[sheepdog-users] 0.4.0 this weekend :-)

[Liu Yuan]

On 07/06/2012 12:37 AM, Alexandre DERUMIER wrote:
>>> all sheeps of one node in the same zone? should be for saftey or? 
> I'm not a sheepdog expert, but i think 1 zone by node is the right way ?
> 

Either is okay for sheepdog, gateway-only node don't count as storage
node. Storage node (non-gateway-only node) matters because we need
number of storage nodes >= copies to get cluster running (in case we
don't set nohalt flat when formatting).

There is something more to notice that non-gateway-only nodes can switch
to gateway-only node automatically when EIO (for e.g. disk error)
happens on local disks.

So basically gateway-only mode mostly targets for the case that you just
want to run sheep daemon as a request forwarder to the cluster (don't
store any data locally). But yes, you can even run VM through QEMU
without sheep daemon on local node!

Also we have to keep in mind that we can make advantage of object cache
(be it write-through mode or write-back mode) optionally to boost
performance even for gateway-only node.

Thanks,
Yuan