// Object for test case 6 - RRS StorageClass defined as Parity 2, MetaData in PutObject requesting Standard Storage Class
	object6 := "object6"
	metadata6 := make(map[string]string)
	metadata6["x-amz-storage-class"] = storageclass.STANDARD
	globalStorageClass.Update(storageclass.Config{
		Standard: storageclass.StorageClass{
			Parity: 4,
		},
		RRS: storageclass.StorageClass{
			Parity: 2,
		},
	})

				mapped = make([]byte, size)
				filled = make([]byte, size)
			}
			data = ei.V2Obj.EcM
			parity = ei.V2Obj.EcN
			if shards == 0 {
				shards = data + parity
			}
			idx = ei.V2Obj.EcIndex - 1
			fmt.Println("Read shard", ei.V2Obj.EcIndex, "Data shards", data, "Parity", parity, fmt.Sprintf("(%s)", file))
			if ei.V2Obj.Size != size {
				return fmt.Errorf("size mismatch. Meta size: %d", ei.V2Obj.Size)

```

Example:

```sh
export MINIO_SITE_REGION="us-west-0"
export MINIO_SITE_NAME="sfo-rack-1"
minio server /data
```

### Storage Class

		if m.IsValid() {
			tags["size"] = m.Size
			tags["mtime"] = m.ModTime.Format(http.TimeFormat)
			tags["data"] = m.Erasure.DataBlocks
			tags["parity"] = m.Erasure.ParityBlocks
		} else {
			tags["invalid-meta"] = true
			tags["data"] = er.setDriveCount - er.defaultParityCount
			tags["parity"] = er.defaultParityCount
		}

		// count the number of offline disks
		offline := 0

		// If storage class is not set during startup, default values are used
		// -- Default for Reduced Redundancy Storage class is, parity = 2
		// -- Default for Standard Storage class is, parity = 2 - disks 4, 5
		// -- Default for Standard Storage class is, parity = 3 - disks 6, 7
		// -- Default for Standard Storage class is, parity = 4 - disks 8 to 16
		if commonParityDrives == 0 {
			commonParityDrives, err = ecDrivesNoConfig(ep.DrivesPerSet)

f85-8dbc-131ff6028438","7c7dcc16-6c0d-4513-93c7-2ca3d2ca348a","dd9393ca-9dc4-40b2-a7e9-455522822d90","7c61eb5a-cbaa-4d45-b714-cf5b4cc82ef5","954b6edf-3e12-4f4b-8c4c-2b3014cbdfdb","0f37d8dc-aaa3-4113-89b0-0a2f4af8362c"]],"distributionAlgo":"SIPMOD+PARITY"}} multisitea/data/disterasure/xl3/.minio.sys/tmp/db01c92f-8f6d-438b-9f66-b105934f7c72 multisitea/data/disterasure/xl3/.minio.sys/tmp/.trash/.writable-check-635c94a5-cd73-4863-8db3-e84ca708dfc1.tmp multisitea/data/disterasure/xl3/.minio.sys/tmp/....

		Subsystem: storageClassSubsystem,
		Name:      "standard_parity",
		Help:      "standard storage class parity",
		Type:      gaugeMetric,
	}
}

func getNodeRRSParityMD() MetricDescription {
	return MetricDescription{
		Namespace: nodeMetricNamespace,
		Subsystem: storageClassSubsystem,
		Name:      "rrs_parity",
		Help:      "reduced redundancy storage class parity",
		Type:      gaugeMetric,
	}
}

### Allowed values for STANDARD storage class

`STANDARD` storage class implies more parity than `REDUCED_REDUNDANCY` class. So, `STANDARD` parity drives should be

- Greater than or equal to 2, if `REDUCED_REDUNDANCY` parity is not set.
- Greater than `REDUCED_REDUNDANCY` parity, if it is set.

Parity blocks can not be higher than data blocks, so `STANDARD` storage class parity can not be higher than N/2. (N being total number of drives)

reconstruct missing or corrupted data. MinIO uses Reed-Solomon code to shard objects into variable data and parity blocks. For example, in a 12 drive setup, an object can be sharded to a variable number of data and parity blocks across all the drives - ranging from six data and six parity blocks to ten data and two parity blocks.

By default, MinIO shards the objects across N/2 data and N/2 parity drives. Though, you can use [storage classes](https://github.com/minio/minio/tree/master/docs/erasure/storage-class)...

		t.Fatalf("Unable to format drives for erasure, %s", err)
	}

	ep := PoolEndpoints{Endpoints: endpoints}

	parity, err := ecDrivesNoConfig(16)
	if err != nil {
		t.Fatalf("Unexpected error during EC drive config: %v", err)
	}
	if _, err := newErasureSets(ctx, ep, storageDisks, format, parity, 0); err != nil {
		t.Fatalf("Unable to initialize erasure")
	}
}