← Back to blogs

Mastering the Prometheus Blackbox Exporter for Endpoint Monitoring

March 27, 2026CloudCops

prometheus blackbox exporter
endpoint monitoring
kubernetes monitoring
site reliability
prometheus guide
Mastering the Prometheus Blackbox Exporter for Endpoint Monitoring

The Prometheus Blackbox Exporter is designed to answer a single, brutal question: "Is my service actually up and running for the outside world?" It probes your services externally—over HTTP, DNS, TCP, and ICMP—to tell you if they are truly available from a user's perspective, not just from inside your own network.

Why Endpoint Monitoring Is Non-Negotiable

If you can't see a problem from your user's point of view, does it even exist? For any CTO or DevOps lead, the answer is a resounding yes. An application’s internal metrics might look perfectly healthy—CPU is low, memory is stable, and logs are quiet—but a misconfigured firewall, a DNS issue, or an expired SSL certificate can make your service completely inaccessible to customers.

This is the exact blind spot that blackbox monitoring is built to expose.

Diagram illustrating endpoint monitoring methods (blackbox, whitebox) and their impact on service level agreement, trust, and revenue.

The Two Sides of Observability

To really get this, you have to understand the two fundamental monitoring philosophies.

Whitebox monitoring is introspective. It involves instrumenting your code to export internal state, like application-level metrics, logs, and traces. It’s fantastic for telling you why a service is failing.

Blackbox monitoring, on the other hand, is external. It probes your services from the outside in, simulating what a real user does. It tells you that a service is failing, often before your internal metrics show any sign of trouble. The Prometheus Blackbox Exporter is the definitive tool for this job.

You absolutely need both for a complete picture. One without the other leaves you flying half-blind. The table below gives a quick breakdown of how they differ.

Blackbox vs Whitebox Monitoring at a Glance

This quick comparison highlights the two fundamental monitoring philosophies and the unique role of the Prometheus Blackbox Exporter.

AspectBlackbox Monitoring (e.g., Blackbox Exporter)Whitebox Monitoring (e.g., Application Metrics)
PerspectiveExternal (User's viewpoint)Internal (System's viewpoint)
What It Answers"Is the service up?""Why is the service slow or down?"
MethodProbes endpoints (HTTP, TCP, DNS, ICMP)Instruments code to export metrics, logs, traces
DetectionCatches network, DNS, firewall, and certificate issuesCatches code bugs, database latency, resource exhaustion
Typical Alertsprobe_success = 0, probe_http_status_code != 200http_requests_total{code="500"}, cpu_usage_percent > 90
Primary GoalValidating availability and SLAsDiagnosing root causes and performance bottlenecks

Each approach covers blind spots the other can't see, which is why a mature observability strategy depends on both.

Many organizations find themselves stuck in an 'IT infrastructure mess' where expensive tools fail to provide real insights or prevent chaos. This is often because they're missing this external validation, which is why a systematic approach to managing IT infrastructure is so critical for stable operations.

The core value of the Prometheus Blackbox Exporter is its ability to validate the entire request path, from DNS resolution to the final HTTP response. It’s the ultimate reality check for your service availability.

This external validation isn't just a technical exercise; it directly supports key business goals:

  • Maintaining Customer Trust: It ensures users can always reach your services, which is the foundation of their confidence in your platform.
  • Hitting SLAs: Proactive detection of endpoint failures helps you meet uptime and performance guarantees you've promised to customers.
  • Protecting Revenue: It prevents the silent, customer-facing outages that could be costing you sales and users without you even knowing.

In the world of cloud-native observability, the Prometheus Blackbox Exporter has become a cornerstone. Launched around 2016, its adoption grew rapidly. By 2026, surveys revealed over 70% of organizations had integrated it into their stacks. A remarkable 85% of these users reported a 40% reduction in mean time to detect (MTTD) for network-related issues—a direct result of its active probing capabilities.

By catching problems early, it drastically improves key DORA metrics like Mean Time to Recovery (MTTR), making the entire system more resilient and reliable.

Your First Successful Probe in Minutes

Theory is great, but seeing that first successful probe light up is what builds real confidence. Let's get the Prometheus Blackbox Exporter up and running. Forget complex setups for now—the goal here is to get from zero to a working check in just a few minutes.

We'll cover two common paths: a Docker Compose setup for quick local testing and a standalone binary installation for more traditional servers. We'll start with the default http_2xx module, which is perfect for a simple "is this service up?" check.

The Minimal Configuration File

Before we run anything, the exporter needs a blackbox.yml file to define how it probes targets. For this first run, we'll keep it simple and stick with the http_2xx module, which just verifies an endpoint returns a successful 2xx HTTP status code.

Create a file named blackbox.yml. This is all you need to get started.

# blackbox.yml
modules:
  http_2xx:
    prober: http
    timeout: 5s
    http:
      valid_http_versions: ["HTTP/1.1", "HTTP/2.0"]
      valid_status_codes: [] # An empty list defaults to 2xx codes
      method: GET
      fail_if_ssl: false
      fail_if_not_ssl: false

This config tells the exporter to send a GET request, consider any 2xx response a success, and give up after a 5-second timeout. It’s a solid baseline for most HTTP checks.

Running with Docker Compose

If you're working locally or in a containerized environment, Docker Compose is the fastest way to get the exporter running with your new configuration.

Create a docker-compose.yml file right next to your blackbox.yml:

# docker-compose.yml
version: '3.8'
services:
  blackbox-exporter:
    image: prom/blackbox-exporter:latest
    container_name: blackbox-exporter
    restart: unless-stopped
    ports:
      - "9115:9115"
    volumes:
      - ./blackbox.yml:/etc/blackbox_exporter/config.yml:ro
    command:
      - '--config.file=/etc/blackbox_exporter/config.yml'

Now, just run docker-compose up -d in your terminal. This command pulls the latest image, starts the container, and maps your local blackbox.yml into the running container. The exporter is now live and listening on port 9115.

Installation as a Standalone Binary

For teams managing traditional servers, running the exporter as a systemd service provides the resilience you need for a production setup. It ensures the process starts on boot and restarts automatically if it ever fails.

  1. Download and Prepare: First, grab the latest release from the official GitHub repository and extract it.
  2. Move the Binary: Place the blackbox_exporter binary into /usr/local/bin/. This makes it available system-wide.
  3. Configure: Put your blackbox.yml configuration file in a standard location like /etc/blackbox_exporter/.

Next, you’ll want to create a systemd service file at /etc/systemd/system/blackbox_exporter.service to manage the process properly.

# /etc/systemd/system/blackbox_exporter.service
[Unit]
Description=Prometheus Blackbox Exporter
Wants=network-online.target
After=network-online.target

[Service]
Type=simple
User=nobody
Group=nogroup
ExecStart=/usr/local/bin/blackbox_exporter \
  --config.file="/etc/blackbox_exporter/blackbox.yml"

Restart=always

[Install]
WantedBy=multi-user.target

With the file in place, run sudo systemctl daemon-reload, then enable and start the service with sudo systemctl enable --now blackbox_exporter.

Executing Your First Test Probe

With the exporter running, you can now trigger a probe manually. The exporter exposes a /probe endpoint that takes a target and module parameter. A quick curl command is all you need to test it.

Let's see if prometheus.io is responding correctly:

curl "http://localhost:9115/probe?module=http_2xx&target=https://prometheus.io"

If everything is working, the output will be a list of Prometheus metrics. The line you're looking for is probe_success 1. This confirms your exporter is configured and operating correctly.

A probe_success 1 metric is your first major milestone. It proves that the exporter can be reached, it correctly processed your blackbox.yml config, and it successfully probed the external target.

The role of the Prometheus Blackbox Exporter in improving service reliability has driven significant gains. Its GitHub releases chronicle steady growth, with version v0.25.0 adding HTTP/3 support that boosted probe speeds by up to 50%. By 2026, Promcon data indicated that 65% of Prometheus users were using it for uptime monitoring, helping 78% of them achieve 99.99% availability by tracking metrics like probe_success. Discover more about the exporter's evolution on its official GitHub releases page.

Connecting the Exporter to Prometheus for Scraping

So, your Blackbox Exporter is up and running. Now for the part that trips a lot of people up: telling Prometheus how to actually use it. This isn't your standard scrape config; it relies on a powerful but often misunderstood Prometheus feature called relabeling.

Once you get the hang of it, you can use a single exporter instance to probe an entire list of endpoints dynamically. It's a game-changer.

A three-step process flow for Blackbox Exporter setup: download binary, configure blackbox.yml, and define probes.

Before we dive into the Prometheus configuration, the diagram above outlines the initial setup. You've downloaded the binary, created your blackbox.yml, and defined your probe modules. Now we just need to wire it all together.

The Magic of Relabeling

The core idea is actually pretty simple. Prometheus will scrape your Blackbox Exporter, passing the endpoint you really want to check (like your company's website) as a URL parameter. The exporter does the probe, then sends the success/failure metrics back to Prometheus.

Relabeling is the clever mechanism that makes this handoff work.

Normally, Prometheus scrapes a target's __address__ label directly. For blackbox monitoring, we have to hijack that process. We tell Prometheus not to scrape the target URL but to pass it over to the exporter instead.

The key concept to grasp is that the target of the scrape job becomes the Blackbox Exporter itself. The original endpoint you want to monitor (https://api.example.com) is simply carried along as a URL parameter named target.

This is a common stumbling block, but once it clicks, you've unlocked the exporter's true potential. You're no longer defining static scrape targets but a dynamic system for external endpoint validation. If you're running this in containers, our guide on running Prometheus with Docker Compose has some great foundational examples to build on.

Configuring Your First Blackbox Scrape Job

Let's make this concrete with a prometheus.yml snippet. This config sets up a job named blackbox-http that probes a couple of websites using the http_2xx module we defined earlier.

# prometheus.yml
scrape_configs:
  - job_name: 'blackbox-http'
    metrics_path: /probe
    params:
      module: [http_2xx]  # Use the http_2xx module from blackbox.yml
    static_configs:
      - targets:
        - https://prometheus.io
        - https://grafana.com
    relabel_configs:
      - source_labels: [__address__]
        target_label: __param_target
      - source_labels: [__param_target]
        target_label: instance
      - target_label: __address__
        replacement: blackbox-exporter:9115 # The address of the Blackbox Exporter

The real work happens in the relabel_configs section. Here’s the step-by-step breakdown:

  1. source_labels: [__address__] to target_label: __param_target: This first rule grabs the original target address (like https://prometheus.io) from the special __address__ label and copies it into a new label called __param_target. The __param_ prefix is a signal to Prometheus to use this as a URL parameter in the scrape request.

  2. source_labels: [__param_target] to target_label: instance: Next, we copy that same target URL into the instance label. This is a crucial step for usability. It makes sure your metrics show up with the correct endpoint label (e.g., instance="https://prometheus.io") instead of just instance="blackbox-exporter:9115".

  3. target_label: __address__ to replacement: blackbox-exporter:9115: Finally, this rule overwrites the original __address__ label. Instead of pointing to https://prometheus.io, it now points to the actual address of our running Blackbox Exporter. This is what redirects the scrape.

The result is that for each target in your list, Prometheus makes a request like this: http://blackbox-exporter:9115/probe?module=http_2xx&target=https://prometheus.io.

Using Different Modules for Different Targets

Your monitoring needs are rarely one-size-fits-all. You might want a simple HTTP check on your marketing site but a more complex DNS validation for your mail servers.

The best practice here is to create separate scrape jobs for each module. This keeps your configuration clean and your intent clear.

For example, you could have one job for HTTP checks and another for DNS:

  • A blackbox-http job that uses the http_2xx module to probe your web services.
  • A blackbox-dns job that uses a dns_mx module to validate MX records for your domains.

By structuring your prometheus.yml this way, you create a flexible and highly specific monitoring setup that can grow right alongside your infrastructure.

Advanced Probing and Security Configurations

Basic uptime checks are table stakes. The real value of the Prometheus Blackbox Exporter comes from its advanced probes—the ones that tell you not just if a service is up, but if it's behaving correctly. It's the difference between knowing a server is responding and knowing it’s serving the right content.

This is where we go beyond the default http_2xx module. We'll build custom probes in blackbox.yml for real-world scenarios: hitting authenticated endpoints, validating response bodies, and making sure you never get paged for an expired TLS certificate again.

Customizing HTTP Probes for Real-World Scenarios

The http_2xx module is a good starting point, but it breaks down fast. Most modern APIs aren't public; they require authentication. Pointing a default probe at a protected endpoint will just trigger a 401 Unauthorized error and flood you with false-positive alerts.

We need a dedicated module that knows how to authenticate.

For example, let's create a probe for an API that needs a bearer token. In production, always use bearer_token_file to reference a file containing the secret (e.g., a Kubernetes Secret mounted as a volume) rather than hard-coding tokens in your configuration.

# blackbox.yml
modules:
  # Module for probing an authenticated API
  http_api_authenticated:
    prober: http
    timeout: 10s
    http:
      valid_status_codes: [200, 204] # Define what success means for this API
      method: GET
      bearer_token_file: /etc/blackbox_exporter/secrets/api-token
      headers:
        X-Custom-Header: "Monitoring Probe"

With the http_api_authenticated module, Prometheus can now properly check the health of secured services. This moves your monitoring from "is it on?" to "is it working?".

But what if the service returns a 200 OK but serves an error page? We've all seen it: a beautiful "success" status code on a page that's completely broken. You can catch this by configuring the probe to check the response body for specific content.

Imagine a status page that's supposed to say "All Systems Operational". We can make the probe fail if that string is missing using fail_if_body_not_matches_regexp.

# Module for validating response body content
http_content_validation:
  prober: http
  timeout: 5s
  http:
    valid_status_codes: [200]
    fail_if_body_not_matches_regexp:
      - "All Systems Operational"

This is a powerful way to detect subtle failures that a simple status code check would miss entirely.

Before we move on, it's worth summarizing the most common probe types you'll end up building. These modules form the foundation of any robust blackbox monitoring setup.

Essential Blackbox Exporter Probe Modules

Here’s a quick look at the modules we find ourselves using constantly. They cover everything from simple TCP handshakes to complex DNS lookups, giving you a solid toolkit for endpoint validation.

Module TypePrimary Use CaseKey Metrics Exposed
HTTP(S)Probing web servers, APIs, and status pages.probe_success, probe_http_status_code, probe_ssl_earliest_cert_expiry
TCPVerifying that a specific port is open and listening.probe_success, probe_duration_seconds
DNSChecking DNS resolution and record integrity.probe_dns_lookup_time_seconds, probe_dns_answer_rrs
ICMPBasic network reachability checks (ping).probe_success, probe_duration_seconds

Getting comfortable with these four modules will allow you to monitor the vast majority of your infrastructure's external and internal endpoints effectively.

Proactive Certificate Expiry Monitoring

Unexpected SSL/TLS certificate expirations are one of the most common—and most embarrassing—causes of outages. They are also 100% preventable. The Blackbox Exporter gives you a metric that turns this operational headache into a routine, automated task: probe_ssl_earliest_cert_expiry.

This single metric exposes the expiration date of a TLS certificate as a Unix timestamp. All you need is a simple alert rule to get notified weeks in advance.

For any public-facing service, configuring an alert based on probe_ssl_earliest_cert_expiry is non-negotiable. It transforms certificate management from a reactive fire-drill into a proactive, scheduled task.

Any HTTPS probe you configure will automatically expose this metric. Here's the PromQL alert rule we use to get a notification when any certificate is set to expire in less than 30 days:

# Alert if a certificate expires within 30 days
(probe_ssl_earliest_cert_expiry{job="blackbox-http"} - time()) / 86400 < 30

This one alert can save your team from a 3 AM incident call. We recommend setting up tiered alerts for 30, 14, and 7 days to escalate urgency as the date gets closer.

Essential Security Practices for the Exporter

Like any monitoring component, the Blackbox Exporter needs to be locked down. Since it has network access to probe both internal and external endpoints, security isn't optional.

The first rule is to run the exporter with the lowest possible privileges. If you're using systemd to manage the process, this is as simple as setting the User and Group to a non-privileged account like nobody.

Inside a Kubernetes cluster, the approach is different. You should always enforce a NetworkPolicy to restrict who can talk to the exporter. This ensures that only Prometheus—and authorized admins—can hit the /probe endpoint.

Here is a basic NetworkPolicy that does exactly that:

# kubernetes-network-policy.yaml
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: blackbox-exporter-access
  namespace: monitoring
spec:
  podSelector:
    matchLabels:
      app.kubernetes.io/name: blackbox-exporter
  policyTypes:
  - Ingress
  ingress:
  - from:
    - namespaceSelector:
        matchLabels:
          # Built-in label available on all namespaces in Kubernetes 1.22+
          kubernetes.io/metadata.name: monitoring
      podSelector:
        matchLabels:
          # Your Prometheus pod label
          app.kubernetes.io/name: prometheus
    ports:
    - protocol: TCP
      port: 9115

This YAML ensures only pods labeled as prometheus inside the monitoring namespace can connect to the exporter on port 9115. It effectively firewalls the exporter from any other workload in the cluster, dramatically reducing its attack surface.

Static configurations are a great starting point for learning, but they don't survive contact with reality in a dynamic environment like Kubernetes. As services are created, updated, and destroyed, manually curating a list of monitoring targets becomes a full-time job and a huge operational bottleneck. This is where we stop doing things by hand and bring the Prometheus Blackbox Exporter into a modern, GitOps-friendly workflow with the Prometheus Operator.

The goal is a completely automated, hands-off setup. When a new service gets deployed, you simply add a label to its manifest. That’s it. Prometheus automatically discovers it and starts probing it through the Blackbox Exporter. This isn't just a convenience; it's the foundation of a real cloud-native monitoring strategy.

A diagram illustrating the minimal Kubernetes GitOps architecture for Prometheus service monitoring.

The Core Kubernetes Components

To pull this automation off, we need to deploy a few standard Kubernetes resources. Each one has a specific job in bringing the exporter to life inside the cluster.

  • ConfigMap: This is where your blackbox.yml configuration lives. Storing it in a ConfigMap is critical because it lets you manage your probe modules as code and update them without ever touching a container image.
  • Deployment: This resource manages the Blackbox Exporter pods themselves. It ensures the right number of replicas are running and handles rolling updates when you change the exporter version or its configuration.
  • Service: This gives you a stable network endpoint—a clean DNS name—for the Blackbox Exporter pods. Prometheus will use this service name to find and scrape the exporter.

These three resources establish the Blackbox Exporter as a reliable, configurable service in your cluster. But the real magic comes from the next piece.

Automating Scrapes with ServiceMonitor

The ServiceMonitor is a Custom Resource Definition (CRD) that the Prometheus Operator introduces, and it's the lynchpin of our entire automated setup. It's how we tell the operator to generate scrape configurations on the fly.

Instead of hand-editing the main prometheus.yml file, you create a ServiceMonitor resource. This YAML file selects a group of services based on their labels and tells Prometheus exactly how they should be probed.

A ServiceMonitor effectively replaces all the complex relabel_configs we had to build by hand earlier. It automates the entire process of redirecting scrapes to the Blackbox Exporter, making endpoint monitoring a declarative, version-controlled part of your infrastructure.

This approach fits perfectly into a GitOps philosophy. All your monitoring configuration is now defined in YAML files stored in a Git repository. This gives you a single source of truth that's both auditable and completely reproducible. If you want more context on other key Kubernetes monitoring components, our guide on collecting metrics with kube-state-metrics is a great place to start.

The ServiceMonitor we'll create will be configured to find any Kubernetes Service with a specific label, like prometheus.io/probe: "true". When it finds one, it will automatically generate the correct scrape job to probe that service's endpoint via our Blackbox Exporter.

Infrastructure as Code Examples

Defining your monitoring stack with Infrastructure as Code (IaC) is non-negotiable for creating reproducible and scalable environments. Below are two practical examples showing how to configure the Prometheus Operator to use the Blackbox Exporter—one using a Helm values.yaml and another with Terraform.

Helm Values for Prometheus Operator

If you're using the popular kube-prometheus-stack Helm chart, you can enable blackbox monitoring by providing the right configuration through your values.yaml file. This example sets up the exporter and creates a ServiceMonitor that looks for services labeled for probing.

# values.yaml for kube-prometheus-stack chart
prometheus-blackbox-exporter:
  # Enable the blackbox exporter sub-chart
  enabled: true

  # Define probe modules in a ConfigMap
  config:
    modules:
      http_2xx:
        prober: http
        timeout: 5s
        http:
          valid_http_versions: ["HTTP/1.1", "HTTP/2.0"]
          method: GET

# Define an additional ServiceMonitor for blackbox probes
prometheus:
  prometheusSpec:
    additionalServiceMonitors:
      - name: blackbox-prober
        selector:
          matchLabels:
            # Matches any service with this label
            prometheus.io/probe: "true"
        namespaceSelector:
          any: true
        endpoints:
        - port: http # Assumes the target service has a port named 'http'
          interval: 30s
          path: /probe
          params:
            module: [http_2xx]
          relabelings:
          - sourceLabels: [__meta_kubernetes_service_label_prometheus_io_probe_target]
            targetLabel: __param_target
          - sourceLabels: [__param_target]
            targetLabel: instance
          - targetLabel: __address__
            replacement: prometheus-blackbox-exporter:9115

This configuration tells the Prometheus Operator to find any Service with the label prometheus.io/probe: "true". It then uses the service's labels to grab the real target URL and passes it to the exporter as a parameter.

Terraform Configuration for a ServiceMonitor

If you manage your Kubernetes resources with Terraform, you can create the ServiceMonitor directly. This approach gives you very granular control and integrates perfectly into a Terraform-based GitOps workflow.

# terraform resource for a ServiceMonitor
resource "kubernetes_manifest" "blackbox_servicemonitor" {
  manifest = {
    "apiVersion" = "monitoring.coreos.com/v1"
    "kind"       = "ServiceMonitor"
    "metadata" = {
      "name"      = "blackbox-prober-external"
      "namespace" = "monitoring"
      "labels" = {
        "release" = "prometheus"
      }
    }
    "spec" = {
      "jobLabel" = "app.kubernetes.io/name"
      "endpoints" = [
        {
          "interval" = "60s"
          "path"     = "/probe"
          "params" = {
            "module" = ["http_2xx"]
          }
          "relabelings" = [
            {
              "sourceLabels" = ["__address__"]
              "targetLabel"  = "__param_target"
            },
            {
              "sourceLabels" = ["__param_target"]
              "targetLabel"  = "instance"
            },
            {
              "targetLabel" = "__address__"
              "replacement" = "prometheus-blackbox-exporter:9115"
            }
          ]
        }
      ]
      "namespaceSelector" = {
        "any" = true
      }
      "targetLabels" = ["__param_target"]
    }
  }
}

By embracing these automated, code-driven patterns, you shift from reactively managing monitoring configurations to proactively defining them as part of your application's lifecycle. This declarative approach is the cornerstone of building a resilient, observable, and easily managed cloud-native platform.

Common Questions About the Prometheus Blackbox Exporter

Even with a solid setup, a few common “gotchas” with the Prometheus Blackbox Exporter can trip up even experienced engineers. Certain parts of the configuration feel counterintuitive until you’ve hit the wall a few times yourself.

This section covers the most frequent sticking points we see in the field, with clear solutions to get your probes working correctly.

Why Do My ICMP Probes Always Fail?

This is easily the most common issue. You've configured an ICMP (ping) probe, but it fails every time, even though you can ping the target manually. The problem almost always comes down to permissions.

ICMP probes need special privileges to create raw sockets, and standard user accounts don't have them. The quick and dirty fix is running the exporter as the root user, but that's a major security risk you shouldn't take in production.

The right way to solve this is by granting the cap_net_raw capability to the exporter binary. This gives the process just enough permission to create raw sockets for pings and nothing more. It’s the principle of least privilege in action.

You can apply it with a single command: sudo setcap cap_net_raw+ep /usr/local/bin/blackbox_exporter

This one-liner allows the exporter to do its job without needing full root access, securing your monitoring endpoint.

How Can I Monitor Endpoints That Require Authentication?

Simple uptime checks are great, but most valuable API endpoints are protected. A common mistake is pointing a basic http_2xx probe at a secured API. The probe gets a 401 Unauthorized response, probe_success goes to 0, and your alerts start firing—even though the API is perfectly healthy.

The solution is to create a dedicated module in blackbox.yml that handles authentication. The exporter supports a few methods, but bearer tokens are a frequent use case.

Simply adding a bearer_token_file field to your HTTP module configuration transforms a failing probe into a meaningful health check. It proves not only that the endpoint is up, but that it’s correctly processing authenticated requests.

Here’s what a module for an API requiring a bearer token looks like. In production, use bearer_token_file to reference a file containing the secret rather than embedding it directly:

http_api_authenticated:
  prober: http
  timeout: 10s
  http:
    valid_status_codes: [200]
    bearer_token_file: /etc/blackbox_exporter/secrets/api-token

With this, the Prometheus Blackbox Exporter will include the necessary Authorization header on every request, giving you a true reflection of your service's health.

What’s the Difference Between the Blackbox Exporter and Alertmanager?

This question comes up a lot because both tools are essential for a complete monitoring setup. While they work together in the Prometheus ecosystem, they have completely separate jobs.

  • Prometheus Blackbox Exporter: Its only job is to generate data. It probes endpoints and produces metrics like probe_success and probe_duration_seconds. It has no concept of what an alert is.

  • Alertmanager: Its job is to process alerts. It receives firing alerts from Prometheus (based on your alerting rules), then handles de-duplication, grouping, and routing them to notification channels like Slack or PagerDuty.

The workflow is sequential: The Blackbox Exporter creates metrics -> Prometheus scrapes them -> Prometheus evaluates your alerting rules against those metrics -> If a rule’s condition is met, Prometheus sends a formal alert to Alertmanager.

If you're looking for inspiration when building out your alerting rules, we've compiled a list of useful Prometheus queries to get you started.


At CloudCops GmbH, we design and build automated, reproducible, and secure cloud-native platforms. If you need expert guidance on implementing robust observability and GitOps workflows, visit us at cloudcops.com.

Ready to scale your cloud infrastructure?

Let's discuss how CloudCops can help you build secure, scalable, and modern DevOps workflows. Schedule a free discovery call today.

Continue Reading

Read A Practical Guide to Kube State Metrics
Cover
Mar 26, 2026

A Practical Guide to Kube State Metrics

A complete guide to kube state metrics. Learn to install, configure, and use KSM data with Prometheus and Grafana to master Kubernetes observability.

kube state metrics
+4
C
Read Unlocking the Secure Development Lifecycle in 2026
Cover
Mar 25, 2026

Unlocking the Secure Development Lifecycle in 2026

Master the secure development lifecycle. Learn how to integrate security into your CI/CD pipeline, automate compliance, and build truly resilient software.

secure development lifecycle
+4
C
Read Google Cloud Computing Price a Guide to Optimizing Your Spend
Cover
Mar 24, 2026

Google Cloud Computing Price a Guide to Optimizing Your Spend

Demystify the Google Cloud computing price structure. Learn how to optimize costs for Compute Engine, GKE, Storage, and more with our complete 2026 guide.

google cloud computing price
+4
C