该消息意味着您唯一可用的节点（恰好是Jenkins控制器）没有您在此块中的代理上要求的标签docker：

agent {
    docker {
        label 'docker'
        image 'python:3.7'
    }
}

将标签docker添加到控制器，然后重新启动Jenkins（识别标签更改是必需的，尽管这让我很惊讶。这可能是标记控制器本身的特性，因为如果可能，您应该避免调度作业在那里运行）解决了这个问题。
标签前：

Started by user admin
Running in Durability level: MAX_SURVIVABILITY
[Pipeline] Start of Pipeline
[Pipeline] node
Running on Jenkins in /var/jenkins_home/workspace/test
[Pipeline] {
[Pipeline] stage
[Pipeline] { (install pip dependencies)
[Pipeline] node
Still waiting to schedule task
‘Jenkins’ doesn’t have label ‘docker’
Aborted by admin
[Pipeline] // node
[Pipeline] }
[Pipeline] // stage
[Pipeline] }
[Pipeline] // node
[Pipeline] End of Pipeline
Finished: ABORTED

标签后，重新开始前：

Started by user admin
Running in Durability level: MAX_SURVIVABILITY
[Pipeline] Start of Pipeline
[Pipeline] node
Running on Jenkins in /var/jenkins_home/workspace/test
[Pipeline] {
[Pipeline] stage
[Pipeline] { (install pip dependencies)
[Pipeline] node
Still waiting to schedule task
‘Jenkins’ doesn’t have label ‘docker’
Aborted by admin
[Pipeline] // node
[Pipeline] }
[Pipeline] // stage
[Pipeline] }
[Pipeline] // node
[Pipeline] End of Pipeline
Finished: ABORTED

重启后，突出显示我的控制器没有安装Docker

Started by user admin
Running in Durability level: MAX_SURVIVABILITY
[Pipeline] Start of Pipeline
[Pipeline] node
Running on Jenkins in /var/jenkins_home/workspace/test
[Pipeline] {
[Pipeline] stage
[Pipeline] { (install pip dependencies)
[Pipeline] node
Running on Jenkins in /var/jenkins_home/workspace/test@2
[Pipeline] {
[Pipeline] isUnix
[Pipeline] sh
+ docker inspect -f . python:3.7
/var/jenkins_home/workspace/test@2@tmp/durable-4a9f38a7/script.sh: 1: /var/jenkins_home/workspace/test@2@tmp/durable-4a9f38a7/script.sh: docker: not found
[Pipeline] isUnix
[Pipeline] sh
+ docker pull python:3.7
/var/jenkins_home/workspace/test@2@tmp/durable-58d19d02/script.sh: 1: /var/jenkins_home/workspace/test@2@tmp/durable-58d19d02/script.sh: docker: not found
[Pipeline] }
[Pipeline] // node
[Pipeline] }
[Pipeline] // stage
[Pipeline] }
[Pipeline] // node
[Pipeline] End of Pipeline
ERROR: script returned exit code 127
Finished: FAILURE

您的管道将如下所示：

pipeline {
  agent {
    label 'docker'
  }
  stages {
    stage('install pip dependencies') {
      steps {
        withEnv(["HOME=${env.WORKSPACE}"]) {
          sh'''
            pip install virtualenv
            virtualenv venv
            pip install -r requirements.txt
          '''
        }
      }
    }
  }
}

但是在你需要按照这些步骤让Jenkins把码头集装箱当作奴隶来运行之前：

• 在你主机上安装Docker;
• 添加jenkins到Docker组：sudo usermod -aG docker jenkins
• 将文件/lib/systemd/system/docker.service中的ExecStart=/usr/bin/dockerd行修改为以下ExecStart=/usr/bin/dockerd -H tcp://0.0.0.0:2375 -H unix:///var/run/docker.sock -H fd:// -s overlay2 --containerd=/run/containerd/containerd.sock
• 运行sudo systemctl daemon-reload和sudo systemctl restart docker
• 在Jenkins中配置Docker部分：manage Jenkins -> manage nodes and clouds -> configure clouds -> add a new cloud -> docker在Docker URL字段中键入tcp://127.0.0.1:2375 (or 4243)或unix:///var/run/docker.sock。配置代理，设置任何标签并在管道中使用它。

也许你需要关闭selinux。