Stanford National Accelerator Laboratory
Computing Division

Linux at SLAC

SLAC Computing
LINUX-L Archives
Updated: 28 Mar 2013

Supported Linux Distributions

Red Hat Enterprise Linux

SLAC's recommended Linux for all machines is Red Hat Enterprise Linux (RHEL). Currently, two versions of RHEL are supported, RHEL6 and RHEL5.

RHEL is available for both 32-bit (IA-32) and 64-bit (x86-64) architectures. RHEL6 or RHEL5 are the recommended versions for new installs. Note that software built under RHEL6 will not run on a RHEL5 system; likewise, software built on a RHEL6/64-bit system won't run on a RHEL6/32-bit machine.

RHEL4 and earlier versions of RHEL are not permitted at SLAC.

SLAC has negotiated a site subscription to RHEL and has also purchased a support contract from Red Hat, which has proven quite valuable. In addition to helping us resolve a number of problems it has also given us early access to new releases and a voice in Red Hat's future directions.

Scientific Linux

Other Linux Distributions

The following are explicitly not supported:

  • RHEL4, RHEL3, RHEL2.1
  • SL6, SL5, SL4, SL3
  • Red Hat 9 or older
  • Fedora Core (any version)
  • Other Linux distributions (SUSE, Debian, etc.)

OS Updates

OS Release minimum
update level
RHEL 5 2.6.18-348.3.1.el5 2.5-107 RHEL 5.9
RHEL 6 2.6.32-358.2.1.el6 2.12-1.107.el6 RHEL 6.4

All earlier versions of the kernel or glibc are explicitly prohibited.

Preparing to install Linux

Installation and Maintenance Procedures for Linux at SLAC

Once you have installed Linux on your system, we strongly recommend that you also install taylor, the OCIO tool for maintaining UNIX and Linux systems. Instructions for installing taylor are included with the OS installation instructions in the Web pages referenced above. Among other things, taylor will automate the process of regularly applying operating system updates.

Please note that if you cannot run taylor (e.g., because you are using some other Linux distribution), or do not choose to run it, you are still responsible for maintaining your system. This includes but is not limited to such things as:

  • regularly installing security patches
  • removing or disabling local accounts when users leave SLAC
  • guarding the root password
  • complying with DOE security regulations (e.g., displaying the security banner during login)
  • reporting suspicious activities to OCIO, etc.
For more information about the requirements for maintaining a non-taylored Linux system, please send mail to

Other Information

Most of the following information is old and much of it is probably no longer relevant; use it at your own risk.

Public Linux Machines at SLAC

SLAC provides several categories of public Linux machines.
  • A Linux batch farm with over a 1000 nodes (most dual processors) running the LSF batch management software.
  • Several load-balanced pools of machines for interactive, compute-intensive work. These machines have generic names reflecting the particular operating system on the machines in the pool, e.g., "rhel5-32" for a pool of machines running the 32-bit version of RHEL5.
  • A smaller load-balanced pool, generic name "iris", for light interactive work, e.g., reading email, editing, Web browsing.
For more complete information about these resources, please see the Public Machines at SLAC WEB page.