Dear Troy,

first of all: I won´t be at Taipeh to discuss in person. I´ll add a few 
concerns to this mail.

On Mon, 13 Oct 2008, Troy Dawson wrote:
> **Support time line for Scientific Linux 4
> Spring 2008 Hepix we decided that SL 4 would be supported until 2010 October 
> 10
> Do the labs still feel this is a good date?

My statement last time was: "Don´t make it shorter than the SL3 lifetime, 
otherwise people won´t migrate." - in fact, I consider this a general 
guideline because I don´t see that we can skip any SL release completetly, 
and the lifetime commtiment for a successor should always be larger than 
that of the current release.

Personally, I do not yet see a need to extend it for SL4. DESY is actively 
deploying SL5 in house and encouraging people to use it.
SL4 (32 bit) is used by the HERA collaborations, and they may have to 
maintain legacies beyond 2010. No clear signals yet. 
And SL4 is running on GRID systems. It would be helpful to hear about the 
LHC OS deployment strategy.


> Red Hat changed their support structure
> Here is Red Hat's support policy 
> https://www.redhat.com/security/updates/errata/

Interesting reading. I haven´t followed their policies closely in the 
past, but it seems that
a) support cycles are longer now
b) they take he liberty of "software enhancements" in the production
    phase, i.e. they make break useability or compatibility for
    applications with minor updates

One such case is firefox3 in 4.7 and 5.2. - we have several problems with 
it:
- FF3 comes without our root certificates (German Telekom and DFN), and 
for more than 12 months now the Mozilla foundation has not reacted to 
numerous requests of including them again. Users updating to FF3 basically 
have no access to some of our essential web services until they manually 
install our root certificates. 
- FF3 does not integrate well with our lprNG printing system
- FF3 is hammering AFS homes with profile and cache data

If anyone else shares these problems, I´d be interested in their solution 
approaches. For us it means that some groups will stay on 4.6 and 5.1 for 
prolonged times.

There´s a potential pitfall here for sites like DESY with a variety of 
user communities: We may end up supporting several minor releases in 
parallel over extended periods. Someting like the "move to 3.0.9 and 
freeze" which we did at the EOL of SL3 may not be feasible for SL4.


Side note: MacOS seems to be creeping faster than Ubuntu here. Both don´t 
come as Enterprise platforms yet, but are deployed on "personal" devices 
without centralized system support or deployment tools. 
It´s mostly an integration and user support problem so far.


To all SL developers & contributors:
Thank you for keeping us running!

With best regards,
Knut