Alertmanager Installation

In this lesson you’ll learn how to download and install Alertmanager, start it, verify it’s running, and configure Prometheus to send alerts to it.

1. Download and extract Alertmanager

On the machine that will run Alertmanager, download the appropriate tarball from the Prometheus downloads page and extract it. Replace <ALERTMANAGER_TARBALL_URL> with the URL you copied for your platform.

# Download the tarball (replace the URL with the one you copied)
wget <ALERTMANAGER_TARBALL_URL>

# Extract the downloaded tarball
tar -xzf alertmanager-*.tar.gz

# Change into the extracted directory and inspect files
cd alertmanager-*/
ls -l

Typical contents of the extracted directory:

File / Directory	Purpose
`alertmanager`	The Alertmanager binary (start the server with this)
`amtool`	CLI utility to query and validate Alertmanager (`amtool` is useful for quick checks)
`alertmanager.yml`	Default configuration file for Alertmanager
`data/`	Stores notification and cluster state data

2. Start Alertmanager

From inside the extracted directory you can start Alertmanager directly:

./alertmanager

When Alertmanager starts successfully you should see logs similar to:

ts=2022-10-04T20:57:44.014Z caller=cluster.go:680 level=info component=cluster msg="Waiting for gossip to settle..." interval=2s
ts=2022-10-04T20:57:44.065Z caller=coordinator.go:113 level=info component=configuration msg="Loading configuration file" file=alertmanager.yml
ts=2022-10-04T20:57:44.065Z caller=coordinator.go:126 level=info component=configuration msg="Completed loading of configuration file" file=alertmanager.yml
ts=2022-10-04T20:57:44.068Z caller=main.go:535 level=info msg="Listening address=:9093"
ts=2022-10-04T20:57:44.068Z caller=tls_config.go:195 level=info msg="TLS is disabled." http2=false
ts=2022-10-04T20:57:46.014Z caller=cluster.go:705 level=info component=cluster msg="gossip not settled" polls=0 before=0 now=1 elapsed=2.000258318s
ts=2022-10-04T20:57:54.017Z caller=cluster.go:697 level=info component=cluster msg="gossip settled; proceeding" elapsed=10.002673562s

By default Alertmanager listens on port 9093. Open a browser to http://localhost:9093 (or http://<server-ip>:9093) to access the web UI.

A screenshot of the Alertmanager web UI showing the Alerts page with a filter box and controls for silencing alerts. The page displays a highlighted message: "No alert groups found."

3. Configure Prometheus to send alerts to Alertmanager

Tell Prometheus where your Alertmanager instances are by adding an alerting.alertmanagers section to prometheus.yml. Below is a minimal example showing a global block, the alerting configuration, and a sample rule file reference:

global:
  scrape_interval: 15s
  evaluation_interval: 15s

alerting:
  alertmanagers:
    - static_configs:
        - targets:
            - alertmanager1:9093
            - alertmanager2:9093

rule_files:
  - "rules.yml"

scrape_configs:
  # your scrape jobs here

Replace alertmanager1:9093 and alertmanager2:9093 with the hostnames or IPs (and ports) of your Alertmanager instances. Prometheus will push alerts to all listed targets.

Tips and troubleshooting

Alertmanager reads alertmanager.yml from the current working directory by default. To use a different config path start it with --config.file=/path/to/alertmanager.yml. Use amtool for quick CLI checks and validations — see the docs for amtool (e.g., ./amtool check-config alertmanager.yml) for examples: https://prometheus.io/docs/alerting/latest/alertmanager/#amtool

If Alertmanager is running on a remote host, ensure port 9093 is reachable from your Prometheus server (open firewalls, allow security group rules, and adjust SELinux if applicable). If you run multiple Alertmanager replicas, read the clustering docs to configure clustering and persistent storage correctly.

Additional resources

Prometheus Alerting: https://prometheus.io/docs/alerting/latest/
Alertmanager docs and configuration examples: https://prometheus.io/docs/alerting/latest/alertmanager/

That’s all — download and extract Alertmanager, start it, confirm the UI is reachable, and configure the alerting.alertmanagers section in Prometheus to forward alerts.

Introduction

Observability Fundamentals

Prometheus Fundamentals

PromQL

Dashboarding & Visualization

Application Instrumentation

Service Discovery

Push Gateway

Alerting

Monitoring Kubernetes

Conclusion

Scaling & Long Term Storage

Alertmanager Installation

1. Download and extract Alertmanager

2. Start Alertmanager

3. Configure Prometheus to send alerts to Alertmanager

Tips and troubleshooting

Additional resources

Watch Video

​1. Download and extract Alertmanager

​2. Start Alertmanager

​3. Configure Prometheus to send alerts to Alertmanager

​Tips and troubleshooting

​Additional resources

Watch Video

1. Download and extract Alertmanager

2. Start Alertmanager

3. Configure Prometheus to send alerts to Alertmanager

Tips and troubleshooting

Additional resources