Improving style in the INSTALL file

mafju · mafju · commit 0d73d4235e8a · 2012-08-23T09:37:13.000+02:00
diff --git a/INSTALL.md b/INSTALL.md
@@ -1,26 +1,26 @@
-In order to run the application you have to have Cloudera's Hadoop installed. The steps of installation procedure are described below.
+In order to run the application, you need to have Cloudera's Hadoop installed. The steps of the installation procedure are given below.
 
 Hadoop: installation and configuration
 ======================================
-Warning: Because of a bug in the Oozie version provided with Cloudera's Hadoop (which is removed in the version available in the source code repository), **you have to have (Oracle) Java JDK 1.6 installed**. This version of Oozie does not work with JDK 1.7.
+IMPORTANT: Because of a bug in the Oozie version provided with Cloudera's Hadoop (by the way: this bug is removed in the version of Oozie available in the source code repository), **you need to have Oracle Java JDK 1.6 installed**. Oozie **does not** work with JDK 1.7.
 
 ---
 
-Install Cloudera Hadoop CDH4 with MRv1 in accordance with the instructions given in [Cloudera CDH4 intallation guide](https://ccp.cloudera.com/display/CDH4DOC/CDH4+Installation+Guide) , to be more specific:
+The instructions below show how to install Cloudera Hadoop CDH4 with MRv1 in accordance with the instructions given in [Cloudera CDH4 intallation guide](https://ccp.cloudera.com/display/CDH4DOC/CDH4+Installation+Guide).
 
-Hadoop can be run in one of three modes:
+It is important to know that Hadoop can be run in one of three modes:
 
 - **standalone mode** - runs all of the Hadoop processes in a single JVM which makes it easy to debug the application. 
-- **pseudo-distributed mode** - runs a full-fledged Hadoop on your local computer
-- **distributed mode** - runs on a cluster consisting of many nodes/hosts
+- **pseudo-distributed mode** - runs a full-fledged Hadoop on your local computer.
+- **distributed mode** - runs the application on a cluster consisting of many nodes/hosts.
 
-Below we will show how to install Hadoop initially in pseudo-distributed mode but we will be able to switch between standalone and pseudo-distributed modes.
+Below we will show how to install Hadoop initially in the pseudo-distributed mode but with a possibility to switch between the standalone and the pseudo-distributed mode.
 
-Install Hadoop in pseudo-distributed mode, see  [Cloudera CDH4 pseudo distributed mode installation guide](https://ccp.cloudera.com/display/CDH4DOC/Installing+CDH4+on+a+Single+Linux+Node+in+Pseudo-distributed+Mode)
+Hadoop: installation
+--------------------
+Installing Hadoop in pseudo-distributed mode (based on [Cloudera CDH4 pseudo distributed mode installation guide](https://ccp.cloudera.com/display/CDH4DOC/Installing+CDH4+on+a+Single+Linux+Node+in+Pseudo-distributed+Mode)) in case of 64-bit Ubuntu 12.04:
 
-In case of Ubuntu 12.04:
-
-- create new file `/etc/apt/sources.list.d/cloudera.list` with contents:
+- create a new file `/etc/apt/sources.list.d/cloudera.list` with contents:
 
 		deb http://archive.cloudera.com/cdh4/ubuntu/precise/amd64/cdh precise-cdh4 contrib
 		deb-src http://archive.cloudera.com/cdh4/ubuntu/precise/amd64/cdh precise-cdh4 contrib
@@ -37,24 +37,27 @@ In case of Ubuntu 12.04:
 			
 		sudo apt-get install hadoop-0.20-conf-pseudo
 			
-- next, follow the steps described in the Cloudera's guide for installing Hadoop in pseudo-distributed mode starting from the step "Step 1: Format the NameNode." This is available at [Cloudera CDH4 pseudo distributed mode installation guide - "Step 1: Format the Namenode"](https://ccp.cloudera.com/display/CDH4DOC/Installing+CDH4+on+a+Single+Linux+Node+in+Pseudo-distributed+Mode#InstallingCDH4onaSingleLinuxNodeinPseudo-distributedMode-Step1%3AFormattheNameNode.).
+- next, follow the steps described in the Cloudera's guide to installing Hadoop in the pseudo-distributed mode starting from the step "Step 1: Format the NameNode." This is available at [Cloudera CDH4 pseudo distributed mode installation guide - "Step 1: Format the Namenode"](https://ccp.cloudera.com/display/CDH4DOC/Installing+CDH4+on+a+Single+Linux+Node+in+Pseudo-distributed+Mode#InstallingCDH4onaSingleLinuxNodeinPseudo-distributedMode-Step1%3AFormattheNameNode.).
 		
----
+Hadoop: after install
+---------------------
 
-You can **switch between standalone and pseudo-distributed configurations** (or others) of Hadoop using the `update-alternatives` command, e.g.:
+### Switching between Hadoop modes
+When you have Hadoop installed, you can **switch between standalone and pseudo-distributed configurations** (or other kinds of configurations) of Hadoop using the `update-alternatives` command, e.g.:
 
-- `update-alternatives --display hadoop-conf` for list of available configurations and information which is the active one 
+- `update-alternatives --display hadoop-conf` for list of available configurations and information which one is currently active
 - `sudo update-alternatives --set hadoop-conf /etc/hadoop/conf.empty` to set the active configuration to `/etc/hadoop/conf.empty` which corresponds to Hadoop standalone mode.
 
-You can view the web interfaces to the following services using the addresses:
+### Web interfaces
+You can view the web interfaces to the following services using appropriate addresses:
 
 - **NameNode** - provides a web console for viewing HDFS, number of Data Nodes, and logs - [http://localhost:50070/](http://localhost:50070/)
 	- In the pseudo-distributed configuration, you should see one live DataNode named "localhost".
-- **JobTracker** - allows viewing and running completed and failed jobs with logs - [http://localhost:50030/](http://localhost:50030/)
+- **JobTracker** - allows viewing the completed, currently running, and failed jobs along with their logs - [http://localhost:50030/](http://localhost:50030/)
 
 Oozie: installation and configuration
 -------------------------------------
-Based on [Cloudera CDH4 Oozie installation guide](https://ccp.cloudera.com/display/CDH4DOC/Oozie+Installation#OozieInstallation-ConfiguringOozieinstall)
+The description below is based on [Cloudera CDH4 Oozie installation guide](https://ccp.cloudera.com/display/CDH4DOC/Oozie+Installation#OozieInstallation-ConfiguringOozieinstall).
 
 - Install Oozie with
 
@@ -65,7 +68,7 @@ Based on [Cloudera CDH4 Oozie installation guide](https://ccp.cloudera.com/displ
 		sudo -u oozie /usr/lib/oozie/bin/ooziedb.sh create -run
 	
 
-	- this should result in a similar output:
+	- this should result an output similar to this one:
 
 			Validate DB Connection
 			DONE
@@ -82,7 +85,7 @@ Based on [Cloudera CDH4 Oozie installation guide](https://ccp.cloudera.com/displ
 
 			The SQL commands have been written to: /tmp/ooziedb-8221670220279408806.sql
 
-- Install ExtJS version 2.2 library:
+- Install version 2.2 of ExtJS library:
 	- download the zipped library from [http://extjs.com/deploy/ext-2.2.zip](http://extjs.com/deploy/ext-2.2.zip)
 	- copy the zip file to `/var/lib/oozie` end extract it there
 - Install Oozie ShareLib:
@@ -98,15 +101,15 @@ Based on [Cloudera CDH4 Oozie installation guide](https://ccp.cloudera.com/displ
 
 		sudo service oozie start
 
-- Check Status of the server:
-	- from command-line:
+- Check the status of the server:
+	- From command-line:
 
 			oozie admin -oozie http://localhost:11000/oozie -status
 	
-	This should be printed out:
+	as a result, should be printed out:
 
 			System mode: NORMAL
 	
-	- Through a webpage - use a web browser to open: [http://localhost:11000/oozie/](http://localhost:11000/oozie/)
+	- Through a webpage - use a web browser to open a webpage at the following address: [http://localhost:11000/oozie/](http://localhost:11000/oozie/)
 
-If you want to check if Oozie correctly executes workflows, you can run some example workflows as described in [Cloudera Oozie example workflows](http://archive.cloudera.com/cdh4/cdh/4/oozie/DG_Examples.html). Note that contrary to what is written there, the Oozie server is not available at `http://localhost:8080/oozie` but at `http://localhost:11000/oozie` address
+If you want to check if Oozie correctly executes its workflows, you can run some of the example workflows provided with Oozie as described in [Cloudera Oozie example workflows](http://archive.cloudera.com/cdh4/cdh/4/oozie/DG_Examples.html). Note that contrary to what is written there, the Oozie server is not available at `http://localhost:8080/oozie` but at `http://localhost:11000/oozie` address.
