Help 4 CDH

1. failed to start name node (hadoop)
   1. check the permission of command(s) which are used to perform name node related processes such as /bin/df
   2. modify permission(s) properly, if necessary
   3. delete the name node dir
   4. retry
   5. it is recommended to check and modify the permission of command(s) before installing HDFS, otherwise HDFS may not be installed correctly
2. line length exceeds max (flume)
   1. increase deserializer.maxlinelength
      1. agent01.sources.source01.deserializer.maxLineLength
3. the channel is full (flume)
   1. increase memory capacity
      1. agent01.channels.channel01.capacity
4. fail to extract date information by using specified date format (flume)
   1. check LANG configuration
      1. LANG="en_US.UTF-8"
5. failed parsing date from field (logstash)
   1. set locale to en

      1. date {
               locale => en
               match => [ "timestamp" , "dd/MMM/yyyy:HH:mm:ss Z" ]
         }

6. could not load ffi provider (logstash)
   1. configure to use another directory instead of /tmp or 
   2. mount -o remount,exec /tmp