I am getting this error on startup of Hadoop on OSX 10.7:
Unable to load realm info from SCDynamicStore
put: org.apache.hadoop.hdfs.server.namenode.SafeModeException: Cannot create directory /user/travis/input/conf. Name node is in safe mode.
It doesn’t appear to be causing any issues with the functionality of Hadoop.
Matthew Buckett’s suggestion in HADOOP-7489 worked for me. Add the following to your hadoop-env.sh file:
export HADOOP_OPTS="-Djava.security.krb5.realm=OX.AC.UK -Djava.security.krb5.kdc=kdc0.ox.ac.uk:kdc1.ox.ac.uk"