On Sep 10, 2014, at 10:14 AM, Sangjin Lee <[email protected]> wrote:
> if HADOOP_USER_CLASSPATH_FIRST is
> set and the user provides his/her version of *-site.xml through
> HADOOP_CLASSPATH, the user would end up trumping the hadoop configuration.
> And I believe this behavior is preserved after Allen's changes
> (HADOOP-9902).
>
I'd be surprised if 9902 changed this behavior, especially given that
HADOOP_CONF_DIR is added fairly quickly to the CLASSPATH and
HADOOP_USER_CLASSPATH is processed last or near last.
> Is this an intended behavior? What I'm not sure of is whether we expect the
> client to be able to override the site.xml files the hadoop configuration
> provides. If that is true, then it is working as desired. If not, we'd need
> to fix this behavior.
>
> Thoughts?
>
Users have always been able to override the *-site.xml files via java
properties, jobconf/etc, pointing HADOOP_CONF_DIR to somewhere else, or
providing --conf flags to shell commands. In other words, this isn't new
behavior, but provides yet another option to override the provided settings.
