Hadoop on OSX "Unable to load realm info from SCDynamicStore"

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.

Solution 1:

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"

Solution 2:

As an update to this (and to address David Williams' point about Java 1.7), I experienced that only setting the .realm and .kdc properties was insufficient to stop the offending message.

However, by examining the source file that is omitting the message I was able to determine that setting the .krb5.conf property to /dev/null was enough to suppress the message. Obviously if you actually have a krb5 configuration, better to specify the actual path to it.

In total, my hadoop-env.sh snippet is as follows:

HADOOP_OPTS="${HADOOP_OPTS} -Djava.security.krb5.realm= -Djava.security.krb5.kdc="
HADOOP_OPTS="${HADOOP_OPTS} -Djava.security.krb5.conf=/dev/null"