MR Client's ShuffleHandler uses it by default. Tweakable via mapreduce.shuffle.port in mapred-site.xml.
While you are at it, would you also like to offer a quick patch on https://issues.apache.org/jira/browse/MAPREDUCE-3493 to document this in mapred-default.xml file? 2012/4/4 Radim Kolar <h...@filez.com>: > Which application/service runs on port 8080 in YARN by default? I need to > change port. There have been recent default port changes since the first 0.23-based release, for better 'series' among the new services. Read about those at https://issues.apache.org/jira/browse/MAPREDUCE-3920 (Just FYI). These changes will be in 2.0.0. -- Harsh J
