Becoming a medusa user

Medusa accounts can be requested using the

      Ligo Scientific Collaboration Virtual Organization Computer Resource Request Form

Users are encouraged to connect to the Medusa cluster using Grid tools. These tools are included in the

      LSC DataGrid Client

package. You should install the package on your local workstation or laptop.

To use the tools in the LSC DataGrid Client package you will need a DOEGrids Personal Certificate for authentication. If you need to obtain a DOEGrids Personal Certificate, please navigate to LSC Data Grid web site

      Getting a Digital Certificate

for instructions. Grid-enabled versions of SSH, FTP and other tools are available to make life easier. Please see:

      Quick Introduction to LSC DataGrid Client Tools

for full instructions on how to obtain and install the software.

Medusa User Policies

Currently the Medusa cluster has 296 slave nodes and a number of master nodes, but you MUST log into hydra and not one of the other masters. We have a web page with documentation regarding accessing the cluster. Documentation for users is minimal, but under development, so suggestions are welcome:

http://www.lsc-group.phys.uwm.edu/beowulf/medusa/index.html

Your home directory is visible from all machines, so you should be able to pick up auxilliary files from there as you need to. If you have problems with the system, please submit a problem report by going to our web page and following the link at the top of the navigation bar; use guest/guest as the user/passwd and change the database toggle switch to medusa. We will deal with the issue as time permits. Please attempt to understand the classifications of bugs and use the appropriate urgency identification.

Also, a few rules about our system:

1. Please do not write output to your home directory, this may cause noticable performance issues. See #2.
2. Please do not keep large amounts of data in your home directory. We back up the home directories once a week and do not have the resources to deal with problems at this time. If you want to store data temporarily use the space in /scratch which is accessible from all nodes.
3. Please be aware that the computer you log into is used by several people. Please don't run major code on it. Use it for compiling and minimal testing.
4. If you have a very urgent problem, please e-mail medusa-admin@gravity.phys.uwm.edu about it.