Operating Systems at DESY
The various FLC hosts run several operating systems:
- DESY Scientific Linux 4 (SLD4) is the DESY flavour of Scientific Linux 4, which is in turn a modified variant of Red Hat Enterprise Linux 4. SLD4 is currently the standard operating system in the DESY computing environment.
- DESY Scientific Linux 3 (SLD3) is the predecessor of SLD3 – the DESY flavour of Scientific Linux 3, based on Red Hat Enterprise Linux 3. SLD3 is still supported, but phasing out.
- DESY Scientific Linux 5 (SLD5) is the latest version of Scientific Linux. It is not yet officially distributed by the DESY IT, but the test phase has begun.
- DESY Linux 5 (DL5), based on SuSE Linux 8.2, is the predecessor of SLD3. Even though it can still be found on some FLC computers, it is outdated and computers running DL5 should be updated.
- DESY Linux 4 (DL4), based on SuSE Linux 7.2, is the oldest operating system which can be found on very few FLC computers. DL4 systems are not supported anymore by the DESY IT. For security resons, computers running DL4 must be updated as soon as possible.
For you as a user there should be only minor differences between the operating systems. However, you have to keep in mind that you should recompile your software if you’d like to run it under a different operating system because the systems use different compiler versions by default – if you forget this, you may get rather incomprehensible error messages or crashes. Furthermore, keep in mind that symbolic links which make use of the “@sys” mechanism in the AFS will take you to another destination (or may become invalid).