Skip to content

Instantly share code, notes, and snippets.

@ostinelli
Last active February 14, 2023 07:12
Show Gist options
  • Save ostinelli/b77c20d91e4e33507813 to your computer and use it in GitHub Desktop.
Save ostinelli/b77c20d91e4e33507813 to your computer and use it in GitHub Desktop.
Setup Jenkins CI on Ubuntu.

Jenkins CI

Instructions on how to setup a secured Jenkins CI.

Install Jenkins

$ wget -q -O - https://jenkins-ci.org/debian/jenkins-ci.org.key | sudo apt-key add -
$ sudo sh -c 'echo deb http://pkg.jenkins-ci.org/debian binary/ > /etc/apt/sources.list$ .d/jenkins.list'
$ sudo apt-get update
$ sudo apt-get install jenkins
$ sudo service jenkins start

Install Git

$ sudo apt-get install git

Update all plugins

Once you can access your Jenkins console, goto Manage Jenkins -> Manage Plugins from the home screen.

Sometimes when you install, you will notice that the list of available plugins is empty. If that is the case, from Advanced tab on the Manage Plugins page, click on Check now (button available in the bottom right of the page) to forcefully check for new updates. Once that is done, you should see the list of plugins.

In the Updates tab, check all and click download and install after restart. Once downloads are finished , check Restart Jenkins when installation is complete and no jobs are running.

Install plugins

Open the Available tab and find the plugin entitled:

  • Git Plugin
  • Github plugin
  • Rake plugin
  • RVM plugin
  • Green balls

Download and restart Jenkins.

Configure Git

Login to your box and switch to the Jenkins user. The installation process doesn't create a password so you'll need to have root/sudo permissions to do this. Run the command:

$ sudo su - jenkins

The - specifies a login shell, and will switch you to jenkins' home directory (for me this was /var/lib/jenkins).

Create a .ssh directory in the Jenkins home directory.

$ mkdir ~/.ssh

Create the public private key pair. The most important thing is not to set a password, otherwise the jenkins user will not be able to connect to the git repo in an automated way.

$ cd ~/.ssh
$ ssh-keygen -t rsa -C "jenkins@CI"

Start the ssh-agent in the background and add the key:

eval "$(ssh-agent -s)"
ssh-add ~/.ssh/id_rsa

Display your newly creted public key:

$ cat id_rsa.pub

Copy the output and add it to your Git repo.

Set a git user and email address:

$ git config --global user.email "cloud+jenkins@example.com"
$ git config --global user.name "jenkins"

Connect to the Git repo. This is a one time step which will dismiss that 'Are you sure you want to connect' ssh message, again jenkins won't be able to deal with this. Just run:

$ ssh -T git@github.com

Install Ruby & Rails

Dependencies:

$ sudo apt-get install autoconf bison build-essential libssl-dev libyaml-dev libreadline6 libreadline6-dev zlib1g zlib1g-dev

RVM:

$ gpg --keyserver hkp://keys.gnupg.net --recv-keys D39DC0E3
$ \curl -sSL https://get.rvm.io | bash -s stable --ruby
$ source /var/lib/jenkins/.rvm/scripts/rvm

Ruby (match the version of the project):

$ rvm install 2.1.4
$ rvm use 2.1.4 --default

Install PostgreSQL

$ sudo apt-get install postgresql postgresql-contrib postgresql-dev
$ sudo -u postgres psql -c "ALTER USER postgres PASSWORD '';"
$ sudo vim /etc/postgresql/9.3/main/pg_hba.conf

change:

local	all	postgres	peer

to:

# "local" is for Unix domain socket connections only
local   all	all		trust
# IPv4 local connections:
host    all	all		127.0.0.1/32            trust
# IPv6 local connections:
host    all	all		::1/128                 trust

Reload conf:

$ psql -U postgres
postgres=# select pg_reload_conf();

$ sudo service postgresql restart

Install other gem dependencies

$ sudo apt-get install libcurl3-dev libpq-dev

Try project

$ cd ~/jobs/myproject/workspace
$ bundle

Create Job

Next, configure our Rails project.

From the home page, click on New Item, then select Build a free-style software project and click OK.

Fill in the Project Name and GitHub project fields.

Under Source Code Management, select Git and fill in the repo url. Add SSH keys here.

Check the Run the build in a RVM-managed environment box, and enter in Implementation:

ruby-2.1.4@myproject

Poll SCM with a schedule of:

H/5 * * * *

Under Add build step, select Execute shell, and enter:

bundle install
bundle exec rake db:setup
bundle exec rake ci:all

Add the "Publish JUnit test result report" post-build step in the job configuration. Enter spec/reports/*.xml in the Test report XMLs field (adjust this to suit which tests you are running).

Configure security

Navigate back to Manage Jenkins and select Configure Global Security. On this screen, check Enable Security, then Jenkins' own user database under Security Realm. After that, select Project-based Matrix Authorization Strategy under Authorization.

From there, add admin and localmonitor users, checking all permissions for admin and only Overall Read and JOB read forlocalmonitor. Save the changes.

Saving the security configuration will log you out of Jenkins. We've only created permissions at this point, so create the admin user account by clicking Create an account. Create the localmonitor user by navigating to Manage Users under Manager Jenkins.

Don't forget to uncheck Allow users to sign up under Configure Global Security.

Add SSL with Nginx

Install Nginx:

$ sudo apt-get install nginx

If you want to sign the server with self-generated credentials, create ssl keys and cert:

$ sudo mkdir ssl
$ cd ssl
$ sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/nginx/ssl/server.key -out /etc/nginx/ssl/server.crt

Otherwise get the server.crt and the server.key from your authority.

Configure:

$ sudo rm /etc/nginx/sites-enabled/default
$ sudo rm /etc/nginx/nginx.conf
$ sudo vim /etc/nginx/nginx.conf


user www-data;
worker_processes 4;
pid /run/nginx.pid;

events {
	worker_connections 768;
	# multi_accept on;
}

http {
	upstream jenkins {
	  server 127.0.0.1:8080 fail_timeout=0;
	}

	server {
	  listen 80;
	  return 301 https://$host$request_uri;
	}

	server {
	  listen 443;
	  server_name jenkins;

	  ssl on;
	  ssl_certificate /etc/nginx/ssl/server.crt;
	  ssl_certificate_key /etc/nginx/ssl/server.key;

	  location / {
	    proxy_set_header        Host $host;
	    proxy_set_header        X-Real-IP $remote_addr;
	    proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;
	    proxy_set_header        X-Forwarded-Proto $scheme;
	    proxy_redirect http:// https://;
	    proxy_pass              http://jenkins;
	  }
	}
}

Save and restart nginx:

$ sudo service nginx restart
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment