Address @bkmgit's review comments

Author: tkphd

_episodes/11-connecting.md

@@ -212,8 +212,8 @@ is tedious and gets old very fast. This is where the [SSH Agent][ssh-agent]
 comes in.
 
 Using an SSH Agent, you can type your password for the private key once, then
-have the Agent remember for some number of hours or until you log off. Unless
-some nefarious actor has physical access to your machine, this keeps the
+have the Agent remember it for some number of hours or until you log off.
+Unless some nefarious actor has physical access to your machine, this keeps the
 password safe, and removes the tedium of entering the password multiple times.
 
 Just remember your password, because once it expires in the Agent, you have to

_episodes/14-modules.md

@@ -9,7 +9,7 @@ objectives:
 - "Understand how the module mechanism interacts with the shell."
 keypoints:
 - "Load software with `module load softwareName`."
-- "Unload software with `module purge`"
+- "Unload software with `module unload`"
 - "The module system handles software versioning and package conflicts for you
   automatically."
 ---
@@ -153,7 +153,7 @@ the manipulation of environment variables like `$PATH`. There
 is usually little or no data transfer involved.
 
 The module loading process manipulates other special environment
-variables as well, including variables that influence where the 
+variables as well, including variables that influence where the
 system looks for software libraries, and sometimes variables which
 tell commercial software packages where to find license servers.
 

_episodes/15-transferring-files.md

@@ -8,24 +8,23 @@ objectives:
 - "Be able to transfer files to and from a computing cluster."
 keypoints:
 - "`wget` and `curl -O` download a file from the internet."
-- "`scp` transfer files to and from your computer."
+- "`scp` and `rsync` transfer files to and from your computer."
 - "You can use an SFTP client like FileZilla to transfer files through a GUI."
 ---
 
-Computing with a remote computer offers very limited utility if we cannot 
-get files to or from the cluster. There are several options for 
-transferring data between computing resources, from command line 
-options to GUI programs, which we will cover here.
+Performing work on a remote computer is not very useful if we cannot get files
+to or from the cluster. There are several options for transferring data between
+computing resources using CLI and GUI utilities, a few of which we will cover.
 
 ## Download Files From the Internet
 
 One of the most straightforward ways to download files is to use either `curl`
 or `wget`. One of these is usually installed in most Linux shells, on Mac OS
-terminal and in GitBash. Any file that can be downloaded in your web browser 
-through a direct link can be downloaded using `curl -O` or `wget`. This is a 
-quick way to download datasets or source code. 
+terminal and in GitBash. Any file that can be downloaded in your web browser
+through a direct link can be downloaded using `curl -O` or `wget`. This is a
+quick way to download datasets or source code.
 
-The syntax for these commands is: `curl -O https://some/link/to/a/file` 
+The syntax for these commands is: `curl -O https://some/link/to/a/file`
 and `wget https://some/link/to/a/file`. Try it out by downloading
 some material we'll use later on, from a terminal on your local machine.
 
@@ -53,7 +52,7 @@ or
 
 To copy a single file to or from the cluster, we can use `scp` ("secure copy").
 The syntax can be a little complex for new users, but we'll break it down.
-The `scp` command is a relative of the `ssh` command we used to 
+The `scp` command is a relative of the `ssh` command we used to
 access the system, and can use the same public-key authentication
 mechanism.
 
@@ -203,6 +202,34 @@ A trailing slash on the target directory is optional, and has no effect for
 > {: .language-bash}
 {: .callout}
 
+All file transfers using the above methods use SSH to encrypt data sent through
+the network. So, if you can connect via SSH, you will be able to transfer
+files. By default, SSH uses network port 22. If a custom SSH port is in use,
+you will have to specify it using the appropriate flag, often `-p`, `-P`, or
+`--port`. Check `--help` or the `man` page if you're unsure.
+
+> ## Change the Rsync Port
+>
+> Say we have to connect `rsync` through port 768 instead of 22. How would we
+> modify this command?
+>
+> ```
+> {{ site.local.prompt }} rsync test.txt {{ site.remote.user }}@{{ site.remote.login }}:
+> ```
+> {: .language-bash}
+>
+> > ## Solution
+> >
+> > ```
+> > {{ site.local.prompt }} rsync --help | grep port
+> >      --port=PORT             specify double-colon alternate port number
+> > See http://rsync.samba.org/ for updates, bug reports, and answers
+> > {{ site.local.prompt }} rsync --port=768 test.txt {{ site.remote.user }}@{{ site.remote.login }}:
+> > ```
+> > {: .language-bash}
+> {: .solution}
+> {: .challenge}
+
 ## Transferring Files Interactively with FileZilla
 
 FileZilla is a cross-platform client for downloading and uploading files to and

index.md

@@ -23,8 +23,8 @@ By the end of this workshop, students will know how to:
 
 * Identify problems a cluster can help solve
 * Use the UNIX shell (also known as terminal or command line) to
-connect to a cluster.
-* Download files from the internet directly on a cluster.
+  connect to a cluster.
+* Transfer files onto a cluster.
 * Submit and manage jobs on a cluster using a scheduler.
 * Observe the benefits and limitations of parallel execution.