Error: cannot open display: :0 for Selenium tests

Question

Firstly I was getting the following error:

org.openqa.selenium.firefox.NotConnectedException: Unable to connect to host 127.0.0.1 on port 7055 after 45000 ms. Fi         


        

Answer 1

The best approach to solve this problem is making changes to the jenkins start script.

The solution that works on Ubuntu for me correctly is as follows:

1.Open Jenkins shell script located at: /etc/init.d/jenkins.

2.Add the following lines as follows before PATH variable:

/usr/bin/X :0 vt7 -ac
export DISPLAY=:0
xhost +

Answer 2

You can download the Jenkins xvnc plugin and make that plugin start(and export) a virtual display for selenium to use. The jenkins user may not have access to the :0 display.