On 01/29/2011 09:32 PM, Les Mikesell wrote:
> On 1/29/11 5:05 AM, carlopmart wrote:
>>>
>>> |> It is very important that the virtual machine consumes the least
>>> |> resources
>>> |> possible (host has 5GB RAM and i need to run three virtual machines
>>> |> minimum,
>>> |> including this storage server as a virtual machine).
>>> |
>>> | What's the point of adding an extra virtual layer compared to an nfs
>>> | or
>>> | iscsi share from the host (nfs if it is shared, iscsi if it is the VM
>>> | image store)? This seems like it would be more efficient if you run
>>> | exsi on the hardware with centos and the others as guests anyway.
>>> |
>>>
>>> There are some advantages that I can see in that if your hardware dies you can migrate the entire host and disks over to another VMWare hosts.
>>>
>>> If your NFS host is not H/A a loss of the host would take down the virtual machines too. Additionally, virtualization offers the ability to migrate the VM and disk to newer hardware somewhat transparently allowing you to take advantage of the latest/greatest/buggy tech.
>>>
>>> Just my 2c ;)
>>>
>>
>> Correct.
>
> But I don't see how any of those things apply here. If the host fails your vm's
> are going to fail in any case, and there's not much magic involved in exporting
> an NFS share even if you need to move it. Iscsi targets are slightly more
> complicated because it's not included in the base Centos install
Sorry Less, Iscsi target is included in CentOS 5 base repository (package
scsi-target-utils).
but you can
> find howto's to set it up. When your resources are limited it looks like a big
> waste to add an unnecessary virtual layer to storage. I've done it the other
> way around, though, with NFS exports from the host being mounted by the guest VM's.
>
This is th first step. Next step is to make physical HA infraestructure with
hypervisors.
--
CL Martinez
carlopmart {at} gmail {d0t} com