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Note there are 2 Linux Labs required in LM2. This lab/Web page is LL2a and requires 2 screenshots. LL2b is a separate lab (Web page) located below LL2a in the Linux Lab menu above.
HVCC AcadNX Server accounts are refreshed hourly during registration.
Please note: Comp Sci (CS) is a precise discipline requiring discrete understanding and exacting attention to detail. In LM1 I presented that students new to CS sometimes struggle with the exacting terminology where the words look familiar (e.g. gateway, reference, etc.) but have precise meanings in CS. This is especially the case with Linux as a listing is not the same as a long listing or a complete listing. To this extent, you will need to reread the Linux Labs and the assigned readings throughout the course with exacting attention to detail as future labs will draw from and extend past material. This is what is required to succeed in this discipline.
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Required Reading
Linux Command Line Text by Shotts => Chapter 1.1 and please return and try some Linux commands in Chapter 1.1 after you get connected to AcadNX. Note some commands like ls will not show you any files as you have not created any files in your user space yet.
The passwd command is located at the tail end of chapter 9. Recall you can search this pdf textbook that opens in a browser window using ctrl-f on Windows and command-f on Mac so you can search for the occurrence of the “passwd” command. (you, of course, can also search GNU/Linux Basic Operating System using the same method).
*Note, you may have to search (e.g. Google) to read additional background material and see examples to get used to the Linux environment and fully understand the material. As an example, you could Google “Ubuntu password command” or “Linux password command examples” to see the Linux password command syntax and semantics (note if the words syntax and semantics are unfamiliar, please look these up as well).
HVCC Multi-factor authentication
Note: the College has just added multi-factor authentication to AcadNX (similar to what is required for HVCC email access where you supply a code you receive via text/etc.). Directions are below if unfamiliar and please note some students and I have experienced SMS delivery delays so please be patient with the delivery of the text code: https://hvcc.teamdynamix.com/TDClient/1967/Portal/KB/ArticleDet?ID=143794
HVCC Acadnx Intro
Here we will connect to the HVCC acadnx Ubuntu server with SSH and following this we will become acquainted with the Command Line Interface (CLI) Linux Labs today and in subsequent weeks.
First, note that the HVCC acadnx server is an Ubuntu Linux server so we will be working in a client-server environment (your computer is the client and the server is the HVCC AcadNX Ubuntu server). SSH is short for “secure shell” and will provide us with a secure Terminal or Command Line Interface (CLI) connection to the Ubuntu OS on the AcadNX server. (This security is obtained through encryption and you will also see the closely related term cipher).
SSH
Developed by SSH Communications Security Ltd., Secure Shell is a program to log into another computer over a network, to execute commands in a remote machine, and to move files from one machine to another. It provides strong authentication and secure communications over insecure channels using public-key encryption. (It is a replacement for rlogin, rsh, rcp, and rdist.) SSH protects a network from attacks such as IP spoofing, IP source routing, and DNS spoofing and also works with RSA authentication.
When using ssh’s slogin (instead of rlogin) the entire login session, including transmission of password, is encrypted; therefore it is almost impossible for an outsider to collect passwords. SSH is available by default in network OSs like Macintosh, Linux, and Unix and ssh clients like PuTTY or KiTTy are available for Windows (It can be installed in OS/2 as well). An attacker who has managed to take over a network can only force ssh to disconnect. The attacker cannot playback the traffic or hijack the connection when encryption is enabled. You will learn this is network confidentiality and again, to demonstrate the precise nature of our terminology, if I had asked you what confidentiality was prior to providing you with this Comp Sci definition, would you have answered it correctly as everyone surely knows the meaning of confidentiality in everyday language.
A very nice SSH introduction is located here, minimally please read the top “What is SSH” portion: “http://support.suso.com/supki/SSH_Tutorial_for_Linux.
HVCC acadnx usernames & passwords
username – a username is your unique account name and later on, we will learn that it is recorded in the password file. AcadNX usernames are standard HVCC usernames (e.g. a-student, j-doe, j-smith, etc and note the username may have numbers as well in accord with your HVCC username e.g. a-student32, j-doe12, etc.)
Note that usernames are easily identifiable as they are the first component in an email address which has the convention “username@domain” or as an example: j.looby@hvcc.edu
password – your initial AcadNX password will be your username minus the hyphen (e.g. astudent or astudent32 in the corresponding examples above). You will change this after you connect to the Ubuntu Server. Note some Unix/Linux systems will not display your password as you type it so please do not be alarmed if you do not see your text as you type your password.
Ok so now let’s get connected. Below are instructions and videos of my installation on Mac and Windows. If you are a Linux user you will follow the Mac SSH instructions as Mac is Linux/Unix based and uses the terminal (Mac and Linux are Network Operating Systems so networking is built-in). While you will choose your appropriate platform (Mac or Win) instructions to get connected to the HVCC acadnx Ubuntu server, please read both sections and watch both videos as multi-platform understanding is now your professional responsibility. After you have completed your connection you will continue with the “acadnx connection screenshot” assignment instructions and submit/upload your screenshot in Blackboard LM2 LL2a assignment area.
Windows screenshot, MS Word paste and PDF save demonstration video below and instructions for the Windows Snipping Tool is here: Windows Snipping Tool
Mac OSX screenshots are straightforward and provide more control by using the Command + Shift + 4 keys simultaneously and then highlighting the area you want to capture. Following this, the screenshot is saved as an image in your Downloads folder so you can copy and paste it from there. Full Mac OSX screenshot documentation here: https://support.apple.com/en-us/HT201361
Mac OSX/Linux SSH Connection
Mac OSX and Linux are network OSs and as such have a built in terminal. Mac OSX Terminal instructions here and in the video below (Linux instructions are nearly identical and the terminal is normally located in the dock but Linux distributions can vary so you may have to open the Application menu/list to find the terminal).
1. Open Applications => Utilities => Terminal
If the Applications icon is not in the dock, open Finder and you should see it in the left or main center panel. If it is not visible in Finder, open Finder, choose “Finder” in the main menu across the top of the screen, choose “Preferences” and then choose the “Sidebar” tab. In the Sidebar tab check the box to show “Applications” in finder.
2. In the Terminal, on the command line enter the command: ssh username@acadnx.hvcc.edu noting that you replace username with your hvcc username (for me, if I was a student this would be: ssh j-looby@acadnx.hvcc.edu).
3. You may have to choose yes to accept the certificate/fingerprint/host key (you may trust HVCC server certificate).
4. Enter your password with the format explained above (for me this would be jlooby) and press enter/return. Note that you may or may not see the characters as you type your password.
5. Note at the end of the video I reference the OpenNX Virtual Desktop Interface or VDI but we no longer use that VDI due to instability on some platforms. (OpenNX was a GUI for the AcadNX Ubuntu system and distinct from our HVCC Academic Computing Environment or ACE VDI). In other words, you can ignore the reference to OpenNX.
A lecture capture of this Mac process is here:
Chrome Browser SSH Plugin/Extension Option
Here is another SSH connection solution. In a nutshell, search for, download, and install the Chrome SSH Plugin/Extension or Firefox SSH Plugin and then connect very similarly to the Mac OSX/Linux process (and to that extent please see Mac OSX/Linux SSH connection first). Chrome video below.
If you are using Chrome OS, there is the App version but I have not tested this since I don't have a Chromebook. All other platforms should use the extension version instead. The extension version can be found here: https://chrome.google.com/webstore/detail/iodihamcpbpeioajjeobimgagajmlibd
Chromebook Users
Please download and try Secure Shell Extension. If that doesn’t work I’m afraid you’ll have to use a HVCC computer and PuTTy.
HVCC ACE Computers (i.e. on-campus computers)
PuTTy is installed on all HVCC Academic Computing Environment (ACE) Windows machines in labs and classrooms so you can perform the Linux Labs on campus.
On HVCC ACE Computers you will find PuTTy and WinSCP in the SSH folder (Start => All Programs => SSH => PuTTy) or as a separate PuTTy item in the main start menu. You will not have to install it as you simply need to follow the connection Windows OS SSH Connection instructions below (note you should also be able to install the SSH Chrome extension in your ACE Chrome instance).
MS Windows OS SSH Connection
MS Windows is not a network OS so SSH is not “built into” the Windows OS as it is in Mac/Linux which are both Network Operation System (NOS). To use SSH on Windows there are several SSH options but we will use PuTTY or KiTTy (KiTTy is an updated version of PuTTy with the exact same interface). PuTTY (/ˈpʌti/) is a free and open-source terminal emulator. Putty is available on HVCC ACE computers (classes & labs) in the Start Menu SSH folder so there is no need to download PuTTY when working on campus.
PuTTY installation instructions:
1. Open a Browser, search for “PuTTY download”
2. Download PuTTY (putty.exe) to your desktop from either putty.org or microsoft’s download store (link may change but it is presently here: https://www.microsoft.com/en-us/p/putty-unofficial/9n8pdn6ks0f8?activetab=pivot:overviewtab). (Again, PuTTY is available on campus computers so you just need to open Start => All Programs => find and launch PuTTY if on campus). Important: please read the download page and I recommend you don’t allow the site to download anything other than PuTTy. Sometimes less ethical sites will have the box checked to download other software by default.
Open, install and run PuTTy
(Windows 8 users may have to choose “More Info” which will bring up a screen allowing them to “Run Anyway”)
1. In the Hostname (or IP Address) enter: acadnx.hvcc.edu
2. Make sure “SSH” radio button box is selected.
3. If necessary, choose yes and accept the certificate/host key (meaning you may trust the HVCC server).
4. Enter your username and password using the conventions above when prompted and press enter/return. Note that you may or may not see the characters as you type your password as this is another security mechanism so that no one can be watching.
=> If PuTTy fails to connect to AcadNX (due to a failed/outdated key exchange). Please download and run KiTTy with the exact same above and below video instructions and leave the KiTTy download .exe on your desktop for easy access. https://kitty.en.lo4d.com/download
***Note you can also use the Browser plugin if PuTTy fails***
A lecture capture of this process is here:
iPhone/Android
I have been alerted there is a good mobile ssh client called Termius but should students choose this option they will need to research how to take a screenshot on their mobile device and send to their computer so that they can insert the screenshots in a document and save as pdf. Link is here: https://termius.com
Assignment – Exercise 1a (of LL2a): SSH AcadNX connection screenshot
1. Please research how to take a screenshot for your particular platform as presented above (i.e. Google Windows Screenshot or Mac Screenshot and/or seek out YouTube videos).
2. Take a screenshot of your Terminal/Shell displaying your SSH connection (i.e. your Mac Terminal or PuTTY Terminal with the Linux prompt showing your username in the prompt). Please make sure the Linux prompt is in the screenshot (i.e. not the 2-factor/multi-factor authentication).
3. Paste the screenshot image into a word processing document and please provide the title “1a SSH acadnx connection” above the screenshot image. Note you may want to hit “Return” several times so that you can add an image title prior to pasting it. After you paste your screenshot please insert a page break so that the next image can be pasted on a fresh page. Note you will do this for all subsequent labs and screenshots providing the exercise number and title and separating exercises, 1 exercise to a page.
4. You will save this file as a .pdf (found in the “Save As” menu of your word processor) and name this file using the following convention: LastnameFirstnameLL2a (for me this would be LoobyJamesLL2a). Your word processor will affix the .pdf extension when you choose “Save As PDF”.
Note you will submit a single .pdf file with all the lab’s screenshots pasted and titled into the .pdf. For this assignment, you will have the 1a SSH acadnx connection screenshot and 1b password change screenshot detailed below saved in this single pdf. The 1a SSH acadnx connection and 1b password change headings must precede the screenshots to receive credit. Note, this is both required and very important since we must learn to follow directions and Code to Standards as this will be required throughout your professional careers. To put this in context, if you submit a resume, bid, quote, etc and your submission is not in the prescribed format, your resume, bid, quote etc. will be rejected.
BTW – why .pdf? Because PDFs open in a browser window without needing to open the associated application and this was your first Web Accessibility lesson.
Note if you do not have a word processor or a word processor that saves files in .pdf format I recommend you download Open Office – www.openoffice.org
Password Reset
Ok, so we always think about security first so we need to change our password. When we change our password in Linux (either in a SSH/PuTTY Terminal) we will use our new password to login to the system from this point on.
Changing your password is covered in the text on page 106 (required reading textbook link at top of page).
Additional information on setting Linux passwords can be found online so please Google: “Linux Password Command” or even “Changing Linux Password”
Open a Terminal either through SSH/PuTTY if you closed your session and change your password using the Linux passwd command. I recommend you use your main HVCC password to maintain consistency.
NOTE: If you forget the password you just changed, you will need to email dlhelp@hvcc.edu and ask for them (ITS) to reset your password to the default (i.e. your username without the hypen).
Exercise 1b: password change screenshot
1. Please take a screenshot of your password reset and paste the screenshot into your document on a new page (i.e. insert a page break and add to LastnameFirstnameLL2). Please be sure to add the “1b password change screenshot” heading to the screenshot and please be sure this is on a new page in your document. Also, if possible, please try to make it readable or several lines/carriage returns above the screenshot.
2. Submit your single LastnameFirstnameLL2a.pdf document with both screenshots to the Blackboard LM2 assignment folder (BB => LM2 => LL2a Submission => Attach File => Browse My Computer).
2. Logout of SSH by issuing the “logout” command at the terminal prompt (i.e. type logout at the prompt).
3. I know you know this but… please save your files on your computer should something go wrong.
Assignment Submission: Submit your single LastnameFirstnameLL2a.pdf document with the screenshots and exercise headings in Blackboard. Please make sure your file is named properly as in CS/IT, failure to follow explicit directions could cause you to lose a prospective job or contract. Please logout or quit your CLI/Terminal and this is done by issuing the logout command at the terminal prompt.
Another demonstration leading up to LL2b
Here is a quick demonstration of the AcadNX Linux environment and some of the commands we will use beginning next week. I provide it here because it is good to see the environment in action prior to your LL2b readings. Please note I am not covering the lab in this video as I am just highlighting a few things to get everyone started and illustrate the detail with which you must be reading (and rereading) the material and note you will not see anything with the generic ls as you have not created any files or directories to date.
Getting help from your faculty
First, please provide an appropriate email subject heading per LM1 directions (your name, section and issue). I need to know your platform (Mac, Windows, Chromebook), operating system version, whether you’re running anti-virus/VPN, etc. Please be as specific as possible and include the precise step you’re having problems along with screenshots of your Putty/login screen with Host Name and the resulting screen when you choose open. Please understand without complete accurate information I can only guess at what is going on and we do not guess in Comp Sci. Please note we need to follow this process in the future (i.e. exact step and screenshots)
Note the above is highly instructive as we are learning about what is required for IT/Help Desk support as we can only assess the situation with complete accurate information (similar to our computing systems that don’t accept ambiguity). We need complete information to accurately assist.
Lastly please note you may need to use your “administrator account to utilize administrative authorization” to install software. Every system/platform is different so you need to research this yourself but it is straightforward using the discrete terminology above coupled with your OS and possibly “install software” in a Google or YouTube search (e.g. software installation administrator privileges Windows 7).
Help and FAQ
Hi all, if your PuTTY session times out, please make sure you check the box for TCPKeepAlive in PuTTY configuration.
If you don’t have a word processor you can use Open Office and its “Writer” application (just Google “Open Office Download”) and there are many Open Office tutorials on YouTube. You could also purchase MS Office with an educational discount (last I saw this was $9.95) and instructions are here: https://www.youtube.com/watch?v=KxPiXEu2n3I
Lastly – Note if you explore using the Linux “ls” command on your system you will not see my directory structure as your directory structure is empty at this point (ls -a will show you the hidden files present). Please read LL1, LL2a, LL2b content concerning the password the Linux passwd command if necessary (You can also Google “Linux passwd”). Note, you will only gain command of this material through continuing sustained research and practice.
Thank you,
Prof Looby,