Login

Login nodes

The cluster provides four login servers that allow you to connect to the cluster (e.g. for submitting and monitoring jobs or editing of files). The login servers can be reached using the hostnames

carl.hpc.uni-oldenburg.de
eddy.hpc.uni-oldenburg.de

Using either of the two hostnames will connect you to one of the login servers which have the hostnames

hpcl00[1-4].hpc.uni-oldenburg.de

and are assigned in an round-robin fashion (to distribute the load on the login servers). You can also use these hostname to login to a specific server but should only be used when needed.

Intranet

If you want to connect to the cluster from a windows computer, you can use your favorite ssh client (MobaXterm, PuTTY, OpenSSH, WinSCP) on Windows- and Linux-Computers or the command line (primarily on Linux-computers).

Connect to CARL/EDDY using MobaXterm

"MobaXterm" is the recommend way to connect to the cluster from a Windows computer. The following lines will describe the basic usage of the program.

The newest version of MobaXterm can always be found here: Download

After downloading and installing you are ready to use the program. Once you opened it, click on "Session" in the top left corner. Fill in the following informations:

If you want to connect to EDDY, simply replace "carl" with "eddy" (-> eddy.hpc.uni.oldenburg.de).

As always, replace "abcd1234" with your own username. There are many settings that can be modified, for this example we will not change them though. Confirm by clicking on "OK". A new tab will open and you will be prompted to enter your password.

After typing it in and confirming it with ENTER you are succesfully connected to the cluster.

You will probably immediatly see a big difference to other ssh clients: you can easily browse through the folders on the clusters without using the command line. The sidebar will look like this:

You can even drag&drop files on the cluster with this sidebar, which makes handling files very easy.

Connect to CARL/EDDY using PuTTY

We recommend to use "mobaXterm" since it offers more features and is more user-friendly. Nonetheless its your choise and if you want to use PuTTY you can follow these instructions:

Download the latest version of PuTTY from this link: Download

Enter the url "carl.hpc.uni-oldenburg.de" under the field "Host Name (or IP adress)":

Make sure the Port is set to "22" and the connection type is "SSH". Confirm by pressing the button "Open".

A new windows will popup and you have to type in your username (e.g. "abcd1234):

After you confirmed by pressing ENTER, you will be asked for your password. Type it in and confirm with ENTER again. You are now connected to the cluster.

If you want to connect to EDDY, simply replace "carl" with "eddy" (-> eddy.hpc.uni.oldenburg.de).

If you want to copy files from or on the cluster, you will have to use the program "WinSCP".

Connect to CARL/EDDY using the command line

Users of CARL can connect by typing:

ssh abcd1234@carl.hpc.uni-oldenburg.de

Similarly, users of EDDY login by typing:

ssh abcd1234@eddy.hpc.uni-oldenburg.de

If you want to use graphical applications on the login nodes (e.g. an editor like gedit) you need to enable X-forwarding:

ssh -X abcd1234@carl.hpc.uni-oldenburg.de

Internet

First, you have to establish a VPN tunnel to the University intranet. After that, you can login to CARL or EDDY via ssh as described above. See the following instructions on how to setup the VPN tunnel:

Windows

Download the Cisco-VPN-Client from this web site and install it following the instructions of the IT Services.

When you start a VPN tunnel by pressing connect, you will be prompted for your university user name and password.

Linux

First you may need to install some additional packages. This can be done e.g. with the command:

sudo apt-get install network-manager network-manager-gnome network-manager-vpnc vpnc

You will be prompted for the password on your local machine. If you are using KDE install network-manager-kde instead of the -gnome one.

To setup the VPN connection click on the network status (upper left of your desktop) and select VPN connection-->Configure VPN. Now you can either select Add or Import. After selecting "Add", enter the information manually as described in the instructions of the IT Services. If you want to import the settings, you will need to download the PCF-File. After selecting the option "Import", choose the previously downloaded file. You will now be forced to enter your account credentials.

If, after trying the above, you cannot setup you VPN using the Cisco VPN Client, you can try to install openconnect with

sudo apt-get install network-manager-openconnect-gnome

After that, proceed as before and select the Cisco AnyConnect Comaptible VPN. In this configuration, you only need to enter your username and password to conncet.

To connect click on the network status again and select the VPN connection you just configured.