* initial prefer same data center https://github.com/seaweedfs/seaweedfs/issues/3404 * GetDataCenter * prefer same data center for ReplicationSource * GetDataCenterId * remove glog
How replication works ====== All metadata changes within current cluster would be notified to a message queue. If the meta data change is from other clusters, this metadata would change would not be notified to the message queue. So active<=>active replication is possible. All metadata changes would be published as metadata changes. So all mounts listening for metadata changes will get updated.