How to Setup Jenkins Slaves Using Password and ssh Keys

Jenkins SSH slave setup

One of the best features of Jenkins is its distributed nature. You can configure multiple build slaves for better segregation and scalability. For example, you might want to test a cross-platform code base with a different operating system. In this case, you can configure different OS slaves and run the job against them. Also, a distributed architecture will reduce the load on the master server.

Setup Slaves on Jenkins

In this guide, I will walk you through the steps for setting up the Jenkins slaves.

There are two ways of authentication for setting up the Jenkins slaves.

  1. Using username and password
  2. Using ssh keys.

Jenkins Slave Prerequisites

You need to do the following in the slave machines before adding it to the master.

  1. Java should be installed on your slave machine.
  2. We should have a valid user who can perform the required tasks on the server. (preferably a sudo user if your job required elevated privileges)

Create a Jenkins User

It is recommended to execute all Jenkins jobs as jenkins user on the slave nodes.

Note: I am using Ubuntu machine as a slave. The steps will be same for other Linux flavours as well

1. Create a jenkins user and a password using the following command.

sudo adduser jenkins --shell /bin/bash

Type a password when prompted. The above commands should create a user and a home directory named jenkins under “/home”.

2. Now, login as jenkins user.

su jenkins

3. Create a “jenkins_slave” directory under /home/jenkins.

mkdir /home/jenkins/jenkins_slave

Note: You can read more about adding Linux sudo users from here -> Adding sudo users and permissions on Linux

Setting up Jenkins slaves using username and password

1. Head over to Jenkins dashboard –> Manage Jenkins –> Manage Nodes

2. Select new node option.

jenkins 2.0 node config

3. Give it a name, select the “permanent agent” option and click ok.

jenkins 2.0 add node

4. Enter the details as shown in the image below and save it. For credential box, click the add button and enter the slaves jenkins username and password (For logging into the slave machine) that you created during the slave configuration. To know what each option means, click the question mark at the right side of each text box.

jenkins 2.0 node credentials

4. Once you click save, Jenkins will automatically connect to the slave machine and will configure an agent.

Like this, you can add multiple nodes as slaves.

Setting up Jenkins slaves using ssh keys

1. Login to the slave server as a jenkins user.

2. Create a .ssh directory and cd into the directory.

mkdir ~/.ssh && cd ~/.ssh

3. Create an ssh key pair using the following command. Press enter for all the defaults when prompted.

ssh-keygen -t rsa -C "The access key for Jenkins slaves"

4. Add the public to authorized_keys file using the following command.

cat > ~/.ssh/authorized_keys

5. Now, copy the contents of the private key to the clipboard.

cat id_rsa

Add the private key to Jenkins credential list

1. Go to jenkins dashboard –> credentials –> Global credentials –> add credentials , select and enter all the credentials as shown below and click ok.

jenkins 2.0 ssh credentials

Setup slaves from Jenkins master

1. Follow the first 3 steps we did for slave configuration using username and password.

2. Follow all the configuration in the 4th step. But this time, for the launch method, select the credential you created with the ssh key.

Test the slaves

To test the slave, create a sample project and select the option as shown below. You need to select the node using the label option. If you start to type the letter the node list will show up.

jenkins 2.0 selecting slaves


In this tutorial, we learned how to set up slaves for Jenkins. Ther is no complex step involved in this configuration. When it comes to automating the process, you will need scripts and Jenkins CLI to this. I will cover that in future posts.

Share if you like it and leave a comment if you have queries!!

  1. Just an aside, but it might be worth noting in your instructions that you must have Java also installed on the slave. I didn’t realise this, and it caught me!

  2. Is possible just copy the Master’s public key to Slave simply by ‘ssh-copy-id’? You mentioned that create the ssh key on slave then copy the private key to master. Thanks

  3. Nice blog !! Is there any way to configure the emails from the slave node? I meant , if I have jobs running in the slave node with editable email plugin. Whenever, I trigger the email it should be sending emails uopn slave email config but not Master.

  4. I tried to connect via “Setting Up Slaves Using Ssh Keys” I got below error log and Node still offline. Do you have any idea for this ?

    [06/05/17 16:48:03] [SSH] Opening SSH connection to
    Key exchange was not finished, connection is closed. There was a problem while connecting to
    at com.trilead.ssh2.Connection.connect(
    at com.trilead.ssh2.Connection.connect(
    at com.trilead.ssh2.Connection.connect(
    at hudson.plugins.sshslaves.SSHLauncher.openConnection(
    at hudson.plugins.sshslaves.SSHLauncher$
    at hudson.plugins.sshslaves.SSHLauncher$
    at java.util.concurrent.ThreadPoolExecutor.runWorker(
    at java.util.concurrent.ThreadPoolExecutor$
    Caused by: Key exchange was not finished, connection is closed.
    at com.trilead.ssh2.transport.KexManager.getOrWaitForConnectionInfo(
    at com.trilead.ssh2.transport.TransportManager.getConnectionInfo(
    at com.trilead.ssh2.Connection.connect(
    … 9 more
    Caused by: Cannot read full block, EOF reached.
    at com.trilead.ssh2.crypto.cipher.CipherInputStream.getBlock(
    at com.trilead.ssh2.transport.TransportConnection.receiveMessage(
    at com.trilead.ssh2.transport.TransportManager.receiveLoop(
    at com.trilead.ssh2.transport.TransportManager$
    … 1 more
    [06/05/17 16:48:03] Launch failed – cleaning up connection
    [06/05/17 16:48:03] [SSH] Connection closed.


  5. Hello,

    Do you have to have Jenkins installed on the slave servers for this connection via SSH to work? I tried without the Jenkins install on the slaves and it did not work. My guess is that it should work because this is a system connection problem and Jenkins really doesn’t assist in any kind of way with this process. You should just need it on the master.

  6. Under execute shell i had given shell script path and file name eg:” sh /home/sachin/Myscripts/”.Will this transferred to slave pc and run?.In my case it wont

  7. Hey bibin,thanks for the blog.
    How to run a shell script in slave jenkins that configured in jenkins master or developers PC?

    1. Under Build –> Add a Build Step, you will find an option called “execute shell”. You can add your scripts there.

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