Monitoring and Alerting using Prometheus
MinIO publishes cluster and node metrics using the Prometheus Data Model. The procedure on this page documents the following:
Configuring a Prometheus service to scrape and display metrics from a MinIO deployment
Configuring an Alert Rule on a MinIO Metric to trigger an AlertManager action
Prerequisites
This procedure requires the following:
An existing Prometheus deployment with backing Alert Manager
An existing MinIO deployment with network access to the Prometheus deployment
An
mc
installation on your local host configured to access the MinIO deployment
Configure Prometheus to Collect and Alert using MinIO Metrics
1) Generate the Scrape Configuration
Use the mc admin prometheus generate
command to generate the scrape configuration for use by Prometheus in making scraping requests:
mc admin prometheus generate ALIAS
Replace ALIAS
with the alias
of the MinIO deployment.
The command returns output similar to the following:
scrape_configs:
- job_name: minio-job
bearer_token: TOKEN
metrics_path: /minio/v2/metrics/cluster
scheme: https
static_configs:
- targets: [minio.example.net]
Set the
job_name
to a value associated to the MinIO deployment.Use a unique value to ensure isolation of the deployment metrics from any others collected by that Prometheus service.
MinIO deployments started with
MINIO_PROMETHEUS_AUTH_TYPE
set to"public"
can omit thebearer_token
field.Set the
scheme
to http for MinIO deployments not using TLS.Set the
targets
array with a hostname that resolves to the MinIO deployment.This can be any single node, or a load balancer/proxy which handles connections to the MinIO nodes.
For Prometheus deployments in the same cluster as the MinIO Tenant, you can specify the service DNS name for the
minio
service.For Prometheus deployments external to the cluster, you must specify an ingress or load balancer endpoint configured to route connections to and from the MinIO Tenant.
2) Restart Prometheus with the Updated Configuration
Append the scrape_configs
job generated in the previous step to the configuration file:
global:
scrape_interval: 15s
scrape_configs:
- job_name: minio-job
bearer_token: TOKEN
metrics_path: /minio/v2/metrics/cluster
scheme: https
static_configs:
- targets: [minio.example.net]
Start the Prometheus cluster using the configuration file:
prometheus --config.file=prometheus.yaml
3) Analyze Collected Metrics
Prometheus includes a expression browser. You can execute queries here to analyze the collected metrics.
The following query examples return metrics collected by Prometheus:
minio_cluster_disk_online_total{job="minio-job"}[5m]
minio_cluster_disk_offline_total{job="minio-job"}[5m]
minio_bucket_usage_object_total{job="minio-job"}[5m]
minio_cluster_capacity_usable_free_bytes{job="minio-job"}[5m]
See Available Metrics for a complete list of published metrics.
4) Configure an Alert Rule using MinIO Metrics
You must configure Alert Rules on the Prometheus deployment to trigger alerts based on collected MinIO metrics.
The following example alert rule files provide a baseline of alerts for a MinIO deployment. You can modify or otherwise use these examples as guidance in building your own alerts.
groups:
- name: minio-alerts
rules:
- alert: NodesOffline
expr: avg_over_time(minio_cluster_nodes_offline_total{job="minio-job"}[5m]) > 0
for: 10m
labels:
severity: warn
annotations:
summary: "Node down in MinIO deployment"
description: "Node(s) in cluster {{ $labels.instance }} offline for more than 5 minutes"
- alert: DisksOffline
expr: avg_over_time(minio_cluster_disk_offline_total{job="minio-job"}[5m]) > 0
for: 10m
labels:
severity: warn
annotations:
summary: "Disks down in MinIO deployment"
description: "Disks(s) in cluster {{ $labels.instance }} offline for more than 5 minutes"
Specify the path to the alert file to the Prometheus configuration as part of the rule_files
key:
global:
scrape_interval: 5s
rule_files:
- minio-alerting.yml
Once triggered, Prometheus sends the alert to the configured AlertManager service.
5) (Optional) Configure MinIO Console to Query Prometheus
The Console also supports displaying time-series and historical data by querying a Prometheus service configured to scrape data from the MinIO deployment.

To enable historical data visualization in MinIO Console, set the following environment variables on each node in the MinIO deployment:
Set
MINIO_PROMETHEUS_URL
to the URL of the Prometheus serviceSet
MINIO_PROMETHEUS_JOB_ID
to the unique job ID assigned to the collected metrics
Restart the MinIO deployment and visit the Monitoring pane to see the historical data views.