Thanks Ravi for the pointer. I will look into the pointed out source. Rahul
On Fri, May 17, 2013 at 11:44 PM, Ravi Prakash <[email protected]> wrote: > Hi, > > I couldn't find any code that would relay this failure to the NN. The > relevant code is in DFSOutputStream:DataStreamer:processDatanodeError() > > For trunk: > https://svn.apache.org/repos/asf/hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSOutputStream.java > For 0.20: > http://javasourcecode.org/html/open-source/hadoop/hadoop-0.20.203.0/org/apache/hadoop/hdfs/DFSClient.DFSOutputStream.java.html > > I believe the assumption here is that the NN should independently discover > the failed node. Also, some failures might not be worthy of being reported > because the DN is expected to recover from them. > > Ravi. > > > ------------------------------ > *From:* Rahul Bhattacharjee <[email protected]> > *To:* "[email protected]" <[email protected]> > *Sent:* Friday, May 17, 2013 12:10 PM > *Subject:* HDFS write failures! > > Hi, > > I was going through some documents about HDFS write pattern. It looks like > the write pipeline is closed when a error is encountered and the faulty > node is taken out of the pipeline and the write continues.Few other > intermediate steps are to move the un-acked packets from ack queue to the > data queue. > > My question is , is this faulty data node is reported to the NN and > whether NN would continue to use it as a valid DN while serving other write > requests in future or will it make it as faulty ? > > Thanks, > Rahul > > >
