Another question: is there some kind of documentation (other than the code) that specifies the kind of serialization algorithm Writables use? I think I may have to port the concept over to another language.
Thanks, Dhaivat On Sun, Mar 23, 2014 at 9:11 AM, Dhaivat Pandya <dhaivatpan...@gmail.com>wrote: > Thank you very much, Andrew. > > > On Sat, Mar 22, 2014 at 7:02 PM, Andrew Wang <andrew.w...@cloudera.com>wrote: > >> 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 >> > >> > >
