drives.  Therefore, the number of drives you present must be a multiple of one of these numbers.  Each object is written to a single erasure-coding set.

Minio uses the largest possible EC set size which divides into the number of drives given. For example, *18 drives* are configured as *2 sets of 9 drives*, and *24 drives* are configured as *2 sets of 12 drives*.  This is true for scenarios when running MinIO as a standalone erasure coded deployment. In [distributed setup however node (affinity)...

| `minio_system_drive_used_inodes`               | Total used inodes on a drive. <br><br>Type: gauge                                       | `drive`, `set_index`, `drive_index`, `pool_index`, `server`        |

          "legendFormat": "Free [{{drive}}]",
          "refId": "C"
        }
      ],
      "title": "Drive Usage",
      "type": "timeseries"
    },
    {
      "datasource": {
        "type": "prometheus",
        "uid": "${DS_PROMETHEUS}"
      },
      "description": "",
      "fieldConfig": {
        "defaults": {
          "color": {
            "mode": "palette-classic"
          },

| `minio_node_drive_total_inodes`      | Total inodes on a drive.                                 |
| `minio_node_drive_used_inodes`       | Total inodes used on a drive.                            |
| `minio_node_drive_reads_per_sec`     | Reads per second on a drive.                             |
| `minio_node_drive_reads_kb_per_sec`  | Kilobytes read per second on a drive.                    |

two parity drives, 100 MiB file takes only approximately 114 MiB.

Below is a list of data/parity drives and corresponding _approximate_ storage space usage on a 16 drive MinIO deployment. The field _storage
usage ratio_ is simply the drive space used by the file after erasure-encoding, divided by actual file size.

| Total Drives (N) | Data Drives (D) | Parity Drives (P) | Storage Usage Ratio |

				if deploymentID != "" {
					newFormat.ID = deploymentID
				}
				drive := pool.Endpoints[i*setDriveCount+j]
				fmtBytes, err := json.Marshal(newFormat)
				if err != nil {
					//nolint:gocritic
					log.Fatalf("failed to marshal format.json for %s: %v", drive.String(), err)
				}
				fmtJSON := filepath.Join(drive.Host, drive.Path, minioMetaBucket, "format.json")
				embedFileInZip(fmtZipW, fmtJSON, fmtBytes, 0o600)

- **MinIO creates erasure-coding sets of _2_ to _16_ drives per set.  The number of drives you provide in total must be a multiple of one of those numbers.**
- **MinIO chooses the largest EC set size which divides into the total number of drives or total number of nodes given - making sure to keep the uniform distribution i.e each node participates equal number of drives per set**.

			return fmt.Errorf("%s drive is already being used in another erasure deployment. (Number of drives specified: %d but the number of drives found in the %s drive's format.json: %d)",
				disks[i], len(formats), humanize.Ordinal(i+1), len(formatErasure.Erasure.Sets)*len(formatErasure.Erasure.Sets[0]))
		}
		if len(formatErasure.Erasure.Sets[0]) != setDriveCount {

To host multiple tenants on a single machine, run one MinIO Server per tenant with a dedicated HTTPS port, configuration, and data directory.

### 1.1 Host Multiple Tenants on a Single Drive

Use the following commands to host 3 tenants on a single drive:

```sh
minio server --address :9001 /data/tenant1
minio server --address :9002 /data/tenant2
minio server --address :9003 /data/tenant3
```

		errs, fi, false, bucket, object, madmin.HealDeepScan)

	for diskIndex, disk := range erasureDisks {
		if diskIndex == 0 && disk != nil {
			t.Errorf("Drive not filtered as expected, drive: %d", diskIndex)
		}
		if diskIndex != 0 && disk == nil {
			t.Errorf("Drive erroneously filtered, driveIndex: %d", diskIndex)
		}
	}
	partsMetadata[0] = partsMetadataBackup // Revert before going to the next test