Open Stack

> So others have/will chime in here... one thing I think is kinda missing in
> the statement above is the "single host", that's actually the whole point
> of Ceph and other vendor driven clustered storage technologies out there.
> There's a ton to choose from at this point, open source as well as
> proprietary and a lot of them are really really good.  This is also very
> much what DRBD aims to solve for you.  You're not tying data access to a
> single host/node, that's kinda the whole point.
Current status of the DRBD driver is: you can have redundant (replicated) storage 
in Cinder, but the connection to Nova is still done via iSCSI.

> Granted in the case of DRBD we've still got a ways to go and something we
> haven't even scratched the surface on much is virtual/shared IP's for
> targets but we're getting there albeit slowly (there are folks who are
> doing this already but haven't contributed their work back upstream), so in
> that case yes we still have a shortcoming in that if the node that's acting
> as your target server goes down you're kinda hosed.
The WIP is that the Nova nodes use DRBD as a transport protocol to the 
storage nodes, too; that would implicitly be a multi-connection setup.

The Nova side
    https://review.openstack.org/#/c/149244/
got delayed to L, sadly, and so the Cinder side
    https://review.openstack.org/#/c/156212/
is on hold, too.

(We've got github repositories where I try to keep these branches 
up-to-date for people who want to test, BTW.)


Of course, if the hypervisor crashes, you'll have to restart the VMs (or 
create new ones).


If you've got any questions, please don't hesitate to ask me (or drbd-user, 
if you prefer that).



Regards,

Phil


-- 
: Ing. Philipp Marek
: LINBIT | Your Way to High Availability
: DRBD/HA support and consulting                 http://www.linbit.com :

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