Metrics and Alerts
MinIO publishes cluster and node metrics using the Prometheus Data Model. You can use any scraping tool to pull metrics data from MinIO for further analysis and alerting.
MinIO provides a scraping endpoint for cluster-level metrics:
http://minio.example.net:9000/minio/v2/metrics/cluster
Replace http://minio.example.net
with the hostname of any node in the MinIO deployment.
For deployments with a load balancer managing connections between MinIO nodes, specify the address of the load balancer.
MinIO by default requires authentication for scraping the metrics endpoints.
Use the mc admin prometheus generate
command to generate the necessary bearer tokens.
You can alternatively disable metrics endpoint authentication by setting MINIO_PROMETHEUS_AUTH_TYPE
to public
.
MinIO Console Metrics Dashboard
The MinIO Console provides a point-in-time metrics dashboard by default:

The Console also supports displaying time-series and historical data by querying a Prometheus service configured to scrape data from the MinIO deployment. Specifically, the MinIO Console uses Prometheus query API to retrieve stored metrics data and display the following visualizations:
Usage - provides historical and on-demand visualization of overall usage and status
Traffic - provides historical and on-demand visualization of network traffic
Resources - provides historical and on-demand visualization of resources (compute and storage)
Info - provides point-in-time status of the 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
MinIO also publishes a Grafana Dashboard for visualizing collected metrics. For more complete documentation on configuring a Prometheus-compatible data source for Grafana, see Grafana Support for Prometheus.
Available Metrics
MinIO publishes the following metrics, where each metric includes a label for the MinIO server which generated that metric.
Object and Bucket Metrics
- minio_bucket_objects_size_distribution
Distribution of object sizes in a given bucket. You can identify the bucket using the
{ bucket="STRING" }
label.
- minio_bucket_objects_version_distribution
Distribution of number of versions per object in a given bucket. You can identify the bucket using the
{ bucket="STRING" }
label.
- minio_bucket_usage_object_total
Total number of objects in a given bucket. You can identify the bucket using the
{ bucket="STRING" }
label.
- minio_bucket_usage_total_bytes
Total bucket size in bytes in a given bucket. You can identify the bucket using the
{ bucket="STRING" }
label.
Replication Metrics
These metrics are only populated for MinIO clusters with Server-Side Bucket Replication enabled.
- minio_bucket_replication_failed_bytes
Total number of bytes that failed at least once to replicate for a given bucket. You can identify the bucket using the
{ bucket="STRING" }
label
- minio_bucket_replication_pending_bytes
Total number of bytes pending to replicate for a given bucket. You can identify the bucket using the
{ bucket="STRING" }
label
- minio_bucket_replication_received_bytes
Total number of bytes replicated to this bucket from another source bucket. You can identify the bucket using the
{ bucket="STRING" }
label.
- minio_bucket_replication_sent_bytes
Total number of bytes replicated to the target bucket. You can identify the bucket using the
{ bucket="STRING" }
label.
Capacity Metrics
- minio_node_disk_free_bytes
Total storage available on a specific drive for a node in the MinIO deployment. You can identify the drive and node using the
{ disk="/path/to/disk",server="STRING"}
labels respectively.
Lifecycle Management Metrics
- minio_cluster_ilm_transitioned_bytes
Total number of bytes transitioned using tiering/transition lifecycle management rules
- minio_cluster_ilm_transitioned_objects
Total number of objects transitioned using tiering/transition lifecycle management rules
- minio_cluster_ilm_transitioned_versions
Total number of non-current object versions transitioned using tiering/transition lifecycle management rules
- minio_node_ilm_transition_pending_tasks
Total number of pending object transition tasks
- minio_node_ilm_expiry_pending_tasks
Total number of pending object expiration tasks
- minio_node_ilm_expiry_active_tasks
Total number of active object expiration tasks
Node and Drive Health Metrics
- minio_heal_time_last_activity_nano_seconds
Time elapsed (in nano seconds) since last self healing activity. This is set to -1 until initial self heal
- minio_node_storage_class_standard_parity
The configured value of
MINIO_STORAGE_CLASS_STANDARD
.Use this to alert for changes to the Standard erasure parity.
- minio_node_storage_class_rrs_parity
The configured value of
MINIO_STORAGE_CLASS_RRS
.Use this to alert for changes to the Reduced erasure parity.
Notification Queue Metrics
- minio_audit_failed_messages
Total number of audit messages which failed to send since last server start.
Scanner Metrics
S3 Metrics
- minio_bucket_traffic_sent_bytes
Total number of bytes of S3 traffic sent per bucket. You can identify the bucket using the
{ bucket="STRING" }
label.
- minio_bucket_traffic_received_bytes
Total number of bytes of S3 traffic received per bucket. You can identify the bucket using the
{ bucket="STRING" }
label.
- minio_s3_requests_canceled_total
Total number S3 requests that were canceled from the client while processing.
IAM Metrics
IAM Plugin Metrics
Note
The metrics in this section require that you have configured the MinIO External Identity Management Plugin.
- minio_node_iam_plugin_authn_service_last_succ_seconds
Time (in seconds) since last successful request to the external IDP service.
- minio_node_iam_plugin_authn_service_last_fail_seconds
Time (in seconds) since last failed request to the external IDP service.
- minio_node_iam_plugin_authn_service_total_requests_minute
Total requests count to the external IDP service in the last full minute.
- minio_node_iam_plugin_authn_service_failed_requests_minute
Count of the failed requests to the external IDP service in the last full minute.
Internal Metrics
- minio_inter_node_traffic_dial_errors
Total number of internode TCP dial timeouts and errors.
New in version MinIO: RELEASE.2023-04-28T18-11-17Z
This metric is available on the MinIO Dashboard if Prometheus and Grafana are enabled.
- minio_node_file_descriptor_limit_total
Limit on total number of open file descriptors for the MinIO Server process.
- minio_node_file_descriptor_open_total
Total number of open file descriptors by the MinIO Server process.
- minio_node_io_rchar_bytes
Total bytes read by the process from the underlying storage system including cache,
/proc/[pid]/io rchar
- minio_node_io_read_bytes
Total bytes read by the process from the underlying storage system,
/proc/[pid]/io read_bytes
Key Management System (KMS) Metrics
- minio_cluster_kms_request_error
Number of KMS requests that failed due to some error. (HTTP 4xx status code).