Synthetic website monitoring with Selenium and Docker.



Synthetic website monitoring with Selenium and Docker.

check_selenium_docker is a Nagios based plugin that spins up a Docker container, executes the test and, once the test is finished and the result has been reported back to the monitoring solution, removes the Docker container.



Install Selenium IDE for Chrome (

Record your test.

Export the test and copy the .side file to the server that will run the docker image.

A Docker container will execute the test and report the test results back to the monitoring system.


System requirements

The following prerequisites must be installed on the server that will execute the plugin.

  • Python 3 with the docker module
  • docker-ce

ITRS OP5 Monitor example

# Install docker-ce
yum install -y yum-utils \
  device-mapper-persistent-data \

yum-config-manager \
    --add-repo \

yum install docker-ce

# Add user 'monitor' to group 'docker'
usermod -aG docker monitor

# Start and enable docker
systemctl start docker && systemctl enable docker

# Install the docker Python 3 module
pip-3 install docker

# (Optional) Add versionlock to docker-ce
yum install yum-plugin-versionlock
yum versionlock docker-ce

# (Optional) Remove versionlock from docker-ce
yum versionlock clear

Docker image

Build the Docker image:

git clone
cd check_selenium_docker/dockerimage/
docker build . --tag opsdis/selenium-chrome-node-with-side-runner


Copy the plugin to the plugin directory and make it executable:

cp /opt/plugins/custom/
chmod +x /opt/plugins/custom/

Add a new check_command to Monitor:

$USER1$/custom/ $ARG1$

Add new test scenarios

Create a new main directory (/opt/plugins/custom/selenium) in the main directory create a new directory preferably named as the URL used in the test (/opt/plugins/custom/selenium/

mkdir /opt/plugins/custom/selenium
mkdir /opt/plugins/custom/selenium/

Create two subdirectories, out and sides:

mkdir /opt/plugins/custom/selenium/{out,sides}

Add the side-file to the sides subdirectory and modify the permissions:

chmod 777 /opt/plugins/custom/selenium/
chmod 755 /opt/plugins/custom/selenium/

The directory structure should look like this:

│   ├── out
│   └── sides
│       └──

Execute the plugin

/opt/plugins/custom/ /opt/plugins/custom/selenium/
OK: Passed 1 of 1 tests. | 'passed'=1;;;; 'failed'=0;;;; 'exec_time'=6s;;;;


check_selenium_docker is licensed under GPL version 3.