HADOOP_OPTS example in hadoop-env.sh breaks jsvc

Hi there,

The hadoop-env.sh script shipped with conf.empty and conf.pseudo suggests that HADOOP_OPTS might reasonably be set to "-server". If users do this, however, they'll run into

08/06/2011 10:08:35 18951 jsvc error: Invalid option -server
08/06/2011 10:08:35 18951 jsvc error: Cannot parse command line arguments

when they start the datanode.

The reason is that jsvc doesn't support the "-server" option. I've filed https://issues.apache.org/jira/browse/DAEMON-208 upstream for that support.

In the meanwhile, however, I recommend we remove the "suggestion" of using -server, and mention that the only valid flags are ones that exist in both jsvc 1.0.2 and standard java 1.6. I'll also note that the flags that jsvc support change over time. See http://www.apache.org/dist/commons/daemon/RELEASE-NOTES.txt for the latest release notes. Stuff like agentlib is now supported (though is not supported in the version of jsvc used by CDH3u0).

Here are the relevant places where this happens if you're tracing it:

etc/hadoop-0.20/conf.empty/hadoop-env.sh:
18:# if [ "$HADOOP_OPTS" == "" ]; then export HADOOP_OPTS=-server; else HADOOP_OPTS+=" -server"; fi
20:# Command specific options appended to HADOOP_OPTS when specified

etc/hadoop-0.20/conf.pseudo/hadoop-env.sh:
18:# if [ "$HADOOP_OPTS" == "" ]; then export HADOOP_OPTS=-server; else HADOOP_OPTS+=" -server"; fi
20:# Command specific options appended to HADOOP_OPTS when specified

usr/lib/hadoop-0.20/bin/hadoop:
424: $JAVA_HEAP_MAX $HADOOP_OPTS \
439: nohup $JAVA_EXEC -Dproc$COMMAND $JAVA_HEAP_MAX $HADOOP_OPTS -classpath "$CLASSPATH" $CLASS "$@" > "$_HADOOP_DAEMON_OUT" 2>&1 < /dev/null &