when loading a huge file into hadoop cluster , what happends if the client failed while transfering data to datanodes? -

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for example,the file 1280mb , hdfs block 128mb，what happends when the
client transfered 3 blocks , failed? namenode obtain file of 3 blocks or delete 3 blocks ？

no not delete 3 blocks. here how works, assume block 4 in next of queue maintained fsdataouputstream. after writes x bytes due network issue datanode fails, pipeline first closed , data written deleted, new datanode given new identity , added queue , same communicated name node update metadata information block 4 , data written newly identified datanode starting 1st byte of block. anatomy of file write in definitive guide in better understanding on how done.


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