本节详细讲述使用SSH连接以Docker方式启动的agents。

一、环境

假设Jenkins master已经安装好了。agent机器上docker环境也安装好了。

二、安装步骤

2.1 生成ssh key pair

在Jenkins master机器上执行以下命令，如果是以docker方式安装就在容器里面执行

$ ssh-keygen
Generating public/private rsa key pair.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa
Your public key has been saved in /root/.ssh/id_rsa.pub
The key fingerprint is:
SHA256:XqxxjqsLlvDD0ZHm9Y2iR7zC6IbsUlMEHo3ffy8TzGs
The key's randomart image is:
+---[RSA 3072]----+
|  o+             |
| ...o  .         |
|  .o .+ .        |
|    o+.+ o o     |
|  ... o.So* .    |
|  o+ = +.X=      |
| o oO + *..+     |
|. oo.o o .E .    |
| o... oo.. o     |
+----[SHA256]-----+

2.2 创建Jenkins SSH credential

1. 打开Jenkins dashboard
2. 在主菜单上点击Manage Jenkins，然后点击credentials 按钮
   
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3. 在global下拉框点击 Add Credentials

   
   
   image.png
4. 填写表单

• Kind: SSH Username with private key
• id: jenkins
• description: The jenkins ssh key
• username: jenkins（xia'magent容器的用户）
• Private Key: 从~/.ssh/id_rsa拷贝

• Passphrase: 如果私钥有密码保护就需要填入

  
  
  image.png

2.3 创建docker agent

使用 docker-ssh-agent image创建agent：

docker run -d --rm --name=agent1 -p 22:22 \
-e "JENKINS_AGENT_SSH_PUBKEY=[your-public-key]" \
jenkins/ssh-agent:alpine

[your-public-key]是ssh public key，可以从~/.ssh/id_rsa.pub获取

2.4 在Jenkins master建立agent1

在Jenkins dashboard一次点击Manage Jenkins ---> Manage Nodes and clouds ---> New Node输入agent的名称和类型（比如Name: agent1, Type: Permanent Agent），点击OK，填写以下表单

image.png

• Remote root directory; (e.g.: /home/jenkins )
• label; (e.g.: agent1 )
• usage; (e.g.: only build jobs with label expression…​)
• Launch method; (e.g.: Launch agents by SSH )
  • Host; (e.g.: localhost or your IP address )
  • Credentials; (e.g.: jenkins )
  • Host Key verification Strategy; (e.g.: Manually trusted key verification …​ )
  • JavaPath；这个选项必填/opt/java/openjdk/bin/java

然后点击保存，此时agent1已经注册到master，但是还是offline，点进去

image.png

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