LTgzYWUtMDgwMDI3NjdkOWI5Iiwic3ViIjoic3lzdGVtOnNlcnZpY2VhY2NvdW50Omt1YmUtc3lzdGVtOmRhc2hib2FyZCJ9.Xuyq34ci7Mk8bI97o4IldDyKySOOqRXRsxVWIJkPNiVUxKT4wpQZtikNJe2mfUBBD-JvoXTzwqyeSSTsAy2CiKQhekW8QgPLYelkBPBibySjBhJpiCD38J1u7yru4P0Pww2ZQJDjIxY4vqT46ywBklReGVqY3ogtUQg-eXueBmz-o7lJYMjw8L14692OJuhBjzTRSaKW8U2MPluBVnD7M2SOekDff7KpSxgOwXHsLVQoMrVNbspUCvtIiEI1EiXkyCNRGwfnd2my3uzUABIHFhm0_RZSmGwExPbxflr8Fc6bxmuz-_jSdOtUidYkFIzvEWw2vRovPgs3MXTv59RwUw

複製token，而後貼到Kubernetes dashboard

Heapster addon

Heapster是Kubernetes社區維護的容器集羣監控和分析工具。Heapster會從Kubernetes apiserver取得全部Node數據，而後再經過Node獲取kubelet上的數據，最後再將全部收集到數據送到Heapster後臺儲存InfluxDB，最後利用Grafana抓取InfluxDB數據源來進行展現。

在master1經過kubectl來創建kubernetes monitor便可：

$ export ADDON_URL="https://kairen.github.io/files/manual-v1.8/addon"
$ wget ${ADDON_URL}/kube-monitor.yml.conf -O kube-monitor.yml
$ kubectl apply -f kube-monitor.yml
$ kubectl -n kube-system get po,svc
NAME                                           READY     STATUS    RESTARTS   AGE
...
po/heapster-74fb5c8cdc-62xzc                   4/4       Running   0          7m
po/influxdb-grafana-55bd7df44-nw4nc            2/2       Running   0          7m

NAME                       TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)             AGE
...
svc/heapster               ClusterIP   10.100.242.225   <none>        80/TCP              7m
svc/monitoring-grafana     ClusterIP   10.101.106.180   <none>        80/TCP              7m
svc/monitoring-influxdb    ClusterIP   10.109.245.142   <none>        8083/TCP,8086/TCP   7m
···

簡單部署Nginx 服務

Kubernetes能夠選擇使用指令直接創建應用和服務，或者咱們能夠寫YAML、JSON文件來配置，以下所示：

$ kubectl run nginx --image=nginx --port=80
$ kubectl expose deploy nginx --port=80 --type=LoadBalancer --external-ip=172.16.35.12
$ kubectl get svc,po
NAME             TYPE           CLUSTER-IP      EXTERNAL-IP    PORT(S)        AGE
svc/kubernetes   ClusterIP      10.96.0.1       <none>         443/TCP        1h
svc/nginx        LoadBalancer   10.97.121.243   172.16.35.12   80:30344/TCP   22s

NAME                        READY     STATUS    RESTARTS   AGE
po/nginx-7cbc4b4d9c-7796l   1/1       Running   0          28s       192.160.57.181   ,172.16.35.12   80:32054/TCP   21s

這裏type能夠選擇NodePort和LoadBalancer在本地裸機部署，二者差別在於NodePort只映射Host port到Container port，而LoadBalancer則繼承NodePort額外映射Host target port到Container port

擴展服務數量

最後，咱們能夠經過如下方式來擴展服務數量：

$ kubectl scale deploy nginx --replicas=2

$ kubectl get pods -o wide
NAME                    READY     STATUS    RESTARTS   AGE       IP             NODE
nginx-158599303-0h9lr   1/1       Running   0          25s       10.244.100.5   node2
nginx-158599303-k7cbt   1/1       Running   0          1m        10.244.24.3    node1

相關閱讀