Re: ::scr Cesium

[David Cantrell <david@xxxxxxxxxxxxxxx>]

On Wed, Oct 31, 2001 at 02:53:23PM +0000, Piers Cawley wrote:
> David Cantrell <david@xxxxxxxxxxxxxxx> writes:
> > Riiiight. Without a multi processor box with some deep DEEP voodoo
> > that won't be possible. You'd need to stop a processor, bring up the
> > new kernel on that one, then stop all the others and bring up the
> > new kernel on them. But there will be a point where you are running
> > both kernels. And what of in-memory structures which change from one
> > kernel to the next? Even in the mainframe world you have to down the
> > machine to replace the most fundamental pieces of software.
> Actually, there are/were Vax/VMS clusters with uptimes into double
> digit years, that in their most recent incarnations were running an OS
> that was a couple of major revision numbers higher than where they
> started, and where none of the hardware in the cluster had been there
> when the cluster started.

Clusters, however, let you down individual boxes in the cluster whilst
still keeping the cluster running.  That is the whole point of a cluster
after all!  But you can't upgrade VMS on a single box without downing the
box at some point.

-- 
David Cantrell | david@xxxxxxxxxxxxxxx | http://www.cantrell.org.uk/david

             If a job's worth doing, it's worth dieing for