Interactive servers usage best practicesΒΆ

CC-IN2P3 provides interactive servers to prepare tasks before they are submitted to he computing platform: development, test, etc. Interactive servers are accessible with the following syntax:

% ssh -Y
  • is an alias that redirects to the least loaded server.
  • For Microsoft Windows users we recommend the use of PuTTY as an SSH client.

As each interactive server is shared by multiple users, we recommend a number of good practices to follow so that your activities can coexist with the other users activities.


Non compliance with these rules may result in some of your processes termination.

  • Only one computing process is allowed per interactive server and 3 processes over the entire interactive platform.
  • 24 hours CPU time maximum for a process and 1 hour CPU time for a multi-core process.
  • Parallel processes with intensive use of both CPU and input/output are not allowed (example: make -j, scons, b2, ninja, etc.) However, it is possible to run such processes as interactive jobs (see interactive jobs).
  • Avoid excessive memory consumption that could have an impact on the system. The command htop -u username may be a useful monitoring tool.
  • It is forbidden to run tasks in “batch” mode (eg: processing a large amount of files in loop).
  • /scratch is not a permanent storage space: data can be deleted at any time to free up space. Under normal circumstances data is deleted after 14 days. Also, avoid large data storage.
  • Detached and persistent processes after logout are not allowed (excepted when using Screen).
  • Please note that screen is neither meant as a substitute to the batch system, or as a way to run services nor as a way to hog scarse resources (like GPU interactive computing nodes).
  • Processes inactive for more than 24 hours are killed.
  • One transfer process is allowed per server (example: scp, rsync or dq2-get) and 3 processes across all interactive servers.
  • To preserve user data confidentiality, rmate (or other similar editor) requires using a random TCP port instead of a fixed port.