Accessing the Hoffman2 Cluster

You can connect to the Hoffman2 cluster using the SSH protocol. For command line-type operations, that do not require opening of graphical interfaces, using SSH will suffice. To allow on your local computer opening of graphical interfaces (GUI applications) running on the cluster you will need to allow forwarding of the X Window System over SSH. NX is an alternative way to connect to the cluster that allows opening of a remote desktop on the cluster (with access to graphical interfaces). You can also connect to the Hoffman2 cluster via ipython notebooks.

The first time you connect, your ssh client will show you a fingerprint and ask if you want to accept the connection. The fingerprint should match one of the following strings, or you should refuse the connection.



RSA key:


RSA1 key:


DSA key:


Starting with version 6.8 of OpenSSH the fingerprint is, by default, displayed as base64 SHA256.

Using SSH

Linux and Mac

UNIX-based system, such as Linux and Mac OS X, generally are equipped with an ssh client. Use the ssh command from a terminal:


where login_id is replaced by your cluster user name.


Install one of the following free ssh client programs:

  • PuTTY, How to Configure PuTTY.
  • MobaXterm SSH client including X11 server (for running GUI applications).
  • Cygwin a collection of tools which provide Linux functionalities in Windows systems.

Opening GUI Applications

You can run interactive applications that have Graphical User interfaces (GUI) by connecting to the cluster login node using ssh with X11 Forwarding enabled. Your local machine must be running an X server and enable X11 forwarding in order to display graphical output. See: Setting up X11 Forwarding for GUI Applications.

Remote Rendering on Hoffman2’s GPU nodes

It is possible to harness the computational power of Hoffman2’s GPU nodes to render images while displaying them locally. See: Setting up Remote Rendering on Hoffman2’s GPU nodes

Connecting via the NX protocol

NX is a free, secure, compressed protocol for remote X Window System connections for Windows, Linux, Mac OSX, and Solaris. We currently support connecting to the Hoffman2 cluster via the NoMachine client as well as the X2Go client.

NoMachine client

How to download, install, configure and run the nomachine nx client

X2Go client

How to download, install, configure and run the x2go client

Connecting via a Jupyter notebook

Please check: Connecting to the Hoffman2 cluster via a Jupyter notebook viewer.

Additional Topics

You may also access Hoffman2 Cluster account through UCLA Grid Portal web-based interface. Use your grid username and grid password. But this service will be taken down in near future. See this FAQ item.

Last edited, November 2017
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