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

[Daniel P. Berrange]

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.

Daniel

[1] STONITH == Shoot The Other Node In The Head
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