Re: [libvirt] image locking?
On Wed, Oct 15, 2008 at 01:47:36PM -0700, Itamar Heim wrote:
The main issue is indeed across nodes. As you pointed out, fnctl()
won't
solve the issue for iSCSI.
What about the leased lock mechanism, for example, with libvirt playing
an external watchdog and terminating the qemu process if it cannot renew
the lock, or a central (nfs? Central service) storage to maintain the
global locks.
When you get to that level of cleverness, it seems to me that it is verging
on a complete re-implementation of DLM (distributed lock manager), which
really, AFAIK, needs a proper cluster setup so it can safely fence
mis-behaving nodes, and avoid quorum/split-brain problems.
Daniel
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