diff --git a/hadoop/2.8.1/Dockerfile b/hadoop/2.8.1/Dockerfile
index 6af0869..1f9e88e 100644
--- a/hadoop/2.8.1/Dockerfile
+++ b/hadoop/2.8.1/Dockerfile
@@ -47,11 +47,9 @@ ADD yarn-site.xml $HADOOP_HOME/etc/hadoop/yarn-site.xml
 ADD slaves $HADOOP_HOME/etc/hadoop/slaves
 
 
-RUN sed -i "/^export JAVA_HOME=.*/c export JAVA_HOME=${JAVA_HOME}\nexport HADOOP_HOME=${HADOOP_HOME}\nexport HADOOP_PREFIX=${HADOOP_PREFIX}/" etc/hadoop/hadoop-env.sh
+RUN sed -i "s|export JAVA_HOME=.*|export JAVA_HOME=${JAVA_HOME}\nexport HADOOP_HOME=${HADOOP_HOME}\nexport HADOOP_PREFIX=${HADOOP_PREFIX}|g" $HADOOP_PREFIX/etc/hadoop/hadoop-env.sh
 
-RUN sed -i "/^export HADOOP_CONF_DIR=.*/c export HADOOP_CONF_DIR=$HADOOP_PREFIX/etc/hadoop/" $HADOOP_PREFIX/etc/hadoop/hadoop-env.sh
-
-RUN sed -i '/^export HADOOP_CONF_DIR/ s:.*:export HADOOP_CONF_DIR=$HADOOP_PREFIX/etc/hadoop/:' $HADOOP_PREFIX/etc/hadoop/hadoop-env.sh
+RUN sed -i "s|export HADOOP_CONF_DIR=.*|export HADOOP_CONF_DIR=${HADOOP_PREFIX}/etc/hadoop/" $HADOOP_PREFIX/etc/hadoop/hadoop-env.sh
 
 WORKDIR $HADOOP_HOME