Prometheus is an open-source systems monitoring and alerting toolkit originally built at SoundCloud. Since its inception in 2012, many companies and organizations have adopted Prometheus, and the project has a very active developer and user community. It is now a standalone open source project and maintained independently of any company.
Features
Prometheus’s main features are:
- a multi-dimensional data model with time series data identified by metric name and key/value pairs
- PromQL, a flexible query language to leverage this dimensionality
- no reliance on distributed storage; single server nodes are autonomous
- time series collection happens via a pull model over HTTP
- pushing time series is supported via an intermediary gateway
- targets are discovered via service discovery or static configuration
- multiple modes of graphing and dashboarding support
Basic Setup
As part of a basic setup we’re going to setup Prometheus and Node Exporter. Node Exporter exposes a wide variety of hardware- and kernel-related metrics.
To install Prometheus and Node Exporter, run the below command.
sudo apt -y install prometheus prometheus-node-exporter
Once they are installed, make sure to have a look at the configuration file.
root@sethlahaul:~# cat /etc/prometheus/prometheus.yml
# Sample config for Prometheus.
global:
scrape_interval: 15s # Set the scrape interval to every 15 seconds. Default is every 1 minute.
evaluation_interval: 15s # Evaluate rules every 15 seconds. The default is every 1 minute.
# scrape_timeout is set to the global default (10s).
# Attach these labels to any time series or alerts when communicating with
# external systems (federation, remote storage, Alertmanager).
external_labels:
monitor: 'example'
# Alertmanager configuration
alerting:
alertmanagers:
- static_configs:
- targets: ['localhost:9093']
# Load rules once and periodically evaluate them according to the global 'evaluation_interval'.
rule_files:
# - "first_rules.yml"
# - "second_rules.yml"
# A scrape configuration containing exactly one endpoint to scrape:
# Here it's Prometheus itself.
scrape_configs:
# The job name is added as a label `job=<job_name>` to any timeseries scraped from this config.
- job_name: 'prometheus'
# Override the global default and scrape targets from this job every 5 seconds.
scrape_interval: 5s
scrape_timeout: 5s
# metrics_path defaults to '/metrics'
# scheme defaults to 'http'.
static_configs:
- targets: ['localhost:9090']
- job_name: node
# If prometheus-node-exporter is installed, grab stats about the local
# machine by default.
static_configs:
- targets: ['localhost:9100']
Once the above steps are completed, enable the Prometheus and Node Exporter services using the below command.
systemctl enable prometheus prometheus-node-exporter
Once the services are started, go to http://localhost:9090/graph where you will see the Prometheus home screen.
To check if you have metric data present, you can select node_procs_running. You can then view the metrics in graphical format.
That’s it for this tutorial. Stay tuned for more.
