kubernetes实践：安装jenkins slave
一、安装Jenkins
1. 安装存储服务器
找一台服务器搭建一台nfs服务器
系统：Ubuntu 16.04
IP：172.18.1.13
apt install nfs-common nfs-kernel-server -y
#配置挂载信息
cat /etc/exports
/data/k8s *(rw,sync,no_root_squash)
#给目录添加权限
chmod -R 777 /data/k8s
#启动
/etc/init.d/nfs-kernel-server start
#开机启动
systemctl enable nfs-kernel-server
2. kubernetes集群安装Jenkins
#该目录下是jenkins.mytest.io为测试域名的自签密钥
ls jenkins.mytest.io/
cacerts.pem cacerts.srl cakey.pem create_self-signed-cert.sh jenkins.mytest.io.crt jenkins.mytest.io.csr jenkins.mytest.io.key openssl.cnf tls.crt tls.key
---
cd jenkins.mytest.io
#创建Jenkins所在的namespace
kubectl create namespace kube-ops
#将密文添加到kube-ops里面
# 服务证书和私钥密文
kubectl -n kube-ops create \
secret tls tls-jenkins-ingress \
--cert=./tls.crt \
--key=./tls.key
# ca证书密文
kubectl -n kube-ops create secret \
generic tls-ca \
--from-file=cacerts.pem3. 创建Jenkins
cat jenkins-pvc.yaml
---
apiVersion: v1
kind: PersistentVolume
metadata:
name: jenkins-pv
spec:
capacity:
storage: 20Gi
accessModes:
- ReadWriteMany
persistentVolumeReclaimPolicy: Delete
nfs:
server: 172.18.1.13
path: /data/k8s
---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: jenkins-pvc
namespace: kube-ops
spec:
accessModes:
- ReadWriteMany
resources:
requests:
storage: 20Gicat rbac.yaml
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: jenkins
namespace: kube-ops
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: jenkins
rules:
- apiGroups: ["extensions", "apps"]
resources: ["deployments"]
verbs: ["create", "delete", "get", "list", "watch", "patch", "update"]
- apiGroups: [""]
resources: ["services"]
verbs: ["create", "delete", "get", "list", "watch", "patch", "update"]
- apiGroups: [""]
resources: ["pods"]
verbs: ["create","delete","get","list","patch","update","watch"]
- apiGroups: [""]
resources: ["pods/exec"]
verbs: ["create","delete","get","list","patch","update","watch"]
- apiGroups: [""]
resources: ["pods/log"]
verbs: ["get","list","watch"]
- apiGroups: [""]
resources: ["secrets"]
verbs: ["get"]
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
name: jenkins
namespace: kube-ops
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: jenkins
subjects:
- kind: ServiceAccount
name: jenkins
namespace: kube-opscat jenkins.yaml
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: jenkins
namespace: kube-ops
spec:
template:
metadata:
labels:
app: jenkins
spec:
terminationGracePeriodSeconds: 10
serviceAccount: jenkins
containers:
- name: jenkins
image: jenkins/jenkins:lts
imagePullPolicy: IfNotPresent
ports:
- containerPort: 8080
name: web
protocol: TCP
- containerPort: 50000
name: agent
protocol: TCP
resources:
limits:
cpu: 1000m
memory: 1Gi
requests:
cpu: 500m
memory: 512Mi
livenessProbe:
httpGet:
path: /login
port: 8080
initialDelaySeconds: 60
timeoutSeconds: 5
failureThreshold: 12
readinessProbe:
httpGet:
path: /login
port: 8080
initialDelaySeconds: 60
timeoutSeconds: 5
failureThreshold: 12
volumeMounts:
- name: jenkinshome
subPath: jenkins
mountPath: /var/jenkins_home
env:
- name: LIMITS_MEMORY
valueFrom:
resourceFieldRef:
resource: limits.memory
divisor: 1Mi
- name: JAVA_OPTS
value: -Xmx$(LIMITS_MEMORY)m -XshowSettings:vm -Dhudson.slaves.NodeProvisioner.initialDelay=0 -Dhudson.slaves.NodeProvisioner.MARGIN=50 -Dhudson.slaves.NodeProvisioner.MARGIN0=0.85 -Duser.timezone=Asia/Shanghai
securityContext:
fsGroup: 1000
volumes:
- name: jenkinshome
persistentVolumeClaim:
claimName: jenkins-pvc
---
apiVersion: v1
kind: Service
metadata:
name: jenkins
namespace: kube-ops
labels:
app: jenkins
spec:
selector:
app: jenkins
type: NodePort
ports:
- name: web
port: 8080
targetPort: web
nodePort: 30002
- name: agent
port: 50000
targetPort: agent
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: jenkins-lb
namespace: kube-ops
spec:
tls:
- secretName: tls-jenkins-ingress
rules:
- host: jenkins.mytest.io
http:
paths:
- backend:
serviceName: jenkins
servicePort: 8080创建Jenkins
kubectl create -f pvc.yaml
kubectl create -f rbac.yaml
kubectl create -f jenkins.yaml二、jenkins配置
在/etc/hosts配置域名解析
kube-ip jenkins.mytest.io1. 初始化配置
打开https://jenkins.mytes.io
安装插件，选择默认即可
2. 插件配置
采用Jenkins里面的kubernetes插件，让Jenkins可以调用kubernetes生成Jenkins-slave
https://github.com/jenkinsci/kubernetes-plugin
2.1 安装kubernetes插件
Manage Jenkins -> Manage Plugins -> Available -> Kubernetes plugin 勾选安装即可。
2.2 配置kubernetes插件功能
-
Manage Jenkins —> Configure System —> (拖到最下方)Add a new cloud —> 选择 Kubernetes，然后填写 Kubernetes 和 Jenkins 配置信息。
-
kubernetes地址采用了kube的服务器发现https://kubernetes.default.svc.cluster.local
-
namespace填kube-ops，然后点击Test Connection，如果出现 Connection test successful 的提示信息证明 Jenkins 已经可以和 Kubernetes 系统正常通信
- Jenkins URL 地址：http://jenkins.kube-ops.svc.cluster.local:8080
2.3 配置 kubernetes Pod Template
其实就是配置 Jenkins Slave 运行的 Pod 模板，命名空间我们同样是用 kube-ops，Labels 这里也非常重要，对于后面执行 Job 的时候需要用到该值，然后我们这里使用的是 cnych/jenkins:jnlp 这个镜像，这个镜像是在官方的 jnlp 镜像基础上定制的，加入了 kubectl 等一些实用的工具。
2.4 添加容器的挂载卷
另外需要注意我们这里需要在下面挂载两个主机目录，一个是 /var/run/docker.sock，该文件是用于 Pod 中的容器能够共享宿主机的 Docker，这就是大家说的 docker in docker 的方式，Docker 二进制文件我们已经打包到上面的镜像中了，另外一个目录下 /root/.kube 目录，我们将这个目录挂载到容器的 /home/jenkins/.kube 目录下面这是为了让我们能够在 Pod 的容器中能够使用 kubectl 工具来访问我们的 Kubernetes 集群，方便我们后面在 Slave Pod 部署 Kubernetes 应用。
2.5 添加账号
另外一些同学在配置了后运行 Slave Pod 的时候出现了权限问题，因为 Jenkins Slave Pod 中没有配置权限，所以需要配置上 ServiceAccount，在 Slave Pod 配置的地方点击下面的高级，添加上对应的 ServiceAccount 即可：
测试的时候不添加账号会告知没有权限
在容器模板高级里面添加kubernetes集群中创建的jenkins账号
三、测试
创建一个测试任务
在pipeline的框里面添加一下内容
def label = "jnlp-slave"
podTemplate(inheritFrom: 'jnlp-slave', instanceCap: 0, label: 'jnlp-slave', name: '', namespace: 'kube-ops', nodeSelector: '', podRetention: always(), serviceAccount: '', workspaceVolume: emptyDirWorkspaceVolume(false), yaml: '') {
node(label) {
container('jnlp-slave'){
stage('Run shell') {
sh 'docker info'
sh 'kubectl get pods -n kube-ops'
}
}
}
}开始构建任务
构建任务输出
Started by user admin
Running in Durability level: MAX_SURVIVABILITY
[Pipeline] Start of Pipeline
[Pipeline] podTemplate
[Pipeline] {
[Pipeline] node
Still waiting to schedule task
‘Jenkins’ doesn’t have label ‘jnlp-slave’
Agent jnlp-slave-tbdnl is provisioned from template Kubernetes Pod Template
Agent specification [Kubernetes Pod Template] (jnlp-slave):
* [jnlp-slave] cnych/jenkins:jnlp
Running on jnlp-slave-tbdnl in /home/jenkins/workspace/test-jnlp-slave
[Pipeline] {
[Pipeline] container
[Pipeline] {
[Pipeline] stage
[Pipeline] { (Run shell)
[Pipeline] sh
+ docker info
Containers: 15
Running: 12
Paused: 0
Stopped: 3
Images: 12
Server Version: 18.09.6
Storage Driver: overlay2
Backing Filesystem: extfs
Supports d_type: true
Native Overlay Diff: false
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: bb71b10fd8f58240ca47fbb579b9d1028eea7c84
runc version: 2b18fe1d885ee5083ef9f0838fee39b62d653e30
init version: fec3683
Security Options:
apparmor
seccomp
Profile: default
Kernel Version: 4.15.0-1049-azure
Operating System: Ubuntu 16.04.6 LTS
OSType: linux
Architecture: x86_64
CPUs: 2
Total Memory: 7.768GiB
Name: test-kube-node-04
ID: YFTJ:FVHK:TAF3:HTAJ:HJ2A:5SFW:73RW:VQY5:Y64U:UGIR:KMJ2:XPRL
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): false
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
127.0.0.0/8
Registry Mirrors:
https://kv3qfp85.mirror.aliyuncs.com/
Live Restore Enabled: false
WARNING: No swap limit support
[Pipeline] sh
+ kubectl get pods -n kube-ops
NAME READY STATUS RESTARTS AGE
jenkins-6b874b8d7-q28h4 1/1 Running 0 3h
jnlp-slave-tbdnl 2/2 Running 0 15s
[Pipeline] }
[Pipeline] // stage
[Pipeline] }
[Pipeline] // container
[Pipeline] }
[Pipeline] // node
[Pipeline] }
[Pipeline] // podTemplate
[Pipeline] End of Pipeline
Finished: SUCCESS结束语
上面步骤大部分都是根据阳明博客上的《基于 Jenkins 的 CI/CD(一)》思路跟进，但是由于环境和自己认知问题，会出现各种出错，憋了一天，没什么进展。
后来只能根据kubectl -n kube-ops logs -f jenkins-xxxxx的命令一点点查出来的，搜过很多帖子大概思路一致，但是无法解决本质问题，如果跑不起来，再高端也是个没有用，后来根据kubernetes-plugin的github，具体读了遍结合自己报的错一点一点调整过来，总算搞出来了。
具体参考了以下几遍优秀的文章：
基于 Jenkins 的 CI/CD(一)（阳明老师的文章很棒）
kubernetes Jenkins gitlab搭建CI/CD环境 (二)
GitHub-Jenkins-kubernetes-plugin：jenkinsci/kubernetes-plugin
rancher官网: 在Kubernetes上部署和扩展Jenkins