In Jenkins 2.x, the terminology has been modernized - what was previously called a "Dumb Slave" is now referred to as a "Permanent Agent". This change reflects Jenkins' move toward more inclusive language and better describes the actual functionality.

Here's how to create what you previously knew as a dumb slave:

1. Navigate to Manage Jenkins > Manage Nodes and Clouds
2. Click New Node
3. Enter a node name and select Permanent Agent
4. Configure the agent properties:

// Example of node configuration in Jenkinsfile
pipeline {
    agent {
        label 'your-agent-label'
    }
    stages {
        stage('Example') {
            steps {
                echo 'Running on the designated agent'
            }
        }
    }
}

When setting up your permanent agent, pay special attention to:

• Remote root directory: Workspace path on the agent machine
• Launch method: Choose between SSH, Java Web Start, or others
• Availability: Set to "Keep this agent online as much as possible"

If your agent fails to connect, verify:

# On Linux agents, check Java version
java -version

# Verify network connectivity from agent to master
ping jenkins-master.example.com
telnet jenkins-master.example.com 8080

For automation purposes, you can create nodes via Jenkins CLI:

java -jar jenkins-cli.jar -s http://your-jenkins/ create-node your-agent-name << EOF
<slave>
  <name>your-agent-name</name>
  <description>Agent description</description>
  <remoteFS>/path/to/workspace</remoteFS>
  <numExecutors>2</numExecutors>
  <mode>NORMAL</mode>
  <launcher class="hudson.slaves.JNLPLauncher" />
</slave>
EOF

• Use labels effectively to organize agents by capability
• Monitor agent load through the Jenkins metrics plugin
• Implement agent provisioning automation for dynamic scaling

If you're coming from older Jenkins versions (pre-2.0), you'll notice the term "Dumb Slave" has been replaced with "Permanent Agent" in the Jenkins UI. This isn't just cosmetic - it reflects architectural changes in how Jenkins handles distributed builds.

The process is essentially the same, just with updated terminology. Here's how to set up what was previously called a "Dumb Slave":

1. Navigate to Manage Jenkins > Manage Nodes and Clouds
2. Click New Node
3. Select Permanent Agent (this is the replacement for "Dumb Slave")

Here's a typical configuration for a Linux agent:

<slave>
  <name>linux-build-agent-01</name>
  <description>Ubuntu 20.04 build agent</description>
  <remoteFS>/var/jenkins</remoteFS>
  <numExecutors>2</numExecutors>
  <mode>NORMAL</mode>
  <retentionStrategy class="hudson.slaves.RetentionStrategy$Always"/>
  <launcher class="hudson.slaves.JNLPLauncher"/>
  <label>linux ubuntu amd64</label>
  <nodeProperties/>
</slave>

Modern Jenkins offers several connection options for agents:

If you're having trouble connecting your agent:

• Firewall issues: Ensure TCP port 50000 is open between master and agent
• Java version mismatch: Verify consistent Java versions
• Authentication problems: Check credentials and agent JNLP secret

For advanced configuration, you might need to modify the agent's jenkins-agent.xml:

<service>
  <id>jenkins-agent</id>
  <name>Jenkins Agent</name>
  <description>This service runs a Jenkins agent.</description>
  <executable>%BASE%\jre\bin\java.exe</executable>
  <arguments>-Xrs -jar "%BASE%\agent.jar" -jnlpUrl http://jenkins-server:8080/computer/agent-name/slave-agent.jnlp -secret your-secret-key</arguments>
</service>