Hi Dhaivat, Take a look at DatanodeRegistration and it's parent class DatanodeID. DR is a Writable, meaning it's a custom serialization format. Hadoop 2 uses protobuf for the RPC serialization rather than writables (with the exception of DN data transfer).
https://github.com/apache/hadoop-common/blob/branch-1.2/src/hdfs/org/apache/hadoop/hdfs/server/protocol/DatanodeRegistration.java https://github.com/apache/hadoop-common/blob/branch-1.2/src/hdfs/org/apache/hadoop/hdfs/protocol/DatanodeID.java Best, Andrew On Sat, Mar 22, 2014 at 1:16 PM, Dhaivat Pandya <dhaivatpan...@gmail.com>wrote: > Hi everyone, > > I'm currently working on an application that requires some important > details about the DataNode registration (w/ NameNode) procedure. > > Specifically, I have understood (after Wireshark-ing and looking through > the Hadoop code) that the DataNode is registered with the NameNode using a > single packet which tells the NameNode where the DataNode is "located" > (i.e. host and port). > > However, in this packet, I'm not clear as to what scheme is used to > serialize the DataNode information. I am running Hadoop 1.2.1. Any > information will be appreciated. > > Thank you, > > Dhaivat Pandya >
