Hi, The function of yarn.nodemanager.aux-services is to run any custom Service [1] implementations from the user, in the YARN NodeManager's runtime. The "aux" stands for auxiliary.
One such example of where this comes useful is the ShuffleHandler [2] service, which helps MR do its shuffle work, without needing the NM itself to provide a shuffle service unnecessarily (in case MR is not required). Therefore, a ShuffleHandler is necessary to be configured if you need to run MR2 apps (jobs), but not otherwise. A clear difference, in case you're confused between MR2 and YARN, can be found at [3]. Do feel free to ask any further questions you have. [1] - http://svn.apache.org/viewvc/hadoop/common/branches/branch-2/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/service/Service.java?view=markup [2] - http://svn.apache.org/viewvc/hadoop/common/branches/branch-2/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-shuffle/src/main/java/org/apache/hadoop/mapred/ShuffleHandler.java?view=markup [3] - http://www.cloudera.com/blog/2012/10/mr2-and-yarn-briefly-explained/ On Mon, Jan 28, 2013 at 6:43 PM, YouPeng Yang <yypvsxf19870...@gmail.com> wrote: > Hi All > I am wondering what the yarn.nodemanager.aux-services stands for 。 > there even is not description about it in the yarn-default.xml。So i‘ve just > ignored it when i tried the example,as a result ,it failed。 > I have do some google，however，everyone just setup it in the > yarn-site.xml,but no one tells the description about it。 > please,helps will be appreciated . > > . > -- Harsh J
