How-to: Connect via SSH (PuTTY, macOS terminal)

Owned by Karker, Nicholas
Last updated: Nov 21, 2024 by Albers, Michael W
5 min read

NOTE: If you are off campus you need to connect to the VPN prior to starting the process below.  Each time you ssh in, you will need to be on the VPN first.

Action

This guide details how to connect to batch via SSH from a windows or mac machine. batch is only accessible from within the University at Albany network. To connect from an external network, you must use the VPN. Please read more at the Remote Access page.

To spawn a terminal session, you can use PuTTY and VcXsrv on Windows. On mac, you can use your terminal with XQuartz for X11 Forwarding and a terminal session. More details below. 

Instructions

Windows

Several options are available for connecting to research systems from a windows computer. This documentation will focus on PuTTY and VcXsrv for X11 forwarding. 

VcXsrv

X11 is a communication protocol for "forwarding" graphics from one machine to another. In order to display graphics or run programs interactively with PuTTY, VcXsrv must be running as well. To start using VcXsrv

  1. Download and install VcXsrv

  2. From the start menu, search for XLaunch

  3. Select the configuration options that you would like, here we use "Multiple windows", "Start no client", and the default "Extra settings" parameters

  4. After clicking finish, you will see the XLaunch logo in the Task bar (note that you may have to expand it)


  5. Now, you are all set for PuTTY with X11 fowarding

 

 

PuTTY

PuTTY is an SSH and telnet client, developed originally by Simon Tatham for the Windows platform. PuTTY is open source software that is available with source code and is developed and supported by a group of volunteers. It can be downloaded here and is commonly used alongside VcXsrv for X11 Forwarding.

Note that while connected via SSH and PuTTY, if your internet connection is interrupted, all running code will be exited. To avoid this, we recommend using Screen or Tmux to "detatch" terminal sessions. For more information, please see How-to: Using screen or tmux to preserve a Linux terminal session

  1. Download and install PuTTY (https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html)

  2. Make sure you have XLaunch running (see above)

  3. Find PuTTY in the start menu, and start the application

  4. For host name, you make connect to a number of resources (e.g., head.its.albany.edu, headnode7.arcc.albany.edu, lmm.its.albany.edu), here we will connect to the headnode head.its.albany.edu

    1. Enter head.its.albany.edu and port 22 as shown below

    2. Next click on Connection -> Data and enter your netid in the "Auto-login username" field

    3. Next click on Connection -> SSH -> X11  on the left side, and check "Enable X11 forwarding", this will allow graphics to forward to your screen

    4. Finally, go back to "Session" and enter a session name and hit "Save". This will store these properties so that you can use them again by selecting the session and clicking "Load".

  5. Finally, click open on the bottom right and click Yes when prompted by the PuTTY Security Alert

  6. Enter your password when prompted. You will not see your password appear on the screen, but it is being typed!

  7. When successfully connected, you will see a terminal display something that looks similar to

  8. Now you are all set! To test if X Forwarding is working correctly,enter in the command line: xeyes and you should see the following window pop up

  9. If you are having trouble, please contact askIT@albany.edu

Windows Subsystem for Linux

On windows 10, you can run Ubuntu natively. Follow the tutorial from Microsoft here: https://docs.microsoft.com/en-us/windows/wsl/install-win10

SSH to head.its.albany.edu

Just as you would on a regular linux terminal, you can SSH directly to head.its.albany.edu

 

macOS

XQuartz

X11 is a communication protocol for "forwarding" graphics from one machine to another. In order to display graphics or run programs interactively with the Terminal, XQuartz must be installed. To download and install XQuartz, please click here

Terminal

To SSH to any of our resources (e.g., head.its.albany.edu, headnode7.arcc.albany.edu, lmm.rit.albany.edu), you can use the terminal in Mac. Here, we will connect to head.its.albany.edu.

  1. Install XQuartz if you have not yet done so.

  2. Right click on XQuartz in the toolbar.  Select Applications → Terminal

  3. Enter into the terminal: ssh [netID]@head.its.albany.edu  

    1. NOTE: Use the -Y option, if you need X forwarding. The first two characters of the netID is in lowercase.

  4. Enter your password when prompted. You will not see your password appear on the screen, but it is being typed!

  5. Type y when prompted by the security alert (you may not see this alert)

  6. After you are successfully logged into the ssh session, you will need to enter the following command:  touch .Xauthority

    1. NOTES:

      1. you only need to do this if the file does not already exist. 

      2. there is a "." at the beginning of the filename ".Xauthority"

  7. Now you are all set! To test if X Forwarding is working correctly, enter in the command line: xeyes

    1. you should see a window with eyes pop up

  8. If you are having trouble, please contact askIT@albany.edu

SSH Config

Alternatively, the ssh config file can be updated with the set of statements below on Windows or Mac. This will allow you to use a shorter ssh command at the terminal as ssh netID@hostname

On Windows and Mac workstations, the ssh config file can be optionally updated with:

Host servername1 servername2... Port 22

On Windows, the ssh config file is located at C:\Users\<netID>\.ssh

On a Mac, the ssh config file is at ~/.ssh