Whenever a hadoop job hangs right after spitting out the following
11/04/08 13:52:59 INFO security.Groups: Group mapping impl=org.apache.hadoop.security.ShellBasedUnixGroupsMapping; cacheTimeout=300000
After 6 hours of diagnoses, I realized there are two possible problems
1) namenode needs formatting. You do this by going to your hadoop-hadoop/ directory and deleting everything in there and running
bin/hdfs namenode format
2) examine the logs and look for exceptions in the datnode, tasktracker
No comments:
Post a Comment