Similar to this previously posted problem, I am unable to start my ResourceManager.  This started after I upgraded my box (Ubuntu 12.04 to 14.04), which most likely also upgrade CDH to 5.5.2.   Error: 2016-02-18 16:40:25,196 FATAL org.apache.hadoop.yarn.server.resourcemanager.ResourceManager: Error starting ResourceManager org.apache.hadoop.yarn.webapp.WebAppException: Error starting http server at org.apache.hadoop.yarn.webapp.WebApps$Builder.start(WebApps.java:278) at org.apache.hadoop.yarn.server.resourcemanager.ResourceManager.startWepApp(ResourceManager.java:985) at org.apache.hadoop.yarn.server.resourcemanager.ResourceManager.serviceStart(ResourceManager.java:1085) at org.apache.hadoop.service.AbstractService.start(AbstractService.java:193) at org.apache.hadoop.yarn.server.resourcemanager.ResourceManager.main(ResourceManager.java:1217) Caused by: java.io.IOException: Problem in starting http server. Server handlers failed at org.apache.hadoop.http.HttpServer2.start(HttpServer2.java:900) at org.apache.hadoop.yarn.webapp.WebApps$Builder.start(WebApps.java:273) ... 4 more   As suggested in the above post, I tried enabling debugging (added "log4j.logger.org.apache.hadoop.yarn.server.resourcemanager=DEBUG,console" to /etc/hadoop/conf/log4j.properties), but I still don't see any reasons this is failing.   Here's my /var/log/hadoop-yarn/yarn-yarn-resourcemanager-elgordo.log file: http://pastebin.com/VPk96KAg   Here's my /var/log/hadoop-yarn/yarn-yarn-resourcemanager-elgordo.out file: http://pastebin.com/2penUUQS   There's a Hadoop JIRA bug fixed in Hadoop 2.7 that sounds like the fix I need (https://issues.apache.org/jira/browse/HADOOP-11754); but I don't see why this is failing for me, but not for everyone else.  Is there a configuration change that I can make to avoid this particular Hadoop bug?     There's an option Cloudera JIRA issue that looks similar: https://issues.cloudera.org/browse/DISTRO-754 (no replies on it though). ... View more