Terminal Access

Users can gain command line access to HPC through our OOD web interface as an alternative to using a local SSH Client. To use this interface:

1. Log into https://ood.hpc.arizona.edu/
2. Go to the dropdown menu at the top of the screen and select Clusters
3. Click Shell
4. This will put you on the command line on one of the login nodes where you may perform regular housekeeping work, submit jobs, or request an interactive session.. By default, you will automatically be connected to Puma. To navigate to a different cluster, use the displayed shortcuts. 

Virtual Desktop

Users may also interact with a cluster using a virtual desktop interface. To do this:

1. Log into https://ood.hpc.arizona.edu/ and, under My Interactive Sessions, select Interactive Desktop under Desktops on the left-hand side of the page.
   
   
2. A form will appear where you will select the target cluster, enter the amount of time you'd like to be allotted (in hours), the number of cores you need, your PI Group (if you are unsure what your group name is, you can check in https://portal.hpc.arizona.edu/portal/), and the queue. Once you've filled in your request, click Launch.
   
3. A window will appear with the status of your request. It will start in a Pending state and will switch to Running when your desktop session is ready. Click Launch Interactive Desktop to access your session.
   
4. That's it! You can now use the cluster with a Desktop interface
   

• All the integration on UArizona HPC supercomputers is done with the  "bash” shell which means to get consistent results, bash must be your shell.  New HPC users automatically are set to the bash shell unless they already are using a different shell.

• When using SSH, if you leave out the netid@ then it may default to your workstation username, which may not be valid; on Linux and MacOS you can override this via a ~/.ssh/config "User netid" config line. On Windows, there may be an application-specific way to set the username for hpc.arizona.edu connections.

• If you try to log in and get a continuous prompt of "password" and nothing else, you are probably not registered for NetID+. 

Mac Access

Mac systems provide a built-in SSH client, so there is no need to install any additional software. You will find the terminal application under Applications → Utilities → Terminal.

Open the terminal and enter:

$ ssh netid@hpc.arizona.edu

where netid is your UArizona NetID. When you press enter, you will be prompted for your university password. Note: you will not see any characters appear on the screen while typing during this step. This is normal and everything is working as it should. After successfully entering your password, you will be prompted to Duo Authenticate. If everything is successful, you will be connected to the bastion host.

Windows Access

Windows systems do not have any built-in support for using SSH, so you will have to download a software package to do so. There are several available for Windows workstations.  Free SSH clients are available for download from the University of Arizona's Site License website.  

PuTTY

PuTTY is the most popular open source SSH Windows client. To use it: download, install, and open the Putty client. Next, open a connection and enter hpc.arizona.edu under Host Name and press Open

This will open a terminal. At the prompt, enter the following, replacing <netid> with your own NetID:

Login as: <netid>

You will then be prompted to Duo-Authenticate. If the process is successful, you will be connected to the bastion host.

MobaXterm

MobaXterm is another available SSH Windows client. To connect to HPC, download and install MobaXterm, open the software, select Session → SSH and enter hpc.arizona.edu under Remote host. Next, select the box next to Specify username and enter your UArizona NetID. To connect, click OK at the bottom of the screen:

This will open a terminal and will prompt you for your UArizona password. You will then need to Duo-authenticate. If everything is successful, you will be connected to the bastion host.

Linux

Linux systems provide a built-in SSH client, so there is no need to install additional software. Simply locate and run the Terminal app.

Open the terminal and enter:

$ ssh netid@hpc.arizona.edu

where netid is your UArizona NetID. When you press enter, you will be prompted for your university password. Note: you will not see any characters appear on the screen while typing during this step. This is normal and everything is working as it should. After successfully entering your password, you will be prompted to Duo Authenticate. If everything is successful, you will be connected to the bastion host.

Success. Logging you in...
Last login:
This is a bastion host used to access the rest of the RT/HPC environment.
  
Type "shell" to access the job submission hosts for all environments
-----------------------------------------

***
The default cluster for job submission is Puma
***
Shortcut commands change the target cluster
-----------------------------------------
Puma:
$ puma
(puma) $
Ocelote:
$ ocelote
(ocelote) $
ElGato:
$ elgato
(elgato) $
-----------------------------------------

$ echo $DISPLAY

X11 Forwarding on Mac and Linux

Start a terminal session and connect as you typically would with an additional flag -X in your ssh command (shown in the example below). Once you're connected to the bastion host, enter the name of the cluster you want to access, including the additional -X flag again. An example of this process is provided below:

$ ssh -X netid@hpc.arizona.edu
Password:
Duo two-factor login for netid
Enter a passcode or select one of the following options:

 1. Duo Push to XXX-XXX-8969
 2. Phone call to XXX-XXX-8969
 3. Phone call to XXX-XXX-0502
 4. SMS passcodes to XXX-XXX-8969

Passcode or option (1-4): 1
Success. Logging you in...
Last login:
This is a bastion host used to access the rest of the RT/HPC environment.
 
Type "shell" to access the job submission hosts for all environments
-----------------------------------------            
[netid@gatekeeper ~]$ echo $DISPLAY
localhost:13.0

[netid@gatekeeper ~]$ shell -X
***
The default cluster for job submission is Puma
***
Shortcut commands change the target cluster
-----------------------------------------
Ocelote:
$ ocelote
(ocelote) $
Puma:
$ puma
(puma) $

(puma)[netid@junonia ~]$ echo $DISPLAY
localhost:18.0

X11 Forwarding on Windows

To use X11 forwarding on a Windows system, you will need to download an X11 display server such as Xming. 

PuTTY

To enable X11 forwarding in PuTTY, go to SSH → X11 and select the box next to Enable X11 forwarding.

Once you've connected to the bastion host, connect to the login nodes with the an additional flag -X:

$ shell -X

MobaXterm

To enable X11 forwarding in MobaXterm, open a new session, select SSH, and open Advanced SSH settings. Select the option below called X11-Forwarding.

Once you've connected to the bastion host, connect to the login nodes with the an additional flag -X:

$ shell -X

SSH keys on Mac or Linux

In a Terminal session on your local workstation:

1. Create a public-key pair: 

   Code Block
   language bash theme Midnight
   $ ssh-keygen -t rsa

   You will be prompted to enter a passphrase. This is optional, but we strongly recommend that you do so.
   

2. After running that command, you will have two new files on your local computer: ~/.ssh/id_rsa and ~/.ssh/id_rsa.pub

   • id_rsa is your private key file. Do not share this with anybody! It is analagous to your password; anybody who has this file can impersonate you.
   • id_rsa.pub is your public key file. You will upload this onto any servers that you wish to automatically login to.
     
     

3. Copy the public key to the Bastion Host (you will need to enter your password this one time): 

   Code Block
   language bash theme Midnight
   $ ssh-copy-id netid@hpc.arizona.edu

   
   

4. If your computer does not support the ssh-copy-id command, run the following commands:
   

   Code Block
   language bash theme Midnight
   $ scp ~/.ssh/id_rsa.pub netid@hpc.arizona.edu: $ ssh netid@hpc.arizona.edu # (you will need to use your password this time) $ mkdir -p ~/.ssh && cat ~/id_rsa.pub >> .ssh/authorized_keys && rm ~/id_rsa.pub # On the server, copies the key into the appropriate file

   
   

Now, logout and attempt to login to the server again. You should not be prompted for a password!

SSH Keys on Windows

To setup SSH keys on Windows with the PuTTy client, refer to the official PuTTy documentation.