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Szuyi commented on HADOOP-692: ------------------------------ I have a questions: Setting cluster topology map has to match physical network topology,dosen't it? I want to build the four level of physical network topology(/CoreDC/DC/rack/host)or more level. Does Rack aware has support ? > Rack-aware Replica Placement > ---------------------------- > > Key: HADOOP-692 > URL: https://issues.apache.org/jira/browse/HADOOP-692 > Project: Hadoop Common > Issue Type: Improvement > Affects Versions: 0.10.1 > Reporter: Hairong Kuang > Assignee: Hairong Kuang > Fix For: 0.11.0 > > Attachments: Rack_aware_HDFS_proposal.pdf, rack.patch > > > This issue assumes that HDFS runs on a cluster of computers that spread > across many racks. Communication between two nodes on different racks needs > to go through switches. Bandwidth in/out of a rack may be less than the total > bandwidth of machines in the rack. The purpose of rack-aware replica > placement is to improve data reliability, availability, and network bandwidth > utilization. The basic idea is that each data node determines to which rack > it belongs at the startup time and notifies the name node of the rack id upon > registration. The name node maintains a rackid-to-datanode map and tries to > place replicas across racks. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira