[Users] host raiding two LUN from different external storage

[Johan Kragsterman]

Hi!

Dan, it seems you know something about storage, so I adress you:

I find the oVirt storage framework a bit odd. It has it advantages, but also a lot of disadvantiages, it seems.

I did earlier, in this thread, ask about storage setups you want to use in enterprise environments. And I like to continue that discussion. 

If you like to replicate on SAN level between, let's say two different LUN's, that should contain the same informnation for a host, or for a VM, then you end up in trouble if you use the oVirt storage system. Because you need to put the two LUN's from the different datacenters together, to become ONE unit, otherwise you don't get the right uuid for live migration. Isn't right?

As you wrote earlier, this might be solved with gluster, but is it so, that oVirt is going to get enterprise features only in pair with gluster? I don't believe that is a good idea for the adoption of oVirt.

oVirt must have a good support for enterprise features that is used today, like NPIV. I have googled around oVirt and NPIV and didn't come up with much, you can tell me something about it?

I belive it would be good if oVirt supported other storage system types than the one system it supports today, that all storage should be imported and handled by LVM and oVirt engine.

Most enterprise storage today is fibre channel and NPIV based. You boot most the VM's through NPIV LUN's, you add more space through thin provisioning or more NPIV LUN's.
And this is going to continue, even if the Fc world move to FCoE.

So perhaps you can tell me a little bit about the storage strategy that oVirt dev team has?

Rgrds Johan


-----Dan Yasny <dyasny at redhat.com> skrev: -----
Till: Johan Kragsterman <johan.kragsterman at capvert.se>
Från: Dan Yasny <dyasny at redhat.com>
Datum: 2012.07.29 12:55
Kopia: users at ovirt.org
Ärende: Re: [Users] host raiding two LUN from different external storage

You can use replicated at the SAN level storage between different DCs, for DR. You can also use Gluster for the same purpose. 

Setting RAID1 between two geographically separate hosts is asking for trouble.


----- Original Message -----
> From: "Johan Kragsterman" <johan.kragsterman at capvert.se>
> To: users at ovirt.org
> Sent: Sunday, 29 July, 2012 12:08:20 PM
> Subject: [Users] host raiding two LUN from different external storage
> 
> Hi!
> 
> In some setups, like when you got two datacenters that works like
> failover sites, you would like to have two external raid
> controllers(storage devices), one in each datacenter.
> 
> You then send two identical LUN's, from each controller, to a
> cluster, let's say two hosts, for simplicity. What you normally do
> is to host raid these LUN's in mirror(raid 1), so the hosts write
> the same to both LUN's, and both controllers.
> 
> Question for me here is if I can accomplish this in oVirt management?
> Because if I can't, it will be a problem, because if I host raid at
> the host level, then the storage would be local storage for oVirt,
> wouldn't it? And then I suppose it can't be used for live migration,
> can it?
> 
>  Regrds Johan
> _______________________________________________
> Users mailing list
> Users at ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
> 

-- 



Regards, 

Dan Yasny 
Red Hat Israel 
+972 9769 2280