最近,有部分用户飘了……
觉得Rainbond提供的既简洁、又易用、而且生产就绪的Kubernets体验不过瘾……
想要挑战一下Kubernetes全手动部署……
并在凌晨一点拨通了客服小哥的电话……
因此本着不重复造轮子并且关爱客服小哥身心健康的主张,我们搬来了Kairen的精彩教程——
开始
Kubernetes官方提供了多种安装方式Picking the right solution,本文将以全手动安装方式
来部署Kubernetes v1.8.x版本,学习和了解Kubernetes的构建流程。
版本明细:
- Kubernetes v1.8.6
- CNI v0.6.0
- Etcd v3.2.9
- Calico v2.6.2
- Docker v17.10.0-ce
准备
系统:ubuntu 16.x
或 centos 7.x
节点:
- 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为主要控制节点和部署节点,node为应用运行节点
所有操作均为root
安装前需确认以下事项:
- 确认所有节点之间网络互通,master1 SSH登入其他节点为passwordless
- 确认防火墙和SELinux已关闭,如centos:
$ systemctl stop firewalld && systemctl disable firewalld
$ setenforce 0
$ vim /etc/selinux/config
SELINUX=disabled
- 所有节点需要设置
/etc/host
解析到所有主机
...
172.16.35.10 node1
172.16.35.11 node2
172.16.35.12 master1
-
所有节点都需要安装docker
$ curl -fsSL "https://get.docker.com/" | sh
注意:centos安装docker完成后需要执行:
$ systemctl enable docker && systemctl start docker
编辑
/lib/systemd/system/docker.service
,在ExecStart=..
加入:ExecStartPost=/sbin/iptables -A FORWARD -s 0.0.0.0/0 -j ACCEPT
完成后重启docker服务:
$ systemctl daemon-reload && systemctl restart docker
-
所有节点都需要设定
/etc/sysctl.d/k8s.conf
系统参数$ 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安装
CFSSL
工具,用来建立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
安装Kubernetes之前,我们需要完成一些必要的系统配置,高可用共享配置和服务发现存储Etcd便是其中的重要一环,节点会从Etcd中获取所需数据。
建立集群CA和certificates
这里需要生成client和server各组件certificate,代替kubernetes admin user生成client证书。
首先在master1
建立/etc/etcd/ssl
目录,而后进入目录进行以下操作:
$ mkdir -p /etc/etcd/ssl && cd /etc/etcd/ssl
$ export PKI_URL="https://kairen.github.io/files/manual-v1.8/pki"
下载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
下载etcd-csr.json
并生成Etcd certificate证书:
$ 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
如果节点IP不同,需要修改etcd-csr.json
的hosts
完成后删除不必要的文件:
$ rm -rf *.json
并确认/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的安装和设置
首先在master1
节点下载Etcd,解压到/opt
安装:
$ 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
完成后新建Etcd Group和User,并设定Etcd目录:
$ groupadd etcd && useradd -c "Etcd user" -g etcd -s /sbin/nologin -r etcd
下载etcd相关配置,我们将来管理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
如果没用本文准备部分的IP,请用自己的IP代替172.16.35.12
建立var 存放数据,然后启动Etcd服务:
$ mkdir -p /var/lib/etcd && chown etcd:etcd -R /var/lib/etcd /etc/etcd
$ systemctl enable etcd.service && systemctl start etcd.service
通过以下命令验证:
$ 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的大总管,通过apiserver
、Controller manager
以及Scheduler
管理所有节点。
本部分将下载Kubernetes并安装到master1节点上,然后生成相关TLS certificates和CA,供集群组件使用。
下载Kubernetes组件
# 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
建立集群CA和certificates
与Etcd部分原理一样,操作也大相径庭,首先在master1
建立pki
目录,并进入目录执行:
$ 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"
下载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
下载apiserver-csr.json
,生成kube-apiserver certificate
证书:
$ 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
如果节点IP不同,需要修改-hostname
Front proxy certificate
下载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
下载front-proxy-client-csr.json
,生成front-proxy-client证书:
$ 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非常麻烦,只适合少量机器,每次签证时都需要绑定Node IP,随着机器增加会带来很多的不便,因此这里使用TLS Bootstrapping的方式来进行授权,由apiserver自动为符合条件的Node发送证书授权加入集群。
做法是在kubelet启动时,向kuber-apiserver传送TLS Bootstrapping请求,而kube-apiserver验证kubelet请求的token是否与设定的一样,如果一样则自动生成Kuberlet证书和密钥。具体作法可以参考TLS bootstrapping。
首先生成BOOTSTRAP_TOKEN
,并建立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
如果想用CA的方式来认证,可以参考Kubelet certificate
Admin certificate
下载admin-csr.json
,并生成admin certificate
证书:
$ 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
然后执行一下命令生成名为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
下载manager-csr.json
,并生成kube-controller-manager certificate
证书:
$ 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
如果节点IP不同,需要修改manager-csr.json
的hosts
然后执行命令生成名为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
下载scheduler-csr.json
,生成kube-scheduler certificate证书:
$ 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
如果节点IP不同,需要修改scheduler-csr.json
的hosts
然后执行一下命令生成名为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
下载kubelet-csr.json
,并生成master node certificate证书:
$ 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
需要随节点名称不同而改变
然后执行一下命令生成名为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不需要CA认证,也就不需要CA来做Service account key的检查,这里我们建立一组private和public的密钥供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
完成后删除不必要文件:
$ rm -rf *.json *.csr
确认/etc/kubernetes
和/etc/kubernetes/pki
包含以下文件:
$ 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
安装Kubernetes 核心元件
下载Kubernetes核心组件Yaml文件,这里我们利用Kubernetes Statics Pod来建立Master核心组件,因此下载所有Static Pod文件到etc/kubernetes/manifests
目录“
$ 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
同样的,如果IP与本文IP准备不同的话,需要修改apiserver.yml
、manager.yml
、`
scheduler.yml`apiserver中的
NodeRestriction
请参考Using Node Authorization
生成一个用来加密Etcd的key
$ head -c 32 /dev/urandom | base64
SUpbL4juUYyvxj3/gonV5xVEx8j769/99TSAf8YT/sQ=
在/etc/kubernetes/
目录建立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加密可参考Encrypting data at rest
在/etc/kubernetes/
目录建立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请参考Audit
下载kubelet.service
相关文件来管理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
有变动,需要修改10-kubelet.conf
最后建立var并启动kubelet服务:
$ mkdir -p /var/lib/kubelet /var/log/kubernetes
$ systemctl enable kubelet.service && systemctl start kubelet.service
完成后需要一段时间来下载镜像文件并启动组件:
$ 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
看到上述信息即表明服务启动正常,如果出现问题可通过docker cli查看
完成后,复制admin kubeconfig并通过以下命令验证:
$ 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
确认服务能够执行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)
出现403 Forbidden问题表明kube-apiserver user
并没有nodes的权限
由于上述权限问题,我们需要建立一个apiserver-to-kubelet-rbac.yml
来定义权限,以供我们执行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运行容器实例的节点,即工作节点。本部分我们会下载Kubernetes binary并建立node 的certificate来提供给节点注册认证用。Kubernetes使用Node Authorizer来提供Authorization mode,这种授权模式会替Kubelet生成API request。
开始前,我们先在master1
将需要的ca和cert复制到Node节点上:
$ 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
下载Kubernetes 元件
首先获取所有需要执行的文件:
# 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
设定Kubernetes node
下载Kubernetes相关文件,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
如果cluster-dns
或cluster-domain
有改变的话,需要修改10-kubelet.conf
然后在所有node建立var,并启动kubelet服务:
$ mkdir -p /var/lib/kubelet /var/log/kubernetes /etc/kubernetes/manifests
$ systemctl enable kubelet.service && systemctl start kubelet.service
授权Kubernetes Node
重复完成所有节点后,在master1节点建立ClusterRoleBinding(因为我们采用的是TLS Bootstrapping):
$ kubectl create clusterrolebinding kubelet-bootstrap \
--clusterrole=system:node-bootstrapper \
--user=kubelet-bootstrap
在master进行验证,我们可以看到节点处于pending:
$ kubectl get csr
NAME AGE REQUESTOR CONDITION
node-csr-YWf97ZrLCTlr2hmXsNLfjVLwaLfZRsu52FRKOYjpcBE 2s kubelet-bootstrap Pending
node-csr-eq4q6ffOwT4yqYQNU6sT7mphPOQdFN6yulMVZeu6pkE 2s kubelet-bootstrap Pending
通过kubectl,允许节点加入集群:
$ 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
完成以上所有步骤,我们还需要安装一些插件,比如kube-dns、kube-proxy等等。
Kube-proxy addon
Kube-proxy是实现Service的关键组件,kube-proxy会在每个节点上执行,然后监听API Server的Service和Endpoint变化,并根据变化执行iptables实现网络转发。
这里我们需要DaemonSet来执行,并需要生成一些certificate。
首先在master1
下载kube-proxy-csr.json
,并生成kube-proxy certificate证书:
$ 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
然后通过以下命令生成名为`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
删除不必要的文件:
$ rm -rf *.json
确认/etc/kubernetes
有以下文件:
$ 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
上将kube-proxy相关文件复制到Node节点上:
$ 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
完成后,在master1
通过kubectl建立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集群内部Pod之间通信的重要插件,允许Pod通过Domain Name链接Service,主要由Kube DNS与Sky DNS组合而成,通过Kube DNS监听Service与Endpoint变化,来提供给Sky DNS信息以更新解析位址。
安装只需要在master1
通过kubectl建立kube-dns deployment即可:
$ 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 安装与设定
Calico是一款纯3层协议(不需要Overlay 网路),已与各种云原生平台有良好的整合,在每个节点节点利用Linux Kernel实现高效的vRouter来负责数据转发,而当数据中心复杂度增加时,可以用BGP route reflector来达成。
首先在master1
通过kubectl建立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
如果节点IP不同,需要修改calico-controller.yml的ETCD_ENDPOINTS
在`master1·下载Calico CLI工具:
$ wget https://github.com/projectcalico/calicoctl/releases/download/v1.6.1/calicoctl
$ chmod +x calicoctl && mv calicoctl /usr/local/bin/
然后在所有节点下载Calico,并执行以下命令:
$ 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
接着在所有节点下载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
如果节点IP不同,需要修改10-calico.conf的etcd_endpoints如果部署机器是虚拟机,需要修改calico-node.service,并在IP_AUTODETECTION_METHOD (包含IP6)部分指定绑定的网卡,以免预设绑定到NAT网路上
之后在所有节点启动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是否已执行:
$ 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
省事的做法是用Standard Hosted方式安装。
Kubernetes Extra Addons 部署
本部分说明如何部署官方常用的addons,例如dashboard、heapster等。
Dashboard addon
Dashboard是Kubernetes官方开发的仪表板,让我们以可以i 通过web-based方式管理kubernetes集群。
在master1
通过kubectl建立kubernetes dashboard即可:
$ 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
这边会额外建立一个名称为open-api
的Cluster Role Binding,放拜年测试使用,一般情况下不开启(开启会存取所有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
管理者可以针对特定使用者来开放API存取权限,这里我们为了方便直接绑在cluster-admin cluster role。
1.7版本后的Dashboard不再提供所有权限,需要建立一个service account来绑定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
复制token,然后贴到Kubernetes dashboard
Heapster addon
Heapster是Kubernetes社区维护的容器集群监控和分析工具。Heapster会从Kubernetes apiserver取得所有Node数据,然后再通过Node获取kubelet上的数据,最后再将所有收集到数据送到Heapster后台储存InfluxDB,最后利用Grafana抓取InfluxDB数据源来进行展示。
在master1
通过kubectl来建立kubernetes monitor即可:
$ 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
···
简单部署Nginx 服务
Kubernetes可以选择使用指令直接建立应用和服务,或者我们可以写YAML、JSON文件来配置,如下所示:
$ 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
这里type可以选择NodePort和LoadBalancer在本地裸机部署,两者差异在于NodePort只映射Host port到Container port,而LoadBalancer则继承NodePort额外映射Host target port到Container port
扩展服务数量
最后,我们可以通过以下方式来扩展服务数量:
$ 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
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