[Infrastructures] ISconf version management proposal

[Steve Traugott]

Hi All,

See http://trac.t7a.org/isconf/wiki/VersionManagement -- I've written
up a description of how upgrades between protocol versions work in
isconf 4.  At the bottom I've included some proposals for how the
process might work in the future.  I'm leaning in favor of proposal
'A' right now, but I'd be interested in hearing what people think.

Overall, this is an interesting barrier-type problem, where we need to
manage state of an entire infrastructure as a whole, and not advance
to the next state until all machines are "at the barrier".  In this
case, the barrier is e.g. a 4.2->4.3 isconf upgrade -- we need to
preserve a means of serving backlevel machines until we're sure that
there are no backlevel machines left...

Feel free to edit the wiki page if anything jumps out at you.

Steve
-- 
Stephen G. Traugott  (KG6HDQ)
UNIX/Linux Infrastructure Architect, TerraLuna LLC
stevegt@TerraLuna.Org 
http://www.stevegt.com -- http://Infrastructures.Org