This page is intended as a summary of MinIO Erasure Coding. For a more complete explanation, see <https://min.io/docs/minio/linux/operations/concepts/erasure-coding.html>.

## Overview

MinIO supports two storage classes, Reduced Redundancy class and Standard class. These classes can be defined using environment variables
set before starting MinIO server. After the data and parity drives for each storage class are defined using environment variables,

package cmd

import "context"

const (
	configRRSParity      = "rrs_parity"
	configStandardParity = "standard_parity"
)

var (
	configRRSParityMD = NewGaugeMD(configRRSParity,
		"Reduced redundancy storage class parity")
	configStandardParityMD = NewGaugeMD(configStandardParity,
		"Standard storage class parity")
)

// loadClusterConfigMetrics - `MetricsLoaderFn` for cluster config

			Optional:    true,
			Type:        "string",
		},
		config.HelpKV{
			Key:         ClassRRS,
			Description: `set the parity count for reduced redundancy storage class` + defaultHelpPostfix(ClassRRS),
			Optional:    true,
			Type:        "string",
		},
		config.HelpKV{
			Key:         Optimize,

MINIO_STORAGE_CLASS_RRS: Format "EC:<Default_Parity_Reduced_Redundancy_Class>" (e.g. "EC:3"). This sets the number of parity drives for MinIO server in Reduced Redundancy mode. Objects are stored in Reduced Redundancy mode, if Put request specifies RRS storage class
Refer to the link https://github.com/minio/minio/tree/master/docs/erasure/storage-class for more information`,
	)

MinIO protects data against hardware failures and silent data corruption using erasure code and checksums. With the highest level of redundancy, you may lose up to half (N/2) of the total drives and still be able to recover the data.

## What is Erasure Code?

 * **Be respectful**: We expect people to work together to resolve conflict, assume good intentions,
   and act with empathy. Do not turn disagreements into personal attacks.

 * **Be collaborative**: Collaboration reduces redundancy and improves the quality of our work. We
   strive for transparency within our open source community, and we work closely with upstream
   developers and others in the free software community to coordinate our efforts.

```

Distributed erasure coded configuration with 2 sets, 16 drives per set across hosts.

```
minio server http://host{1...32}/disk1
```

Distributed erasure coded configuration with rack level redundancy 32 sets in total, 16 drives per set.

```
minio server http://rack{1...4}-host{1...8}.example.net/export{1...16}

> **NOTE:** **Each pool you add must have the same erasure coding parity configuration as the original pool, so the same data redundancy SLA is maintained.**

## 3. Test your setup

To test this setup, access the MinIO server via browser or [`mc`](https://min.io/docs/minio/linux/reference/minio-mc.html#quickstart).

## Explore Further

        }
    }

    private Collection<WeakMojoExecutionListener> getProvidedListeners() {
        // the same instance can be provided multiple times under different Key's
        // deduplicate instances to avoid redundant beforeXXX/afterXXX callbacks
        IdentityHashMap<WeakMojoExecutionListener, Object> listeners = new IdentityHashMap<>();
        for (Object provided : getScopeState().provided()) {

## List of Amazon S3 API's not supported on MinIO

We found the following APIs to be redundant or less useful outside of AWS S3. If you have a different view on any of the APIs we missed, please consider opening a [GitHub issue](https://github.com/minio/minio/issues) with relevant details on why MinIO must implement them.