Date: Tue, 21 Jul 2020 00:36:14 GMT
```

### Checking cluster health for maintenance

You may query the cluster probe endpoint to check if the node which received the request can be taken down for maintenance, if the server replies back '412 Precondition Failed' this means you will lose HA. '200 OK' means you are okay to proceed.

```
curl http://minio1:9001/minio/health/cluster?maintenance=true
HTTP/1.1 412 Precondition Failed
Accept-Ranges: bytes

	onlineDisks, metaArr = shuffleDisksAndPartsMetadataByIndex(onlineDisks, metaArr, fi)

	// For negative length read everything.
	if length < 0 {
		length = fi.Size - startOffset
	}

	// Reply back invalid range if the input offset and length fall out of range.
	if startOffset > fi.Size || startOffset+length > fi.Size {
		return InvalidRange{startOffset, length, fi.Size}
	}

	// Get start part index and offset.

                                </table>
                            </div>
                            <div class="card-footer">
                                <button type="submit" class="btn btn-default" name="list" value="back">
                                    <em class="fa fa-arrow-circle-left">
                                    <la:message key="labels.crud_button_back"/>
                                </button>

## Prerequisites

Install Dex by following [Dex Getting Started Guide](https://dexidp.io/docs/getting-started/)

### Start Dex

```

cygwin=false
darwin=false
mingw=false
case "$(uname)" in
CYGWIN*) cygwin=true ;;
MINGW*) mingw=true ;;
Darwin*)
  darwin=true
  # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
  # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
  if [ -z "$JAVA_HOME" ]; then
    if [ -x "/usr/libexec/java_home" ]; then
      JAVA_HOME="$(/usr/libexec/java_home)"

        item.id = 50L;
        assertEquals(50L, item.getId());

        // Second modification
        item.id = 100L;
        assertEquals(100L, item.getId());

        // Third modification back to 0
        item.id = 0L;
        assertEquals(0L, item.getId());
    }

    /**
     * Concrete implementation of DictionaryItem for testing purposes.

     * information that is available at the point the problem occurs and as such merely serves as best effort
     * to provide information to the user to track the problem back to its origin.
     *
     * @return The identifier of the model from which the problem originated or an empty string if unknown, never
     *         {@code null}.
     */
    @Nonnull
    String getModelId();

   *   <li>{@linkplain LoadingCache#refresh refreshing of entries}, including {@linkplain
   *       CacheBuilder#refreshAfterWrite automated refreshing}
   *   <li>{@linkplain LoadingCache#getAll bulk loading requests}, including {@linkplain
   *       CacheLoader#loadAll bulk loading implementations}
   * </ul>
   *
   * <p><b>Warning:</b> For any given key, every {@code loader} used with it should compute the same

            alternatingKeysAndValues[previousKeyIndex ^ 1] = value;
            continue entries;
          }
        }
        if (outI < i) { // if outI == i don't bother writing the values back where they came from
          alternatingKeysAndValues[outKeyIndex] = key;
          alternatingKeysAndValues[outKeyIndex ^ 1] = value;
        }
        outI++;
      }

    /**
     * Represents an API response for bulk operations, containing a list of processed items.
     */
    public static class ApiBulkResponse extends ApiResponse {
        /**
         * Constructs an empty ApiBulkResponse.
         */
        public ApiBulkResponse() {
            // NOP
        }

        /**
         * The list of items processed in the bulk operation.
         */