Prometheus Installation

I am using linux ubuntu machine for this installation. I spin up linux ubuntu machine in AWS cloud, and it is up and running. I have also connected EC2 instance using iterm terminal in my Mac machine.

Step 1

Go to the website "https://prometheus.io/download/" and find the latest version of prometheus tar file. Copy the link for that tar file.

Step 2

Run the command "wget " in the terminal to download the tar file.

wget https://github.com/prometheus/prometheus/releases/download/v2.54.1/prometheus-2.54.1.linux-amd64.tar.gz

Step 3

Untar the downloaded file using the command "tar -xvzf .

tar -xvzf prometheus-2.54.1.linux-amd64.tar.gz

Step 4

Navigate to prometheus directory (unzipped one)

Step 5

Start the prometheus executable file (This is nothing but prometheus server)

Step 6

Open the browser and enter prometheus server IP followed by port number 9090.

Stopping prometheus server

Now prometheus UI is not working.

Prometheus is up and running now. However, if I close the terminal where prometheus executable is running or my EC2 instance is down, then the prometheus also stops. Hence, this is not the ideal way to run the prometheus.

The ideal way of running prometheus is to install and run as a service.

To do so, we need to follow below steps

Step 1 - Update the system packages

Run the command

sudo apt update

Step 2 - Create a system user for prometheus

System username is prometheus. Before doing it, we need to ensure prometheus user is not created yet.

To do so, run the command cat /etc/passwd | grep -i prometheus If it returns value, it means prometheus user is already available in the system.

As the above command returns nothing, we can create system user now. To create the user, run the below commands

sudo groupadd --system prometheus
sudo useradd -s /sbin/nologin --system -g prometheus prometheus

Let us ensure the user prometheus is created.

cat /etc/passwd | grep -i prometheus

Step 3 - Create Directories for Prometheus

To store configuration files and libraries for Prometheus, you need to create a few directories. The directories will be located in the /etc and the /var/lib directory respectively. Use the commands below to create the directories:

sudo mkdir /etc/prometheus
sudo mkdir /var/lib/prometheus

Step 4 - Move the Binary Files & Set Owner

Navigate to the prometheus directory. You need to move some binary files (prometheus and promtool) and change the ownership of the files to the "prometheus" user and group. You can do this with the following commands:

sudo mv prometheus /usr/local/bin
sudo mv promtool /usr/local/bin

# set the owner 
sudo chown prometheus:prometheus /usr/local/bin/prometheus
sudo chown prometheus:prometheus /usr/local/bin/promtool

Step 5 - Move the Configuration Files & Set Owner

Next, move the configuration files and set their ownership so that Prometheus can access them. To do this, run the following commands:

sudo mv consoles /etc/prometheus
sudo mv console_libraries /etc/prometheus
sudo mv prometheus.yml /etc/prometheus

# set the owner 
sudo chown prometheus:prometheus /etc/prometheus
sudo chown -R prometheus:prometheus /etc/prometheus/consoles
sudo chown -R prometheus:prometheus /etc/prometheus/console_libraries
sudo chown -R prometheus:prometheus /var/lib/prometheus

The prometheus.yml file (/etc/prometheus/prometheus.yml) is the main Prometheus configuration file. It includes settings for targets to be monitored, data scraping frequency, data processing, and storage.

Step 6 - Create Prometheus Systemd Service

Now, you need to create a system service file for Prometheus. Create and open a prometheus.service file with the vi text editor using:

vi /etc/systemd/system/prometheus.service

Content of the file is

[Unit]
Description=Prometheus
Wants=network-online.target
After=network-online.target

[Service]
User=prometheus
Group=prometheus
Type=simple
ExecStart=/usr/local/bin/prometheus \
    --config.file /etc/prometheus/prometheus.yml \
    --storage.tsdb.path /var/lib/prometheus/ \
    --web.console.templates=/etc/prometheus/consoles \
    --web.console.libraries=/etc/prometheus/console_libraries

[Install]
WantedBy=multi-user.target

Step 7 - Reload Systemd

You need to reload the system configuration files after saving the prometheus.service file so that changes made are recognized by the system. Reload the system configuration files using the following:

sudo systemctl daemon-reload

Step 8 - Start Prometheus Service

Next, you want to enable and start your Prometheus service. Do this using the following commands:

sudo systemctl enable prometheus
sudo systemctl start prometheus

Step 9 - Check Prometheus Status

After starting the Prometheus service, you may confirm that it is running or if you have encountered errors using:

sudo systemctl status prometheus

Step 10 - Update firewall rules Prometheus runs on port 9090 by default, so you need to allow port 9090 on your firewall, Do that using the command:

sudo ufw allow 9090/tcp

With Prometheus running successfully, you can access it via your web browser using :9090

Run the query in prometheus UI.