Re: [Fedora-xen] add 2 lvm to guest with virt-manager

[Mark Nielsen]

Augusto Castelan Carlson wrote:
>  Hi!
>
>    
> > Are you trying to use 2 logical volumes to separate / and /boot inside
> > the VM, or present 2 logical volumes (which would show up as 2 separate
> > disks entirely, xvda and xvdb for instance) to the guest from domain-0?
> >     
>
>  I'm trying to present 2 logical volumes to the VM.
>
>    
> > If you are trying to present 2 logvols to the VM itself, those will show
> > up as 2 separate disks inside the VM, as I mentioned (xvda, xvdb, or in
> > HVM sda, sdb, .. you get the idea) and I would wonder why you would want
> > to do that.
> >     
>
>  How can I present 2 logvols to the VM?
>
>  I proposed to my "boss" to present one logvols to the VM and then do
>  the partitioning inside the VM (xvda1 = /home, xvda2 = /groups,...),
>  but he wants to present 2 logvols, one to be used for /home and the
>  other for /groups...
>
>     
OK, well I'm not sure what benefit this would provide you honestly. I am 
assuming that both logvols you present to the VM are coming from the 
same storage (be it SAN or local disk). You are lucky (if you insist on 
using virt-manager), however, in that it's /groups you want to partition 
off. You could simply install the system as normal with /, /boot, /home, 
et al, residing on xvda. Then you shut the VM down, edit the config file 
for the VM to add the second logical volume as xvdb, start the VM back 
up and fdisk/partition/format and create your logical volumes as you 
would normally. Think of it as installing a new box, then shutting it 
down to physically add a new hard disk. It makes things a little easier 
it you think of VMs as being just like any other server, the same thing 
you'd do to a physical box you have to pretty much do with a VM (there 
are exceptions, block attach, etc) but the hardware is just "virtual" 
vs. physical.

OR -- simpy use virt-install. It's a cmd line based too, but I find 
faster and simpler to use. The -f flag is used to present a disk, you 
just add -f as many times for as many logical volumes you want to 
present. I would expect that it orders them just as you do on the 
command line.
>  Do you believe that is better to present only one logvols? If so,
>  please tell me, maybe a can convince him about use only one.
>
>     
I add 2 logical volumes all the time to just about every VM I have, but 
I typically do it because the LV in question is shared among VMs with 
GFS partitions inside the VM in a cluster of virtual systems :) again, 
just add -f as many times as you want using virt-install.
>  Thanks!
>
>  Regards,
>  Augusto
>