Public Linux login and workgroupserver

Public Access Linux - PAL



PAL the workgroup server cluster for public DESY access.



PAL can be used for interactive work, like text processing or e-mail, software development or short test cycles. Resource intensive jobs and long running jobs should be avoided, as the machines are shared among different users.

Details


PAL is a computer cluster, the ssh-access is steered via a load balancer. One should not use the hostname of a machine behind the cluster alias to log in.


Currently, the following production cluster exist:


  • pal-sld6.desy.de : Cluster with ScientificLinux 6 (64 bit)
  • pal-el7.desy.de : Cluster with CentOS 7 (64 bit)
  • paul.desy.de: Cluster with Ubuntu 16.04 (64 bit)
  • pal.desy.de currently is an alias for pal-sld6.


Login


PAL can be reached directly from the internal DESY network via ssh. To access it from external clients a connection e.g. via bastion.desy.de should be opened.
ssh user@pal.desy.de


PAL is open to every DESY user. We rely on each user to not overuse the system. Longrunning jobs, or jobs with high memory usage, should use other infrastructures. One should also limit the number of processes running in parallel.
We currently do not enforce these requirements - no jobs are killed. However, we inform users when their resource usage is too high. Currently, this is when CPU time is above 24h, and a single process occupies more than half of the available RAM.

Availability of different PAL versions


PAL with ScientificLinux installation are available for the whole support period of the distribution. This means that several installations will coexist.
The Ubuntu PAUL cluster will only be available in the latest LTS (Long Term Support) version, the focus being the availability of current software version. This means that PAUL version will change every two years.

Help and support


UCO should be contacted to report any problems when using PAL, support with installed software, or requests for additional software.