DEV Community

Ruan Bekker
Ruan Bekker

Posted on

How to Setup a Concourse CI Server

#concourse #devops #linux #tutorial

concourse

Concourse is a Pipeline Based Continuous Integration System written in Go.

What is Concourse CI:

Concourse CI is a Continuous Integration Platform. Concourse enables you to construct pipelines with yaml configuration that can consist out of 3 core concepts that compose them:

  • tasks
  • resources
  • jobs

For more information about this have a look at their docs

What will we be doing today

We will setup a Concourse Server on Ubuntu 18.04 and run the traditional Hello, World pipeline

Setup the Server:

Concourse requires PostgresSQL for it's database (at least version 9.3)

$ apt update && apt upgrade -y
$ apt install postgresql postgresql-contrib -y
$ systemctl enable postgresql
Enter fullscreen mode Exit fullscreen mode

Create the Database and User for Concourse on your Postgres database:

$ sudo -u postgres createuser concourse
$ sudo -u postgres createdb --owner=concourse atc
Enter fullscreen mode Exit fullscreen mode

Download the Concourse Server Archive:

$ export CONCOURSE_VERSION=5.7.2
$ wget https://github.com/concourse/concourse/releases/download/v${CONCOURSE_VERSION}/concourse-${CONCOURSE_VERSION}-linux-amd64.tgz
Enter fullscreen mode Exit fullscreen mode

Extract the concourse archive:

$ tar -zxf concourse-${CONCOURSE_VERSION}-linux-amd64.tgz -C /usr/local
Enter fullscreen mode Exit fullscreen mode

Create the encryption keys:

$ mkdir /etc/concourse
$ ssh-keygen -t rsa -q -N '' -f /etc/concourse/tsa_host_key
$ ssh-keygen -t rsa -q -N '' -f /etc/concourse/worker_key
$ ssh-keygen -t rsa -q -N '' -f /etc/concourse/session_signing_key
$ cp /etc/concourse/worker_key.pub /etc/concourse/authorized_worker_keys
Enter fullscreen mode Exit fullscreen mode

Concourse Web Process Configuration:

$ EXT_IP=$(curl -s https://ip.ruan.dev)

$ cat > /etc/concourse/web_environment << EOF
CONCOURSE_ADD_LOCAL_USER=admin:admin
CONCOURSE_SESSION_SIGNING_KEY=/etc/concourse/session_signing_key
CONCOURSE_TSA_HOST_KEY=/etc/concourse/tsa_host_key
CONCOURSE_TSA_AUTHORIZED_KEYS=/etc/concourse/authorized_worker_keys
CONCOURSE_POSTGRES_HOST=127.0.0.1
CONCOURSE_POSTGRES_USER=concourse
CONCOURSE_POSTGRES_PASSWORD=concourse
CONCOURSE_POSTGRES_DATABASE=atc
CONCOURSE_MAIN_TEAM_LOCAL_USER=admin
CONCOURSE_EXTERNAL_URL=http://${EXT_IP}:8080
EOF
Enter fullscreen mode Exit fullscreen mode

Concourse Worker Process Configuration:

$ cat > /etc/concourse/worker_environment << EOF
CONCOURSE_WORK_DIR=/var/lib/concourse
CONCOURSE_TSA_HOST=127.0.0.1:2222
CONCOURSE_TSA_PUBLIC_KEY=/etc/concourse/tsa_host_key.pub
CONCOURSE_TSA_WORKER_PRIVATE_KEY=/etc/concourse/worker_key
EOF
Enter fullscreen mode Exit fullscreen mode

Create a Concourse user:

$ mkdir /var/lib/concourse
$ sudo adduser --system --group concourse
$ sudo chown -R concourse:concourse /etc/concourse /var/lib/concourse
$ sudo chmod 600 /etc/concourse/*_environment
Enter fullscreen mode Exit fullscreen mode

Create SystemD Unit Files, first for the Web Service:

$ cat > /etc/systemd/system/concourse-web.service << EOF
[Unit]
Description=Concourse CI web process (ATC and TSA)
After=postgresql.service

[Service]
User=concourse
Restart=on-failure
EnvironmentFile=/etc/concourse/web_environment
ExecStart=/usr/local/concourse/bin/concourse web

[Install]
WantedBy=multi-user.target
EOF
Enter fullscreen mode Exit fullscreen mode

Then the SystemD Unit File for the Worker Service:

$ cat  > /etc/systemd/system/concourse-worker.service << EOF
[Unit]
Description=Concourse CI worker process
After=concourse-web.service

[Service]
User=root
Restart=on-failure
EnvironmentFile=/etc/concourse/worker_environment
ExecStart=/usr/local/concourse/bin/concourse worker

[Install]
WantedBy=multi-user.target
EOF
Enter fullscreen mode Exit fullscreen mode

Create a postgres password for the concourse user:

$ cd /home/concourse/
$ sudo -u concourse psql atc
atc=> ALTER USER concourse WITH PASSWORD 'concourse';
atc=> \q
Enter fullscreen mode Exit fullscreen mode

Start and Enable the Services:

$ systemctl start concourse-web concourse-worker
$ systemctl enable concourse-web concourse-worker postgresql
$ systemctl status concourse-web concourse-worker

$ systemctl is-active concourse-worker concourse-web
active
active
Enter fullscreen mode Exit fullscreen mode

The listening ports should more or less look like the following:

$ netstat -tulpn

Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 127.0.0.1:5432          0.0.0.0:*               LISTEN      11290/postgres
tcp        0      0 127.0.0.1:7776          0.0.0.0:*               LISTEN      13040/concourse
tcp        0      0 127.0.0.1:7777          0.0.0.0:*               LISTEN      13118/gdn
tcp        0      0 127.0.0.1:7787          0.0.0.0:*               LISTEN      13040/concourse
tcp        0      0 127.0.0.1:7788          0.0.0.0:*               LISTEN      13040/concourse
tcp        0      0 127.0.0.1:8079          0.0.0.0:*               LISTEN      13039/concourse
tcp6       0      0 :::41299                :::*                    LISTEN      13039/concourse
tcp6       0      0 :::8888                 :::*                    LISTEN      13040/concourse
tcp6       0      0 ::1:5432                :::*                    LISTEN      11290/postgres
tcp6       0      0 :::35323                :::*                    LISTEN      13039/concourse
tcp6       0      0 :::2222                 :::*                    LISTEN      13039/concourse
tcp6       0      0 :::8080                 :::*                    LISTEN      13039/concourse
udp        0      0 0.0.0.0:54582           0.0.0.0:*                           13118/gdn
Enter fullscreen mode Exit fullscreen mode

Client Side:

When you access the UI on the external ip on port 8080:

image

After logging in, you should see a screen with no pipelines configured:

image

We require the fly cli client which is used to interact with concourse. On your local machine, download the fly archive, extract the archive and move the fly binary to your path.

I will by using the client for Mac, for alternate versions have a look at their releases page

$ export CONCOURSE_VERSION=5.7.2
$ wget https://github.com/concourse/concourse/releases/download/v${CONCOURSE_VERSION}/fly-${CONCOURSE_VERSION}-darwin-amd64.tgz
$ tar -xf fly-${CONCOURSE_VERSION}-darwin-amd64.tgz
$ sudo mv fly /usr/local/bin/fly
Enter fullscreen mode Exit fullscreen mode

Next, we need to setup our Concourse Target by Authenticating against our Concourse Endpoint, lets setup our target with the name ci:

$ fly -t ci login -c http://${EXT_IP}:8080
logging in to team 'main'

navigate to the following URL in your browser:

  http://136.244.102.215:8080/login?fly_port=49722

or enter token manually:
Enter fullscreen mode Exit fullscreen mode

Follow the URL and your target should be saved. Lets list our targets:

$ fly targets
name  url                        team  expiry
ci      http://136.244.102.215:8080  main  Wed, 18 Dec 2019 20:48:02 UTC
Enter fullscreen mode Exit fullscreen mode

Listing Registered Workers:

$ fly -t ci workers
name  containers  platform  tags  team  state    version  age
demo  0           linux     none  none  running  2.2      16m1s
Enter fullscreen mode Exit fullscreen mode

Listing Active Containers:

$ fly -t ci containers
handle  worker  pipeline  job  build #  build id  type  name  attempt
Enter fullscreen mode Exit fullscreen mode

Hello World Pipeline:

Let's create a basic pipeline, that will print out Hello, World!:

Our hello-world.yml

jobs:
- name: my-job
  plan:
  - task: say-hello
    config:
      platform: linux
      image_resource:
        type: docker-image
        source:
          repository: alpine
          tag: edge
      run:
        path: /bin/sh
        args:
        - -c
        - |
          echo "============="
          echo "Hello, World!"
          echo "============="
Enter fullscreen mode Exit fullscreen mode

Applying the configuration to our pipeline:

$ fly -t ci set-pipeline -p yeeehaa -c hello-world.yml
jobs:
  job my-job has been added:
    name: my-job
    plan:
    - task: say-hello
      config:
        platform: linux
        image_resource:
          type: docker-image
          source:
            repository: alpine
            tag: edge
        run:
          path: /bin/sh
          args:
          - -c
          - |
            echo "============="
            echo "Hello, World!"
            echo "============="

apply configuration? [yN]: y
pipeline created!
you can view your pipeline here: http:////136.244.102.215:8080/teams/main/pipelines/yeeehaa

the pipeline is currently paused. to unpause, either:
  - run the unpause-pipeline command
  - click play next to the pipeline in the web ui
Enter fullscreen mode Exit fullscreen mode

In the Web-UI we will see the pipeline that we created:

image

We can unpause the pipeline in the Web-UI, but since I like to do everything on cli as far as possible, I will unpause the pipeline via cli:

$ fly -t ci unpause-pipeline -p yeeehaa
unpaused 'yeeehaa'
Enter fullscreen mode Exit fullscreen mode

Now our Pipeline is unpaused, but since we did not specify any triggers, we need to manually trigger the pipeline to run, you can either via the WebUI, select your pipeline which in this case will be named yeeehaa and then select the job, which will be my-job then hit the + sign, which will trigger the pipeline.

I will be using the cli:

$ fly -t ci trigger-job --job yeeehaa/my-job
started yeeehaa/my-job #1
Enter fullscreen mode Exit fullscreen mode

Via the WebUI on http://${EXT_IP}:8080/teams/main/pipelines/yeeehaa/jobs/my-job/builds/1 you should see the Hello, World! output.

If you are running Concourse on Ubuntu 18 and you ran into this issue:

image

It's a DNS fix that you can apply by doing this:

$ sudo apt install resolvconf
$ echo -e "nameserver 8.8.4.4\nnameserver 8.8.8.8" > /etc/resolvconf/resolv.conf.d/head
$ sudo service resolvconf restart
Enter fullscreen mode Exit fullscreen mode

We can trigger our pipeline via the cli, we also have the option to see the output, so let's trigger it again, but this time passing the --watch flag:

$ fly -t ci trigger-job --job yeeehaa/my-job --watch
started yeeehaa/my-job #5

initializing
running /bin/sh -c echo "============="
echo "Hello, World!"
echo "============="

=============
Hello, World!
=============
succeeded
Enter fullscreen mode Exit fullscreen mode

Listing our Workers and Containers again:

$ fly -t ci workers
name   containers  platform  tags  team  state    version  age
demo   1           linux     none  none  running  2.2      45m32s

$ fly -t ci containers
handle                                worker            pipeline     job         handle                                worker  pipeline  job     build #  build id  type   name       attempt
e467775c-ab6e-413d-5823-45fc84e2a3fd  demo    yeeehaa   my-job  5        8         task   say-hello  n/a
e5908c49-0ca2-4482-558e-99da76c44a79  demo    none      none    none     none      check  none       n/a
Enter fullscreen mode Exit fullscreen mode

Resources:

If you feel like exploring more, check out their website and my other blogs for more concourse content:

Thank You

Let me know what you think. If you liked my content, feel free to visit me at ruan.dev or follow me on twitter at @ruanbekker

Top comments (1)

Collapse
 
vjvijay868 profile image
vijay •

can u please help me how to setup concourse CI on windows like linux without docker and clusters

Read next

oliverbennet profile image

I Started Learning Docker a Year Ago, Now I make my Own Containers.

Oliver Bennet -

judith677 profile image

#87 — Merge Data of The Same Group

Judith-Excel-Sharing -

luqmanbello profile image

Building Production-Grade ECS Anywhere Infrastructure with Custom Capacity Providers

Luqman Bello -

karthickdkk profile image

Dangerous Linux Configurations You Must Avoid for Secure Systems (Deep Dive)

karthick-dkk -