[one-users] iSCSI recipe

[christopher barry]

Ok great, thanks Ruben.

-C

On Fri, 2012-08-10 at 23:37 +0200, Ruben S. Montero wrote:
> 
> > 1.- Setup a System Datastore. As you plan to use iSCSI you are save
>         > with the ssh system datastore [1]
>         
>         So, this is confusing me: <pg 40 of Setting up and Managing
>         your Clo...>
> 
> 
> Ups, my fault, you need shared to handle migrations properly.
>  
>         This seems to contradict your statement above.
>         
>         My 'assumptions' are these:
>         
>         * The system datastore needs to be shared. In order to have it
>         appear on
>         the hosts, I must manually export it on the frontend, mount it
>         via nfs
>         on the hosts. Symlinks are all that appear in the system
>         datastore, and
>         these point to block devices that have been attached to the
>         hosts.
> 
> 
> Right
>  
>         
>         * Each host needs to attach to all iSCSI targets that are
>         needed by
>         guests running on the host. It's not entirely clear to me if
>         ONE handles
>         all that or not (assuming it does).
> 
> 
> ONE handles this by login/logout in an iSCSI session as needed
> 
> 
>  
>         
>         * a guest attaches to the symlink in the shared system
>         datastore, but
>         this link actually ends up pointing to a *local* iSCSI
>         attached block
>         device, so it does not become a 'bottleneck' to any IO
>         traffic.
> 
> 
> Well,  depending on the performance of your iSCSI server and
> networking, number of VMs, traffic generated...
> 
> 
>  
>         
>         Does any of that make sense, or am I way off base?
> 
> 
> It makes sense, ;)
> 
> 
> Cheers
>  
> 
> 
> 
> -- 
> Ruben S. Montero, PhD
> Project co-Lead and Chief Architect
> OpenNebula - The Open Source Solution for Data Center Virtualization
> www.OpenNebula.org | rsmontero at opennebula.org | @OpenNebula