Prometheus Health Check

To add Prometheus, you'll need the REST API endpoint of your Prometheus server and basic authentication headers.

To add a Prometheus Health Check:

1. Open the Health Checks page in the Gremlin web app and click + Health Check.
2. If Prometheus is already authenticated, select it from the Observability Tool drop-down and skip the following steps. Otherwise:
   
   1. In the Gremlin web app, navigate to Configurations → Health Checks → + Health Check.
   2. In the Authenticate tab, click on the Observability Tool drop-down and select Prometheus.
   3. Enter the URL for your Prometheus instance in the Prometheus URL box.
   4. Under Is this observability tool behind a firewall or on-prem?, choose:
      
      1. No if your instance is cloud-hosted and accessible over the Internet.
      2. Yes if your instance is self-hosted or behind a firewall.
   5. If your instance requires authentication, expand Authentication and enter your username and password.
   6. Click Next to save your settings.
3. Enter a Health Check Name to identify this check within Gremlin.
   
4. Choose how you want to define the monitor:
   1. If you don’t have the URL of the alert rule you want to use, but you know the name or tag(s), select Search Prometheus rules by names or tags. Enter a rule name or tag (such as “request rate” or “error_rate”), click Search, and select the desired alert rule from the list. Gremlin returns the first 100 results matching your query.
   2. If you already know the URL, select Provide Prometheus Alert Rule URL and paste the full URL.
   3. If you want Gremlin to evaluate a custom PromQL expression, select Enter a PromQL and enter the expression in the text box.
5. Click Test Health Check to verify connectivity.
6. Optionally, change the Polling Interval to change how frequently Gremlin polls Prometheus during testing.
7. Optionally, choose the category that best describes this test from the Category drop-down. This is used to provide recommended remediations if a test fails.
8. Click Create Health Check.