Andreas, I would like to hear your ideas for how this process can be
improved. Let me explain what has happened so far.

Experiment readiness: At the June and July GDBs and more than one MB the
LHC VOs were asked if they were ready for SL4. They all replied that
they were. CMS wanted it right away and the others could use either SL3
or SL4 but wanted to stop verifying their software on SL3. We saw no
reason not to believe them. What are these major problems that the
others now see? Or are you talking about non-LHC experiments? If so then
it is up to a site to weigh the balance of pressure from experiments and
decide which opsys to support. At my site we will run SL3 and SL4 and
move the resources between the two in response to experiment
requirements (in one direction only). 

Site Readiness: after the July GDB a number of sites tried installing
the WN middleware on top of SL4. Experiments tested their code at these
sites and no-one reported any problems. This was reported at the weekly
operations meeting on 9 and 16 July. Again, no-one raised any
objections. 

LHC experiments will be running large scale tests this autumn. This will
not be a good time for widespread changes, hence the push for SL4 now.
How would you have ensured that things go smoothly? Test at every site?
Test for ever? Test at your site? It would be good if there were
absolutely certain comprehensive criteria against which to test
successive releases but these never appear. Realistically, the
experiments don't have the effort to write their main codes, never mind
keep tests up to date.

John Gordon   

> -----Original Message-----
> From: LHC Computer Grid - Rollout 
> [mailto:[log in to unmask]] On Behalf Of Andreas Haupt
> Sent: 31 July 2007 14:58
> To: [log in to unmask]
> Subject: Re: [LCG-ROLLOUT] RPMs in SL4 WNs
> 
> Hi,
> 
> so what's the status quo now? If I want to install new nodes: 
> which version shall I install? SL4 (32 or 64 bit) or SL3, 
> gLite 3.0 or 3.1?
> 
> There are some bad "issues" with the SL4 packages:
> 
>      1. Dependency on CASTOR-client: this is only part of SLC4. Are we
>         forced to install SLC? IMHO everything should install 
> fine with
>         pure SL coming from Fermi.
>      2. The need for external repositories like DAG and 
> JPackage: It is
>         IMHO really bad practise to blindly trust external 
> sources like
>         it is done now. You might want to do this on desktops - but on
>         servers? If you need external packages, put it into
>         RPMS.external.
> 
> To my mind the gLite-SL4 repos are not production ready by 
> now. So I'm really curious how the Management Board can 
> decide to push the deployment of SL4. They're actually right, 
> but leaving the sites alone and let them do fiddle around the 
> problems is not a solution.
> 
> The current situation is really unclear to me. Some 
> experiments like CMS are pushing the sites to install SL4. 
> Others still have major problems with it. It is now just good 
> luck to buy hardware that is able to run SL3. In some months 
> the same problem will arrive SL4 (new hardware support for 
> RHEL4 ends this year...). Did anyone ever tried to port gLite to SL5?
> 
> Cheers,
> Andreas
> 
> -- 
> | Andreas Haupt             | E-Mail: [log in to unmask]
> |  DESY Zeuthen             | WWW:    
> http://www-zeuthen.desy.de/~ahaupt
> |  Platanenallee 6          | Phone:  +49/33762/7-7359
> |  D-15738 Zeuthen          | Fax:    +49/33762/7-7216
>