Hadoop 之 Configuration from Installation

Separating Configuration from Installation

In the example described above, the configuration files used by the Hadoop cluster all lie in the Hadoop installation. This can become cumbersome when upgrading to a new release since all custom config has to be re-created in the new installation. It is possible to separate the config from the install. To do so, select a directory to house Hadoop configuration (let's say /foo/bar/hadoop-config. Copy the hadoop-site.xml, slaves and hadoop-env.sh files to this directory. You can either set the HADOOP_CONF_DIR environment variable to refer to this directory or pass it directly to the Hadoop scripts with the --config option. In this case, the cluster start and stop commands specified in the above two sub-sections become
% $HADOOP_INSTALL/hadoop/bin/start-all.sh --config /foo/bar/hadoop-config and
% $HADOOP_INSTALL/hadoop/bin/stop-all.sh --config /foo/bar/hadoop-config.
Only the absolute path to the config directory should be passed to the scripts.

這個段落節錄於Hadoop office web site，可以點這個link連過去。

這個還蠻有用的，可以把Hadoop installation與configuration分開，記錄一下。