Dialog server

Because practically all HPC-systems at RRZE use private IP-addresses that can only be reached from within the FAU, the dialog servers are the entry point for customers that want to access the clusters from the outside. Another alternative can be VPN, but that usually is more hassle.

Login to the dialog-servers is via SSH.

Available servers

• cshpc.rrze.fau.de – cshpc is a Linux-System that permits login to all HPC-accounts. A more verbose description of this system can be found below.

cshpc

Various software-packages like e.g. webbrowsers, mail clients, PDF readers or gnuplot are available on cshpc.

The standard filesystems (/home/hpc, /home/vault, $WORK, essentially everything that starts with /home/...) are directly reachable from this system as well, so that you can easily copy data around using scp.

Nomachine NX on cshpc

cshpc can also be used as server for Nomachine NX. NX enables use of a graphical desktop environment and applications (e.g. firefox) even over relatively slow connections (e.g. Hotel-Wifi abroad). In addition, it is possible to “park” sessions and resume them from elsewhere later, so in a way it is sort of screen for X. Your detached session keeps on running on the server, and when you reattach it later, all the applications you had open still are open. To use this, you will need the Nomachine Enterprise Client, available for Windows, Linux and MacOS. It can be downloaded for free from the Nomachine website.

The most important settings you will need to make when you create a new connection with the client are: protocol SSH, host cshpc.rrze.fau.de, port 22, Use the system login, Authentication by Password. Alternatively you can open this configuration file in your nomachine-client.

If you have an HPC portal account (i.e., if you do not have a password), you can configure the NoMachine client to use you private SSH key for authentication: Go to “Edit connection -> Configuration,” and select “Use key-based authentication with a key you provide.” Clicking on “Modify” lets you select a private key file.

While it is in principle possible to use Gnome or KDE4/Plasma desktops on cshpc, we do not recommend that. The reason is that these desktops nowadays require hardware 3D acceleration to be bearable, and the remote session cannot offer that, so using them will feel like molasses. In addition, in our experience Plasma crashes randomly at every second click if no 3D acceleration is available. We therefore recommend you use more lightweight desktop-environments like XFCE, or Trinity (KDE3). For the latter, you’ll need to click on “create a new custom session” in the client, and use the following settings:

• Run the following command: starttde
• Run the command in a virtual desktop

Because this system is shared by many users, it should be self-explanatory that you will need to be considerate of other users. Do not attempt to run things sucking up gigabytes of memory or long running calculations there.