Merge remote-tracking branch 'origin/chef-tutorial'

cloudlab-chef-tutorial.scrbl

@@ -35,7 +35,7 @@ In the process of taking this tutorial, you will learn to:
 
 This tutorial will demonstrate how experiments can be managed on @(tb), as well as show
 how experiment resources can be administered using Chef. 
-By following the instructions provided below, you will learn how to take advatage of the powerful features of Chef
+By following the instructions provided below, you will learn how to take advantage of the powerful features of Chef
 for configuring multi-node software environments.
 The exercises included in this tutorial are built around simple but realistic 
 configurations. In the process of recreating these configurations on nodes running 
@@ -357,7 +357,7 @@ components that we don't use in this tutorial, it is worth noting the following:
 
   @item{@bold{Recipes}, shown next to cookbooks on the workstation, are the "building blocks" from which
   cookbooks are assembled. Recipes can be viewed as individual scripts accomplishing specific
-  fine-grained tasks, such as create a user, install a package, clone a respository, configure a network interface, etc.
+  fine-grained tasks, such as create a user, install a package, clone a repository, configure a network interface, etc.
   Cookbooks, which include one or more recipes, are responsible for "bigger" tasks: 
   install and configure a database, install and run a web server, and so on.}
   
@@ -715,7 +715,7 @@ executed as @italic{root}). Run the commands described below in that shell.
 
 @itemlist[#:style 'ordered
   @instructionstep["Add a role to the head's run list"]{
-    Issues the command in bold (the rest is the expected output):
+    Issue the command in bold (the rest is the expected output):
 
     @verbatim{@bold{knife node run_list add head "role[apache2]"}                                              
     head:                                                                                                  
@@ -725,7 +725,7 @@ executed as @italic{root}). Run the commands described below in that shell.
     }
   }
   @instructionstep["Add two roles to the node-0's run list"]{
-    Run the two @code{knife} commands listed below to assign two roles to @tt{node-0}:
+    Run the two @code{knife} commands listed below (also on @tt{head}) in order to assign two roles to @tt{node-0}:
 
     @verbatim{@bold{knife node run_list add node-0 "role[apache2]"}
     run_list:                                                                                            
@@ -788,6 +788,11 @@ executed as @italic{root}). Run the commands described below in that shell.
     of replacing @code{pdsh}, the Parallel Distributed Shell utility, that is often used on computing clusters.
 
     The output that is similar to the one above indicates that both @code{apache2} web servers are running. 
+    The command that you have just issued uses @code{netstat}, a command-line tool that displays network connections, 
+    routing tables, interface statistics, etc. Using @code{knife}, you have run 
+    @code{netstat} in combination with a Linux pipe and a @code{grep} command 
+    for filtering output and displaying the information only on the port @code{8080}.
+    
   }
   @instructionstep["Check benchmarking results on node-0"]{
 
@@ -825,7 +830,7 @@ executed as @italic{root}). Run the commands described below in that shell.
     for one of its attributes.
 
     In the console, click on the Policy tab at the top of the page, choose ``Roles'' in the panel on the left,
-    and select ``apachebench'' in the displayed list or roles.
+    and select ``apachebench'' in the displayed list of roles.
     Select the Attributes tab in the middle of the page.
     At the bottom of the page, you should now see 
     a panel called ``Override Attributes''. Click the ``Edit'' button inside that panel:  
@@ -915,7 +920,7 @@ are available for many common administrative needs. You can refer to the
 @link["https://docs.chef.io/resources.html#resources"]{list of supported Chef resources}
 and see examples of how they can be used.  
 
-Another item that is worth mentioning in is the  
+Another item that is worth mentioning is the  
 ``@code{ignore_failure true}'' attribute used in some of the resources.
 It allows the recipe to continue execution even when something does not
 go as expected (shell command fail, necessary files do not exist, etc.).