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techsupport:guides:ssh [2022/10/12 17:18] – [SSH Keys One Time Setup] Added advanced setup guide jlangetechsupport:guides:ssh [2023/09/07 15:35] (current) kjohns23
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-===== SoCS SSH Access =====+ ====== SoCS SSH Access ======
  
 +===== What is SSH =====
  
-==== The Basics ====+SSH is a program that allows you to log in to and run programs on a remote server. It is used in the School of Computer Science to allow access to our Linux Servers from your own computer, where you can edit, compile, and run code for your labs and assignments. SSH comes in two part - the client and the server.
  
-SSH is a program that allows you to log in to and run programs on a remote server. It is used in the School of Computer Science to allow access to our Linux Servers where you can edit, compile, and run code for your labs and assignments.+**The SSH Server:** The ssh server is a piece of software that runs on a remote computer and listens for connections from the SSH client.
  
-==== Accessing your SSH Client ====+**The SSH Client:** The SSH client runs on your own machine and allows you to connect to the server.
  
-To use SSH to connect to SoCS Servers, you will first need an SSH client. SSH is available on all three main operating systems.+===== Required Software ===== 
 + 
 +To use SSH to connect to SoCS Servers, you must have an SSH Client installed. SSH is available for the most common operating systems: Windows, MacOS, and Linux. 
 + 
 +==== Check if an SSH Client is Installed ====
  
 === Windows === === Windows ===
  
-A built in client is now available on Windows. You can access it by opening Windows Powershell. +A built in client is available on Windows, and can be accessed by opening the Windows Powershell application
  
 To check if ssh is installed, Open Windows Powershell, and type "ssh" followed by enter. You should see the following: To check if ssh is installed, Open Windows Powershell, and type "ssh" followed by enter. You should see the following:
  
-{{:techsupport:guides:ssh_windows_client.png?400|SSH Command Output}}+{{:techsupport:guides:ssh_windows_client.png?400|SSH Windows Command Output}}
  
-This client should be available by default, but if it is missing, follow the instructions in the Install SSH on Windows section below.+This client should be available by default, but if it is missing, follow the instructions in the [[ssh#Install SSH on Windows|Install SSH on Windows]] section.
  
 === Mac OS === === Mac OS ===
  
-The SSH client comes automatically installed as part of Mac OS. To access the ssh client, open the Terminal application.+The SSH client comes automatically installed as part of Mac OS. To access the ssh client, open the Terminal application, then type "ssh" followed by enterYou should see the following: 
 + 
 +{{:techsupport:guides:macsshtest.png?400|SSH Mac Command Output}}
  
 === Linux === === Linux ===
  
-The OpenSSH Client is available through your Package Manager on all major Linux Distributions. To install the client on a Debian/Ubuntu based distribution using Aptinstall the openssh-client package. To install on a RedHat based distribution using Yuminstall the openssh-clients package. Once installed you can access ssh through your distribution's terminal application.+The SSH client is usually installed on most Linux distributions. To check that it is installedopen your Terminal applicationthen type "ssh" followed by enterYou should see the following:
  
-==== SSH from Off-Campus ==== +===== Connecting to the SSH Server =====
-As of October 2022, using an ssh key is required to access SoCS Linux servers from off campus.+
  
 ==== Connecting to a Server ==== ==== Connecting to a Server ====
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 From Mac OS or Linux:\\ {{:techsupport:guides:ssh_user_linuxmac.png?400|}} From Mac OS or Linux:\\ {{:techsupport:guides:ssh_user_linuxmac.png?400|}}
  
-==== Common Problems and Errors==== +==== SSH from Off-Campus ==== 
-=== Time Out === +SSH connections from off campus are restricted by the campus firewall.
-== Problem == +
-After entering the ssh command there is a blinking cursor with no response, or the following error <code>ssh: connect to host linux.socs.uoguelph.ca port 22: Operation timed out</code>+
  
-== Solution == +  - **Preferred** SSH Connections are enabled off-campus while running the Campus VPN. Follow the [[https://uoguelphca.sharepoint.com/sites/ccs/SitePages/anyconnect-vpn-user-guide.aspx|VPN Setup Guide]] to installOnce the VPN is running, ssh to the server as you would from on campus. 
-If you are connecting from off campusthe most likely issue is that the CCS VPN is not runningEnsure that the VPN is enabled and try connecting againIf the VPN is running, or if you are connecting from on campus, it is possible the server is downContact [[help@socs.uoguelph.ca]] to report the possible issue.+  - Use SSH key based authentication to connect to Portkey from off campus, and then connect to the desired server. This is recommended only if you are unable to use the Campus VPNTo set this up, folow the [[techsupport:guides:sshkeyauth|SSH Key Authentication Guide]]
  
-=== Permission Denied === 
-== Problem == 
-Every time you enter your password, you receive the following error: <code>Permission denied, please try again.</code> 
  
-== Solution == 
-The most likely cause is that you are not specifying your username when trying to connect. If you type ''ssh linux.socs.uoguelph.ca'' as your command, it will automatically use your computer's user account name as the username. Make sure you specify your username with ''ssh username@linux.socs.uoguelph.ca''. 
  
 +===== Install the SSH Client =====
 ==== Install SSH on Windows ==== ==== Install SSH on Windows ====
  
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   * You can now open Windows Powershell and use SSH   * You can now open Windows Powershell and use SSH
  
-==== SSH Keys One Time Setup ====+==== Install SSH on Linux ====
  
-SSH Keys are an advanced feature that allow you to use a key to connect instead of using your password. This has the benefit of being both more secure, and more convenient to use. As of October 2022, SSH keys are required to access the SoCS servers from Off Campus. Regular password based login is still allowed from on campus. Please note that SSH may not be enabled on your Windows machine by default. Follow the topic in this article on how to install SSH before continuing with this guide.+=== APT ===
  
-To set up public key private key access to linux:+  * ''apt-get install openssh-client''
  
 +=== YUM ===
  
-== Advanced User Guide == +  * ''yum -y install openssh-clients''
  
-If you feel confident in your ability, below are the list of commands that you can execute to get your key onto the server while on campus. This guide is suited for students that can troubleshoot common Linux issues related to ssh and file movement. If you are not confident, continue to //Part A For all platforms// below for a more in-depth guide. 
  
-__Server-Side Setup__ +==== Common Problems and Errors==== 
-  ssh central-ID@linux.socs.uoguelph.ca +=== Time Out === 
-  cd ~ +== Problem == 
-  mkdir .ssh  +After entering the ssh command there is a blinking cursor with no response, or the following error <code>ssh: connect to host linux.socs.uoguelph.ca port 22: Operation timed out</code>
-  cd .ssh +
-  ls +
-  touch authorized_keys (if the file already exists, skip this step)+
  
-__Local Machine__ +== Solution == 
-  ssh-keygen -t ed25519 -C central-ID@linux.socs.uoguelph.ca  +If you are connecting from off campus, the most likely issue is that you are trying to connect to linux.socs.uoguelph.ca without the VPNYou should ensure you have followed the directions to install and run the Campus VPN.
-  scp ~/.ssh/id_ed25519.pub central-ID@linux.socs.uoguelph.ca:~/.ssh/ed25519.pub+
  
-__On linux.socs.uoguelph.ca__ +=== Permission Denied === 
-  cd ~/.ssh +== Problem == 
-  cat ed25519.pub >> authorized_keys +Every time you enter your password, you receive the following error: <code>Permission denied, please try again.</code>
-  exit+
  
-=== Part A For all platforms === +== Solution == 
-  - Have a passphrase (password) handy that you can remember. +The most likely cause is that you are not specifying your username when trying to connectIf you type ''ssh linux.socs.uoguelph.ca'' as your command, it will automatically use your computer's user account name as the usernameMake sure you specify your username with ''ssh username@linux.socs.uoguelph.ca''.
-  - Open a terminal window (or PowerShell for Windows) +
-  - Type ssh-keygen -t ed25519 -C yourusername@linux.socs.uoguelph.ca  at the command prompt +
-    - Press return to accept the default file locations for storing keys +
-    - Enter your passphrase when prompted (make sure you can remember it) +
-    - Enter the SAME passphrase again +
-  - In the same terminal window,  change to your .ssh directory. A foolproof way to do this is to first type cd followed by enter, then type cd .ssh +
-  - Type "more id_rsa.pub"  without the quotes +
-  - Copy the long string of text that begins with ssh-rsa and ends with yourusername@linux.socs.uoguelph.ca.  It will wrap across several lines. +
-  - Keep that text in the clipboard for the next step and go to Part B (either for on campus or off campus, depending on your location). +
- +
-=== Part B For all platforms (ON CAMPUS ONLY) === +
- +
-  - ssh to linux.scos.uoguelph.ca using your Central Login ID and password (use PowerShell on windows if you don't have a different client. On OS/X and linux just use a terminal) +
-  - Type "cd ~/.ssh" at the command prompt (without the quotes). +
-    * If you get an error ".ssh No such file or directory", type  "cd ~", then "mkdir .ssh", then type "cd .ssh", otherwise ignore this step. +
-  - Use your favourite command line editor (vimnano, emacs, etc.) to edit the authorized_keys file +
-    * i.e.  type 'nano authorized_keys' at the command line +
-    * Unless you've done this step once already, you will be creating this file.  it **MUST** be called authorized_keys +
-  - Paste in the long string of text that you copied to your clipboard in step A +
-  - Save the file. +
-  - Log out of the server. +
- +
-=== Part B For all platforms (OFF CAMPUS ONLY) === +
-  - Connect to NoMachine to facilitate the file transfer process. If you have not used NoMachine before, please reference our [[techsupport:guides:nomachine|guide to NoMachine here]]. NoMachine supports file transfer via scp and is our recommendation for off-campus students. +
-  - If you are unable to bring your private key to campus (via a laptop, removable storage device, etc.) and cannot transfer files via NoMachine, you must send your public key to [[help@socs.uoguelph.ca]]. Your public key will then be put into your home folder. This process may take up to a day to complete, so it is recommended to only use this option as a last resort. +
-  - Once the key has been added to the server, attempt to ssh from off campus using //ssh central-ID@portkey.uoguelph.ca//, agreeing to any prompts that you receive while connecting. You will be prompted to input the password you saved during the keygen creation here. +
-    * If ssh is not able to find your private keys file, you can include the -i flag to specify the location of your keys (ex. ssh //jdoe@uoguelph.ca -i ~/.ssh/id_rsa//+
-    * **NOTE: The portkey server is a jump server and has nothing installed.** You will not be able to run/compile code on this server - its sole purpose is to connect you to the main server cluster (linux.socs.uoguelph.ca). +
-  - After connecting to portkey, ssh again into central-ID@linux.socs.uoguelph.ca to ensure that your connection is successful. +
- +
-=== Part C For all platforms === +
-  - Open terminal window, or Powershell (Windows only) +
-  - ssh to portkey.socs.uoguelph.ca +
-  - You SHOULD be prompted for the passphrase you used in Part A, and then you should connect to our linux servers (//ssh central-ID@linux.socs.uoguelph.ca//). +
-  - This login method works for secure FTP programs too, such as filezilla, which will allow you to ftp files directly to your linux account. +
- +
-Once you have your ssh keys set up you will be able to use them to log in to any SoCS Linux server+
techsupport/guides/ssh.1665595086.txt.gz · Last modified: 2022/10/12 17:18 by jlange