# How to monitor MinIO server with Prometheus [](https://slack.min.io)
[Prometheus](https://prometheus.io) is a cloud-native monitoring platform, built originally at SoundCloud. Prometheus offers a multi-dimensional data model with time series data identified by metric name and key/value pairs. The data collection happens via a pull model over HTTP/HTTPS. Targets to pull data from are discovered via service discovery or static configuration.
MinIO exports Prometheus compatible data by default as an authorized endpoint at `/minio/prometheus/metrics`. Users looking to monitor their MinIO instances can point Prometheus configuration to scrape data from this endpoint.
This document explains how to setup Prometheus and configure it to scrape data from MinIO servers.
- [3.2 Public Prometheus config](#32-public-prometheus-config)
- [4. Update `scrape_configs` section in prometheus.yml](#4-update-scrapeconfigs-section-in-prometheusyml)
- [5. Start Prometheus](#5-start-prometheus)
- [List of metrics exposed by MinIO](#list-of-metrics-exposed-by-minio)
## Prerequisites
To get started with MinIO, refer [MinIO QuickStart Document](https://docs.min.io/docs/minio-quickstart-guide). Follow below steps to get started with MinIO monitoring using Prometheus.
### 1. Download Prometheus
[Download the latest release](https://prometheus.io/download) of Prometheus for your platform, then extract it
```sh
tar xvfz prometheus-*.tar.gz
cd prometheus-*
```
Prometheus server is a single binary called `prometheus` (or `prometheus.exe` on Microsoft Windows). Run the binary and pass `--help` flag to see available options
```sh
./prometheus --help
usage: prometheus [<flags>]
The Prometheus monitoring server
. . .
```
Refer [Prometheus documentation](https://prometheus.io/docs/introduction/first_steps/) for more details.
### 2. Configure authentication type for Prometheus metrics
MinIO supports two authentication modes for Prometheus either `jwt` or `public`, by default MinIO runs in `jwt` mode. To allow public access without authentication for prometheus metrics set environment as follows.
```
export MINIO_PROMETHEUS_AUTH_TYPE="public"
minio server ~/test
```
### 3. Configuring Prometheus
#### 3.1 Authenticated Prometheus config
> If MinIO is configured to expose metrics without authentication, you don't need to use `mc` to generate prometheus config. You can skip reading further and move to 3.2 section.
The Prometheus endpoint in MinIO requires authentication by default. Prometheus supports a bearer token approach to authenticate prometheus scrape requests, override the default Prometheus config with the one generated using mc. To generate a Prometheus config for an alias, use [mc](https://docs.min.io/docs/minio-client-quickstart-guide) as follows `mc admin prometheus generate <alias>`.
The command will generate the `scrape_configs` section of the prometheus.yml as follows:
```yaml
scrape_configs:
- job_name: minio-job
bearer_token: <secret>
metrics_path: /minio/prometheus/metrics
scheme: http
static_configs:
- targets: ['localhost:9000']
```
#### 3.2 Public Prometheus config
If Prometheus endpoint authentication type is set to `public`. Following prometheus config is sufficient to start scraping metrics data from MinIO.
```yaml
scrape_configs:
- job_name: minio-job
metrics_path: /minio/prometheus/metrics
scheme: http
static_configs:
- targets: ['localhost:9000']
```
### 4. Update `scrape_configs` section in prometheus.yml
To authorize every scrape request, copy and paste the generated `scrape_configs` section in the prometheus.yml and restart the Prometheus service.
### 5. Start Prometheus
Start (or) Restart Prometheus service by running
```sh
./prometheus --config.file=prometheus.yml
```
Here `prometheus.yml` is the name of configuration file. You can now see MinIO metrics in Prometheus dashboard. By default Prometheus dashboard is accessible at `http://localhost:9090`.
## List of metrics exposed by MinIO
MinIO server exposes the following metrics on `/minio/prometheus/metrics` endpoint. All of these can be accessed via Prometheus dashboard. The full list of exposed metrics along with their definition is available in the demo server at https://play.min.io:9000/minio/prometheus/metrics
All metrics are labeled by `bucket`, each metric is displayed per bucket. `buckets_objects_histogram` is additionally labeled by `object_size` string which is represented by any of the following values
`<gateway_type>` changes based on the gateway in use can be 's3', 'gcs' or 'azure'. Other metrics are labeled with `method` that identifies HTTP GET, HEAD, PUT and POST requests to the backend.
MinIO exposes self-healing related metrics for erasure-code deployments _only_. These metrics are _not_ available on Gateway or Single Node, Single Drive deployments. Note that these metrics will be exposed _only_ when there is a relevant event happening on MinIO server.
| `self_heal_time_since_last_activity` | Time elapsed since last self-healing related activity |
| `self_heal_objects_scanned` | Number of objects scanned by self-healing thread in its current run. This will reset when a fresh self-healing run starts. This is labeled with the object type scanned |
| `self_heal_objects_healed` | Number of objects healing by self-healing thread in its current run. This will reset when a fresh self-healing run starts. This is labeled with the object type scanned |
| `self_heal_objects_heal_failed` | Number of objects for which self-healing failed in its current run. This will reset when a fresh self-healing run starts. This is labeled with disk status and its endpoint |
