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

				info.Disks = getOfflineDisks(client.host.String(), globalEndpoints)
			}
			replies[idx] = info
		}(client, i)
	}
	wg.Wait()

	// Add local to this server.
	replies = append(replies, objLayer.LocalStorageInfo(ctx, metrics))

	storageInfo.Backend = objLayer.BackendInfo()
	for _, sinfo := range replies {
		storageInfo.Disks = append(storageInfo.Disks, sinfo.Disks...)
	}

	if err := signRequestV4(req, cred.AccessKey, cred.SecretKey); err != nil {
		t.Fatalf("Unable to initialized new signed http request %s", err)
	}
	return req
}

// Tests is requested authenticated function, tests replies for s3 errors.
func TestIsReqAuthenticated(t *testing.T) {
	ctx, cancel := context.WithCancel(GlobalContext)
	defer cancel()

	objLayer, fsDir, err := prepareFS(ctx)
	if err != nil {
		t.Fatal(err)
	}

 *  Fix: Don't resolve DNS addresses when connecting through a SOCKS proxy.
 *  Fix: Drop the synthetic `OkHttp-Selected-Protocol` response header.
 *  Fix: Support 204 and 205 'No Content' replies in the logging interceptor.
 *  New: Add `Call.isExecuted()`.


## Version 2.6.0

_2015-11-22_

 *  **New Logging Interceptor.** The `logging-interceptor` subproject offers

	// Default deleteMarker to true if object is under versioning
	deleteMarker := opts.Versioned

	if opts.VersionID != "" {
		// case where replica version needs to be deleted on target cluster
		if versionFound && opts.DeleteMarkerReplicationStatus() == replication.Replica {
			markDelete = false
		}
		if opts.VersionPurgeStatus().Empty() && opts.DeleteMarkerReplicationStatus().Empty() {
			markDelete = false
		}

    # sessionToken: SESSION-TOKEN # Optional only available when rotating credentials are used

  # NOTE: All flags are optional
  # - filtering criteria only applies for all source objects match the criteria
  # - configurable notification endpoints
  # - configurable retries for the job (each retry skips successfully previously replaced objects)
  flags:
    filter:

    }

    /**
     * Gets the number of replicas for the queue index.
     *
     * @return the number of queue replicas
     */
    @Override
    public int getQueueReplicas() {
        return ComponentUtil.getFessConfig().getIndexDocumentCrawlerQueueNumberOfReplicasAsInteger();
    }

    /**
     * Gets the number of replicas for the data index.
     *
     * @return the number of data replicas

replication is configured, any incoming uploads and metadata changes to versions created on the target, will sync back to the source and be marked as `REPLICA` on the source. AWS, as well as MinIO do not by default sync metadata changes on a object version marked `REPLICA` back to source. This requires a setting in the replication configuration called [replica modification sync](https://aws.amazon.com/about-aws/whats-new/2020/12/amazon-s3-replication-adds-support-two-way-replication/).

For active-active...

# Automatic Site Replication

This feature allows multiple independent MinIO sites (or clusters) that are using the same external IDentity Provider (IDP) to be configured as replicas. In this situation the set of replica sites are referred to as peer sites or just sites. When site-replication is enabled on a set of sites, the following changes are replicated to all other sites:

- Creation and deletion of buckets and objects

        int result = BigIntegerMath.log2(x, mode);
        assertTrue(ZERO.setBit(result).compareTo(x) >= 0);
        assertTrue(result == 0 || ZERO.setBit(result - 1).compareTo(x) < 0);
      }
    }
  }

  // Relies on the correctness of isPowerOfTwo(BigInteger).
  public void testLog2Exact() {
    for (BigInteger x : POSITIVE_BIGINTEGER_CANDIDATES) {
      // We only expect an exception if x was not a power of 2.