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

Daniel P. Berrange berrange at redhat.com
Wed Nov 26 10:16:05 UTC 2008

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.


[1] STONITH == Shoot The Other Node In The Head
|: Red Hat, Engineering, London   -o-   http://people.redhat.com/berrange/ :|
|: http://libvirt.org  -o-  http://virt-manager.org  -o-  http://ovirt.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505  -o-  F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|

More information about the ovirt-devel mailing list