Helix/Login

Access to bwForCluster Helix is limited to IP addresses from the BelWü network. All universities in Baden-Württemberg are connected to BelWü. If your are in your campus network (e.g. in your office or in a campus WiFi) you should be able to connect to bwForCluster Helix without restrictions. If you are outside the BelWü network (e.g. at home), a VPN connection to your campus network or a connection to an SSH jump host in your campus network must be established first.

The login nodes of the bwHPC clusters are the access point to the compute system, your $HOME directory and your workspaces. All users must log in through these nodes to submit jobs to the cluster.

Prerequisites for successful login:

You need to have

• completed the 3-step registration procedure.
• set a service password for bwForCluster Helix.

1 Prerequisites for Login

• You have set up a time-based one-time password (TOTP) for the two factor authentication (2FA) log in.
  • If this is still missing, then please follow the instructions for registering a new 2FA token.

• Your IP is within the IP range of your university. Either you are working on a computer on your campus or you are connected via a virtual private network (VPN) to your university.
  • If you have an external IP (i.e. home office) and you are not connected via VPN to your university, you can not connect to bwForCluster Helix. Please consult the documentation of your university how to connect to your university via VPN.

2 Login to bwForCluster Helix

After registration bwForCluster Helix can be accessed via Secure Shell (SSH). Only SSH is allowed for login.

From Linux machines, you can log in using the following command:

ssh <UserID>@helix.bwservices.uni-heidelberg.de

To run graphical applications, you need to enable X11 forwarding with the -X option:

ssh -X <UserID>@helix.bwservices.uni-heidelberg.de

For SSH client programs with graphical user interfaces, fill in UserID and login server name accordingly. For Windows you can use PuTTY or MobaXterm. The later comes with an integrated X11 server which is necessary for the work with graphical applications.

The bwForCluster Helix has serveral login nodes. The selection of the login node is done automatically. If you log in multiple times, different sessions might run on different login nodes. In general, you should use the generic hostname given above to allow us to balance the load over the login nodes.

3 Allowed activities on login nodes

The login nodes are the access point to the compute system and to your $HOME directory. The login nodes are shared with all the users of the cluster. Therefore, your activities on the login nodes are limited to primarily set up your batch jobs. Your activities may also be:

• compilation of your program code and
• short pre- and postprocessing of your batch jobs.

To guarantee usability for all the users of the bwForCluster you must not run your compute jobs on the login nodes. Compute jobs must be submitted as Batch Jobs. Any compute job running on the login nodes will be terminated without notice.