[Ovirt-devel] [PATCH server] Replace host-status with db-omatic.

[Ian Main]

On Wed, 26 Nov 2008 10:16:05 +0000
"Daniel P. Berrange" <berrange at redhat.com> wrote:

> On Tue, Nov 25, 2008 at 11:05:18AM -0800, Ian Main wrote:
> > This patch replaces host-status with db-omatic (formerly qpid-db-sync).
> > This uses the qpid console to recieve events from libvirt-qpid on various
> > nodes and update state in the database directly.  It also uses heartbeating
> > from the libvirt-qpid agents so it knows when a host or agent dies.
> 
> Correction - it knows when the libvirt-qpid daemon is non-responsive, 
> which is not the same as the host being dead - it is merely 'possibly'
> or 'probably' dead. It could be a failure of the network, or of the 
> daemon, or gremlins in the tubes. As long as we're not relying on this
> detection of death as a guarentee we're fine - to turn the 'probably'
> into a guarentee we ned to using cluster fencing to STONITH[1] upon
> libvirt-qpid detecting probable death.

Right, yes.  Good clarification.

	Ian