Proposal to use Debian Lenny as the standard Linux distribution at AEI

The AEI IT Linux policy is to have one "reference Linux platform" that IT will fully support and install per default on workstations and laptops, unless the user specifically asks for a different Linux distribution. In this case IT will provide support only on a "best effort" basis, but the user would mostly be responsible for his/her own support on that machine. This allows IT to focus on a single distribution, and to provide the highest level of support for that platform. It also allows IT to develop a standardized set of install packages that should cover ~99% of the typical Software packages physicists end up requesting.

This reference IT Linux platform is currently Ubuntu, which is a Debian derivative.

At the CCIT in February 2009 it was proposed to change our reference Linux distribution to Debian Lenny instead of Ubuntu.

The main arguments in favor of this switch are:

2 out of the 5 scientific groups at the AEI are heavily involved in LSC data analysis. Debian Lenny is one of the two "reference platforms" of the LSC (the other is CentOS5), and the AEI (Carsten, Henning, Steffen, Miroslav) is one of the main providers of Debian packages for the LSC Software Data-analysis and grid tools. For LSC members it would therefore be very beneficial to be able to use the LSC reference platform: it would allow to easily install LSCSoft and related software simply via Debian packages, and this software and grid-tools would work out-of-the-box.

Ubuntu is "similar" to Debian, but not identical: our LSCSoft package suite does not install without problems on Ubuntu (see Dierk's email), and our manpower for packaging is limited. Providing another suite of packages for Ubuntu would be a substantial extra burden on our cluster admins.

the three LSC clusters at the AEI (merlin, morgane, atlas) are (or will soon be) running Debian Lenny. IT and the cluster-admins (Steffen, Carsten, Henning) could therefore benefit from shared expertise, experience and tools, which in the long run should reduce the amount of work for support.

Lenny is a stable release, which will be supported for about 2-4 years, and will not move during that time, other than by bugfixes. However, updates are officially available via then 'lenny-backports' branch, and also additional inofficial channels. (In many cases, if necessary, packages can also be selectively upgraded by judiciously picking newer versions from the 'testing' branch in Debian).

Important questions to be considered:

• Q :will all hardware (laptops, ...) be sufficiently supported under Lenny? Would this be any harder than on Ubuntu?
  A : I have not heard IT voice any concerns in this respect

• Q : support for mobile devices?
  A : ?

• Q : support for LotusNotes
  A : Dierk does not think this should be an obstacle. deb packages exist, runs on various Lenny Laptops, eg Carsten, Reinhard.

• Q : are any scientific groups at the AEI tied to particular software that would rule out the use of Debian completely?
  A : not according to the replies collected in my survey, below

Note: before an actual transition, a standard set of packages and setup should be worked out in collaboration with the scientists, so that the first versions will already meet "typical" requirements without constant re-install of missing packages.

Discussion

On 12 Feb 2009 an email was circulated to the CCIT requesting input from all 5 science groups and IT on this proposal. There has been responses from Dierk Linsenmaier, Gerhard Heinzel's group, email2, Luciano's group: email1, email2, email3.

The main feedback seems to be: users generally seem happy with Ubuntu, and not very enthusiastic about a switch to Lenny, but have not voiced any strong objections either. IT (Dierk) estimated the manpower required to be ~40-50 man-hours, but doubts they are available with the current priorities of IT.

There seem to be no strong arguments that would rule out a transition, the decision would therefore be up to the CCIT. At the meeting 06 April 2009 it was decided to bring this forward to a vote.

-- ReinhardPrix - 29 May 2009