FAQ
The most frequently asked questions are listed below.
How do I get a user account?
DKRZ:
For access to the Mistral cluster system you need to be a member in at least one active HLRE project, have a valid user account, and accept DKRZ's "Guidelines for the use of information-processing systems of the Deutsches Klimarechenzentrum GmbH (DKRZ)".
More details are available on the DKRZ website.
RRZ:
For access to the Hummel cluster system your are welcome to use the HHCC contact form to request a user account. You may also contact hpc@uni-hamburg.de(//hpc"AT"uni-hamburg.de) directly.
RRZ members can also use RZ Bombus cluster at TUHH RZ and vice versa the Hummel cluster is also available for members of the TUHH.
More details are available on the RRZ website.
TUHH RZ:
For access to the Bombus cluster system you need to be a member of the TUHH and you have to fill in a user request form (PDF) checking the "HPC" box.
TUHH members can also use the Hummel cluster at RZZ and vice versa the Bombus cluster is also available for members of the RRZ.
More details are available on the TUHH RZ website.
How can I login?
All:
The three High Performance Computing systems at DKRZ, RRZ, and TUHH RZ can be accessed via Secure Shell (SSH) network protocol only.
DKRZ:
You can login to Mistral with the following ssh command, replacing <userid> by your username:
ssh -X <userid>@mistral.dkrz.de
More details are available on the DKRZ website.
RRZ:
Instead of using a password the Hummel cluster login is based on public-private key pair encryption for the ssh authentication.
For that purpose you have to generate a public-private key pair once.
An RSA key pair with a length of 4096 bits is on your local computer for example generated via
$ ssh-keygen -t rsa -b 4096 -f $HOME/.ssh/id_rsa_hummel
After generating the key pair you have to send the public key to hpc"AT"rrz.uni-hamburg.de so it gets installed on so-called gateway nodes.
Login to Gateway
First you have to login to one of two special Hummel gateways with the following ssh command:
ssh hummel1.rrz.uni-hamburg.de
or
ssh hummel2.rrz.uni-hamburg.de
Login to Frontend from Gateway
In a second step you login to one of two Hummel frontend nodes via ssh:
ssh front1
or
ssh front2
More details are available on the RRZ website.
TUHH RZ:
You can login to Bombus with the following ssh command, replacing <userid> by your username:
$ ssh -X <userid>@bombus.rz.tu-harburg.de
More details are available on the TUHH RZ website.
What are the names of the clusters?
DKRZ:
The Mistral cluster system was named after a strong wind that blows from southern France. It replaced DKRZ's IBM Power6 cluster named Blizzard in 2005.
More details are available on the DKRZ website.
RRZ:
The Hummel cluster system is named after Johann Wilhelm Bentz (1787-1854), a water carrier and "Hamburger Original" nicknamed Hummel. Hummel (bumble bee) is incidentally also the name of a social insect. Bumble bees form colonies with a single queen and many workers.
TUHH RZ:
The system is named Bombus cluster. Bombus is interestingly the scientific name for bumble bee (Hummel in German, also see RRZ above).
Which cluster hardware is available?
All:
A short description of the cluster hardware is given on our scientific equipment page.
DKRZ:
More details about the hardware are available on the DKRZ website.
RRZ:
More details about the hardware are available on the RRZ website.
TUHH RZ:
More details about the hardware are available on the TUHH RZ website.
What kind of operating systems are used on the clusters?
All:
The three High Performance Computing systems at DKRZ, RRZ, and TUHH RZ are based on 64-bit linux distributions.
DKRZ:
Red Hat Enterprise Linux (RHEL) release 6.4 (Santiago) is installed on the nodes of the Mistral cluster.
In 2017/2018 DKRZ will migrate to RHEL 7.
More details are available on the DKRZ website.
RRZ:
CentOS 7 is installed on the nodes of the Hummel cluster.
More details are available on the RRZ website.
TUHH RZ:
RedHat Enterprise Linux (RHEL) / CentOS 7 is installed on the nodes of the Bombus cluster.
More details are available on the TUHH RZ website.
Which batch system is used on the clusters?
All:
SLURM is used as workload manager and job scheduler at DKRZ, RRZ, and TUHH RZ.
DKRZ:
More details are available on the DKRZ website.
RRZ:
More details are available on the RRZ website.
TUHH RZ:
More details are available on the TUHH RZ website.
Which software is available on the clusters?
All:
Frequently used software is usually already installed on the HPC cluster system at DKRZ, RRZ, and TUHH RZ. For example: GNU Compiler Collection (gcc), Intel C++ and Fortran compilers, mvapich2 and Open MPI libraries, MATLAB, ParaView, Python, R, etc. Most of the installed software is normally available via so-called environment modules. Loading a module dynamically adapts your Linux environment to give you access to a specific application (e.g. compiler and MPI environment).
If required, other open source software or application packages can usually be installed in coordination with the local compute centers.
DKRZ:
More details are available on the DKRZ website.
RRZ:
One major focus lies on application software for the field of chemistry, e.g. ABINIT, ADF, Amber, Desmond, Gaussian, Gromacs, Molcas, Molpro, Turbomole, Quantum ESPRESSO.
More details are available on the RRZ website.
TUHH RZ:
The major focus lies on application software for engineering disciplines, e.g. Abaqus, Ansys, Comsol, Star-CCM+, MSC Nastran / Patran, MSC Marc/Mentat, OpenFOAM.
More details are available on the TUHH RZ website.