_ = x[storageMetricVerifyFile-16]
	_ = x[storageMetricWriteAll-17]
	_ = x[storageMetricDeleteVersion-18]
	_ = x[storageMetricWriteMetadata-19]
	_ = x[storageMetricUpdateMetadata-20]
	_ = x[storageMetricReadVersion-21]
	_ = x[storageMetricReadXL-22]
	_ = x[storageMetricReadAll-23]
	_ = x[storageMetricStatInfoFile-24]
	_ = x[storageMetricReadMultiple-25]
	_ = x[storageMetricDeleteAbandonedParts-26]
	_ = x[storageMetricDiskInfo-27]

	_ = x[HandlerUpdateMetadata-15]
	_ = x[HandlerWriteMetadata-16]
	_ = x[HandlerCheckParts-17]
	_ = x[HandlerRenameData-18]
	_ = x[HandlerRenameFile-19]
	_ = x[HandlerReadAll-20]
	_ = x[HandlerServerVerify-21]
	_ = x[HandlerTrace-22]
	_ = x[HandlerListen-23]
	_ = x[HandlerDeleteBucketMetadata-24]
	_ = x[HandlerLoadBucketMetadata-25]
	_ = x[HandlerReloadSiteReplicationConfig-26]
	_ = x[HandlerReloadPoolMeta-27]

Accept-Ranges: bytes
Content-Length: 0
Server: MinIO
Vary: Origin
X-Amz-Bucket-Region: us-east-1
X-Minio-Write-Quorum: 3
X-Amz-Request-Id: 16239D6AB80EBECF
X-Xss-Protection: 1; mode=block
Date: Tue, 21 Jul 2020 00:36:14 GMT
```

### Cluster-readable probe

The reply is '200 OK' if cluster has read quorum if not it returns '503 Service Unavailable'.

```
curl http://minio1:9001/minio/health/cluster/read

		expectedErr    error
	}{
		{
			// valid: represents a restored object, 'pending' expiry.
			restoreHdr: `ongoing-request="false", expiry-date="Fri, 21 Dec 2012 00:00:00 GMT"`,
			expectedStatus: restoreObjStatus{
				ongoing: false,
				expiry:  time.Date(2012, 12, 21, 0, 0, 0, 0, time.UTC),
			},
			expectedErr: nil,
		},
		{
			// valid: represents an ongoing restore object request.

	_ = x[scannerMetricLastRealtime-16]
	_ = x[scannerMetricScanFolder-17]
	_ = x[scannerMetricScanCycle-18]
	_ = x[scannerMetricScanBucketDrive-19]
	_ = x[scannerMetricCompactFolder-20]
	_ = x[scannerMetricLast-21]
}