[Discussion] Getting `jenkins` communication issue with docker daemon

[afzal442]

Hi @devopsjourney1! I have hard finding about setting up jenkins pipeline with docker agent. Since I have followed these steps from the docs here, but when I try to follow the steps from ur video, I am failing to create a label docker agent.

Is it necessary to install jenkins through docker to establish connection b/w docker host and jenkins server?

When I skip the docker installation as I have done through kubernetes and follow the docker socket connection like this docker network create jenkins and docker run -d --restart=always -p 127.0.0.1:2376:2375 --network jenkins -v /var/run/docker.sock:/var/run/docker.sock alpine/socat tcp-listen:2375,fork,reuseaddr unix-connect:/var/run/docker.sock, I still fail to make the connection successful. Any thoughts here plz?

[afzal442]

While during my investigation, I created a pipeline, but refused to build due to a failure. Here is my below pipeline script

 pipeline {
    agent any
    stages {
        stage('Build') {
            steps {
                echo "Building.."
            }
        }
        stage('Test') {
            steps {
                echo "Testing.."
                sh '''
                git version
                git clone https://github.com/devopsjourney1/jenkins-101
                cd jenkins-101
                cat Jenkinsfile
                '''
                sh "docker version"
            }
        }
        stage('Deliver') {
            steps {
                echo 'Deliver....'
                sh '''
                echo "doing delivery stuff.."
                '''
            }
        }
    }
}

Build error as

[Pipeline]
+ docker version
Client:
 Version:      17.05.0-ce
 API version:  1.29
 Go version:   go1.7.5
 Git commit:   89658be
 Built:        Fri May  5 15:36:11 2017
 OS/Arch:      linux/amd64
Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

[afzal442]

hi @devopsjourney1! It's been quite a while now. Maybe you were busy with ur works. Could take a look here and help me debug this issue? TYIA!

[RogerTaylor130]

run

sudo docker version

and attach the output

[afzal442]

hey @RogerTaylor130 here what I found

/var/jenkins_home/workspace/respip@tmp/durable-01d1605b/script.sh: 1: sudo: not found

[RogerTaylor130]

Hi, @afzal442

Can you post all the Jenkins logs since you got /var/jenkins_home/workspace/respip@tmp/durable-01d1605b/script.sh: 1: sudo: not found

You need to know,

• sudo not found is the sudo on your Linux machine has not been installed.
• Which node got selected since you use agent any
• As you figure out which node is selected then run sudo docker version on that node via ssh.

[afzal442]

To make it simpler, plz consider this pipeline

pipeline {
    agent any
    stages {
        stage('Build') {
            steps {
                echo "Building.."
            }
        }
        stage('Test') {
            steps {
                echo "Testing.."
                sh "sudo docker version"
            }
        }
        stage('Deliver') {
            steps {
                echo 'Deliver....'
                sh '''
                echo "doing delivery stuff.."
                '''
            }
        }
    }
}

LMK if u r able to run the abv pipeline.

I have sudo installed in my Linux m/c by the way.

Below is the full logs

Started by user [Afzal](http://localhost:8000/user/afzal442)
[Pipeline] Start of Pipeline
[Pipeline] node
Running on [Jenkins](http://localhost:8000/manage/computer/(built-in)/) in /var/jenkins_home/workspace/respip
[Pipeline] {
[Pipeline] stage
[Pipeline] { (Build)
[Pipeline] echo
Building..
[Pipeline] }
[Pipeline] // stage
[Pipeline] stage
[Pipeline] { (Test)
[Pipeline] echo
Testing..
[Pipeline] sh
+ sudo docker version
/var/jenkins_home/workspace/respip@tmp/durable-b2227a00/script.sh: 1: sudo: not found
[Pipeline] }
[Pipeline] // stage
[Pipeline] stage
[Pipeline] { (Deliver)
Stage "Deliver" skipped due to earlier failure(s)
[Pipeline] }
[Pipeline] // stage
[Pipeline] }
[Pipeline] // node
[Pipeline] End of Pipeline
ERROR: script returned exit code 127
Finished: FAILURE

Plz suggest how to debug this. Thanks

[RogerTaylor130]

Well. The pipeline looks fine to me but I did not test it.

Looks like your pipeline is running on the built-in node which is your localhost I think.

Try to run sudo docker version on your localhost. It equals what you did in the test stage` in the pipeline.

[afzal442]

Thanks for quick response.

Looks like your pipeline is running on the built-in node

Try to run sudo docker version on your localhost.

Sorry! How?

But if I ran docker version in the pipeline, it would show up like this Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

[RogerTaylor130]

SSH into your Jenkins machine and run sudo docker version.

Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running? This is probably because docker doesn't provide normal user permission to run the docker commands. You need the root user to run docker version

[afzal442]

I am just looping around;

$ sudo docker version
/bin/sh: 1: sudo: not found

Here you go, I hope you have read the comment abv. Thanks

Since I have followed these steps from the docs here, but when I try to follow the steps from ur video, I am failing to create a label docker agent.

[RogerTaylor130]

Not sure about the k8s installation. Just let u know your pipeline is called the mast node to run sudo docker version locally. Say your Jenkins machine is the docker container in the pod, your container does not have sudo installed for sure from the Jenkins log.

[afzal442]

Ah I see. I don't think sudo is installed in any container in any pod unless root access. By the way, what's abt node agent? Can I create new node agent against docker? I can't find help from docs as well. I am so much exhausted that I have watched almost every official videos abt docker but no chance. Any suggestions?

Edit: What would u say abt it https://www.jenkins.io/doc/book/pipeline/docker/ ?

[RogerTaylor130]

I am not sure how far you have gone with docker, k8s, jenkins... But jenkins does not have very close connection with docker and k8s. I suggest go with jenkins and docker first then k8s. Study a little bit deep since you don't know about some basic concepts of jenkins like node/agent... Well... I am not good as well so it's just my personal advice. Good lucky.

[shadycuz]

@afzal442 If you need docker in your K8's pod you will either have to run the pod with elevated privileges AND pass in the host machine's docker socket.

OR

You can install docker inside your container, which can be very challenging to do but is the better approach from a security perspective.

What you are going to have to do is create a customer jenkins docker container image that has the docker daemon installed. Once that is done you can look up instructions for creating on demand jenkins nodes/agents/runners using Kubernetes.

[afzal442]

Thanks @RogerTaylor130 for digging into it alongside me. I am flattered by your quick responses and suggestions. Again for your advice. 😄