Hadoop hdfs tips and tricks
Active namenode in a cluster
# lookup active nn nn_list=`hdfs getconf -namenodes` echo Namenodes found: $nn_list active_node=‘’ #for nn in $( hdfs getconf -namenodes ); do for nn in $nn_list ; do echo Checking nn for active: $nn if hadoop fs -test -e hdfs://$nn/ ; then echo Found active nn active_node=$nn break fi done echo active nn is $active_node