[Users] general (totally noob) questions...

[Michael Hauber]

On Sunday, September 23, 2012 03:13:56 PM Itamar Heim wrote:
> On 09/22/2012 08:00 AM, Michael Hauber wrote:
>>
<<snip>>
> > 
> > 
> > Questions:
> > 
> > 1.  As I understand it, a N-to-N configuration means that there will be
> > load balancing between the nodes as well as failover.  Is the load
> > balancing something that is manual (I have to monitor/balance the load
> > manually, or is it done automatically?)
> 
> ovirt has load balancing based on cpu load for either power saving or
> even distribution.
> more types and custom scheduling are coming.
> 
> > 2.  If it is done automatically, how do the loads get split up?  Is the
> > virtual machine itself the unit of load that transfers from one node to
> > another or does it go so far as balancing services running inside those
> > virtual machines?
> 
> VM is the unit of load.
> 
> > 3.  For the fail-over, is it seemless in the sense that the user's
> > connections don't get reset or is there a short period of down-time
> > before the service is available again?  While this isn't a big issue for
> > me, it is something that I've been wondering about.
> 
> live migration is seamless.
> failover is not, since the VM/host failed. engine needs to detect it,
> give some grace time, then start the VM on another host.
> 
> > 4.  Fibre channel or FCOE?  (I've spent entire evenings trying to get a
> > straight answer through google searches, but there seem to be way too many
> > agendas).  Being that one of the virtual servers will be a media server
> > for
> > the televisions (new addition), my worry is lag-time (I would like to
> > serve at least 5 televisions without lag-time).  The array will also
> > support things like file server, space for about 2-dozen www (family
> > pages (lots of pictures)), space for mail, space for backups
> > (rSync,Amanda), ISO boots, etc.
> I am obviously out of my element here for what i use for my family :)
> why FC and not Ethernet?
> 

First, thank you for helping me understand this a bit better.

Why FC...  I don't know?  I don't know how to figure out what kind of load it 
will see, so I figured that I would try for the fastest option I could afford.  
But like I said, some people swear by iSCSI, others by FC, and others by FCOE.  
Being that I've never gotten a chance to experiment with any of them (so far, 
I've just used a NFS/SMB server).

I don't know if it helps to explain or not, but the following two links show 
the network I would like to set up.  The first is the physical configuration.
The second shows the virtual machines that the cluster will run.

https://mikesplace.valleygate.net/temp/VIIgate_New_Physical.png
https://mikesplace.valleygate.net/temp/VIIgate_New_Node_VMs.png

Being that it's all going to be fiber and if NAS is enough, can I also assume 
that it's safe to consolidate the storage and the "cluster" switch and 
seperate them into two vlans without any kind of performance hit (don't know 
how busy the back-channel network would be).

Thanks again for the help.

mchauber