我的配置是

hduser@worker1:/usr/local/hadoop/conf$ jps
The program 'jps' can be found in the following packages:
 * openjdk-6-jdk
 * openjdk-7-jdk
Ask your administrator to install one of them

我虽然安装了Java

hduser@worker1:/usr/local/hadoop/conf$ java -version
java version "1.6.0_23"
OpenJDK Runtime Environment (IcedTea6 1.11pre) (6b23~pre10-0ubuntu5)
OpenJDK 64-Bit Server VM (build 20.0-b11, mixed mode)

hduser@worker1:/usr/local/hadoop/conf$ echo $JAVA_HOME 
/usr/lib/jvm/java-1.6.0-openjdk

并在 conf/hadoop-env.sh

hduser@worker1:/usr/local/hadoop/conf$ cat hadoop-env.sh | grep JAVA_HOME
# The only required environment variable is JAVA_HOME.  All others are
# set JAVA_HOME in this file, so that it is correctly defined on
 export JAVA_HOME=/usr/lib/jvm/java-1.6.0-openjdk

如何使JPS工作？