The Noctua cluster[Bearbeiten]
Noctua is the first phase of the Noctua-project and will be extended 2020/2021 by the second phase.
Please note, that you can only log in to Noctua if you are a member of a project that has been granted computing time on the Noctua cluster by the resource allocation board. If you are not yet a member of an accepted project you can:
- ask the project administrator of an accepted project to add you as a user
- or submit a proposal for computing time. Please follow the instructions at .
How to access Noctua[Bearbeiten]
Noctua uses a "jump host" as a load balancer
From fe.noctua.pc2.uni-paderborn.de you can then establish an ssh-connection to one of the two physical frontends of Noctua.
For the authentication, you can
- use password-based or ssh-key-based authentication as a user from Paderborn University.
- We recommend ssh-key-based authentication with password-protected ssh-keys.
- As an external user, you can only use ssh-key-based authentication due to security considerations.
- If you have not yet deposited a key, please send us the public key of your SSH keyring to firstname.lastname@example.org. We can then install it for you.
Instruction on how to create an ssh-key can be found at . Only keys that are password-protected are allowed to be used in the context of PC² cluster systems.
We recommend the following combined command for an interactive session:
ssh -t fe.noctua.pc2.uni-paderborn.de ssh noctua
Alternatively, you can put
Host noctua HostName fe.noctua.pc2.uni-paderborn.de User [USERNAME] RequestTTY force IdentityFile [PATH TO PRIVATE KEY] IdentitiesOnly yes RemoteCommand ssh noctua
in your ~/.ssh/config and replace [USERNAME] with your username on Noctua and [PATH TO PRIVATE KEY] with the path to your private key of your ssh-key. Then you can use the short command ssh noctua to connect to Noctua. You will be asked for the password of your ssh-key when logging in instead of your user password.
If you want to connect to the last connected frontend, then use this command:
ssh -t fe.noctua.pc2.uni-paderborn.de ssh noctua-last
If you need to a run graphical application, the -X option should be used, which enables X11 forwarding with X11 SECURITY extension. The complete command is
ssh -X -t fe.noctua.pc2.uni-paderborn.de ssh -X noctua
Further information for accessing Noctua by using SSH public key authentication can be found here.
Access for Programs[Bearbeiten]
For programs like Visual Studio Code  that support remote development via ssh, you need a different ssh-config to deal with the load-balancer. You can add the following blocks to your ssh-config:
Host noctua-jumphost Hostname fe.noctua.pc2.uni-paderborn.de User [USERNAME] IdentityFile [PATH TO PRIVATE KEY] IdentitiesOnly yes Host noctua-ln1 Hostname ln-0001 User [USERNAME] ProxyJump noctua-jumphost IdentityFile [PATH TO PRIVATE KEY] IdentitiesOnly yes Host noctua-ln2 Hostname ln-0002 User [USERNAME] ProxyJump noctua-jumphost IdentityFile [PATH TO PRIVATE KEY] IdentitiesOnly yes
This will instruct ssh to use the host noctua-jumphost as a proxy when trying to connect to one of the frontends noctua-ln1 or noctua-ln2. We recommend to explicitly choose a frontend here because programs like Visual Studio Code run a daemon on the remote host and by explicitly choosing a frontend you avoid issues if you want to use multiple program instances. In programs like Visual Studio Code you can then simply select to ssh configuration noctua-ln1 or noctua-ln2 to connect to. Please don't use this way for interactive sessions.
First Steps on Noctua[Bearbeiten]
After you have successfully logged in to Noctua we recommend you to:
- Try out pc2status. This command-line tool gives you an overview of the projects you are a member of, the used computing times, monthly contingents, and file system quotas.
- Get familiar with Slurm which is the workload manager used on Noctua because you need it to do computations on the cluster.
- Have a look at the software already available on Noctua.