LXPLUS Service

This service (Public Login User Service) is the interactive logon service to Linux for all CERN users. The cluster LXPLUS consists of public machines provided by the IT Department for interactive work.

The machines in the LXPLUS service are a cluster of PCs running Linux. They run CC7 (CERN CentOS 7 http://linux.web.cern.ch/linux/centos7/) in 64 bit mode. They are arranged in a load balanced cluster and to access it, log on to the service: lxplus.cern.ch

A C8 (Centos 8) version of the service is also available. To access the C8 version, log on to the service: lxplus8.cern.ch

To login onto LXPLUS is by using SSH. SSH is also available on Windows machines (PUTTY). If you run an X Server on your local machine (X or Exceed), you can configure the SSH to tunnel X, to be able to run X applications (like xemacs, xterm ,etc...) on LXPLUS: To enable X-11 forwarding in PUTTY, select Connection->SSH->Tunnels on startup of PUTTY and check Enable X11 forwarding

You'll get connected to the machine that'll give you the best response, i.e. with the lowest CPU load and least number of login sessions. Please don't refer to particular machines when connecting to the LXPLUS cluster, because we do not guarantee that individual machines are available at any given time. If you want to run acron jobs on LXPLUS, please use 'lxplus' instead of particular machine names as well.

All interactive and batch systems are built on top of the CERN standard Unix Environment. This uses the HEPiX scripts to define the user environment, which comprises the variables necessary applications to correctly operate in CERNs environment of services and gateways and to find any necessary auxiliary tools. This is a multilayered environment, where the CERN defaults can be further customized by the Group or the individual.

A wide range of shells are made available, which fall broadly into two types, the C-shell like and the Bourne-shell like, and for each family there is a recommended choice; With the move to fully Linux based facilities the bash shell is now gaining popularity. It is possible to open X-sessions on these PLUS servers also.

LXPLUS machines can not be used to store long term data. They have large local directories for temporary storage (/tmp) but these are by necessity cleaned regularly, and therefore the data lifetime is not guaranteed at all there. Instead the machines all have access to the AFS file system for home directories, group space and some degree of scratch space, all of which are accessible through normal file system commands. In addition for physics and bulk data there is the EOS service which is accessible through put/get operations of the commands like xrdcp as well as fuse mountpoints.


The PLUS service (Public Login User Service) is the interactive logon service to Linux for all CERN users.
The cluster LXPLUS consists of public machines provided by the IT Department for interactive work.
All machines run AFS and offer access to the usual public services, like

  • AFS home directories
  • the CERN Mail Server
  • CERN Print System
  • the CERN batch system HTCondor
  • Network Services
    • WWW
    • ssh , scp
    • further services

The service is intended for interactive work, so please refrain from running CPU intense jobs on these machines. Jobs consuming lot's of CPU for extended periods of time will be killed automatically. If you have run CPU intense jobs, please use the CERN HTCondor batch system.