Need Some explanation about n iSCSI-based storage pool

Need Some explanation about n iSCSI-based storage pool

[Expert Alert]

Hi
I have a confusion about how LUN and iSCSI-based storage pool.
Example, if i have 80GB size of  LUN, and i added that one
 into KVM iSCSI base storage pool.

now if i want to create a VM of 8GB in that storage pool,
 i will have waste the whole 80GB of Lun ??

Can i not create multiple VM under 1 iSCSI LUN ??

example, under vmware, I can attach a  LUN as a storage
 and i will be be create multiple vm under 
that storage..
looks like i cant do that under KVM .
is that right ??

Which means, If i  want to create 3, 8GB vm,
 i will have to create 3 Lun  of 8GB size and  create 3 
Storage Volume then create vms on their ?

Please let me know

Thanks

Re: Need Some explanation about n iSCSI-based storage pool

[Paolo Bonzini]

Il 03/11/2013 10:18, Expert Alert ha scritto:
> Hi
> I have a confusion about how LUN and iSCSI-based storage pool.
> Example, if i have 80GB size of  LUN, and i added that one
>  into KVM iSCSI base storage pool.
> 
> now if i want to create a VM of 8GB in that storage pool,
>  i will have waste the whole 80GB of Lun ??
> 
> Can i not create multiple VM under 1 iSCSI LUN ??
> 
> example, under vmware, I can attach a  LUN as a storage
>  and i will be be create multiple vm under 
> that storage..
> looks like i cant do that under KVM .
> is that right ??
> 
> Which means, If i  want to create 3, 8GB vm,
>  i will have to create 3 Lun  of 8GB size and  create 3 
> Storage Volume then create vms on their ?

Just like you'd create VMFS for that LUN under VMware, you can configure
LVM or create a filesystem like ext4 or XFS inside the LUN.  Then you
can split the LUN as you wish.

Paolo

Re: Need Some explanation about n iSCSI-based storage pool

[Expert Alert]

Paolo Bonzini <pbonzini <at> redhat.com> writes:

> 
> Il 03/11/2013 10:18, Expert Alert ha scritto:
> > Hi
> > I have a confusion about how LUN and iSCSI-based storage pool.
> > Example, if i have 80GB size of  LUN, and i added that one
> >  into KVM iSCSI base storage pool.
> > 
> > now if i want to create a VM of 8GB in that storage pool,
> >  i will have waste the whole 80GB of Lun ??
> > 
> > Can i not create multiple VM under 1 iSCSI LUN ??
> > 
> > example, under vmware, I can attach a  LUN as a storage
> >  and i will be be create multiple vm under 
> > that storage..
> > looks like i cant do that under KVM .
> > is that right ??
> > 
> > Which means, If i  want to create 3, 8GB vm,
> >  i will have to create 3 Lun  of 8GB size and  create 3 
> > Storage Volume then create vms on their ?
> 
> Just like you'd create VMFS for that LUN under VMware, you can configure
> LVM or create a filesystem like ext4 or XFS inside the LUN.  Then you
> can split the LUN as you wish.
> 
> Paolo
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo <at> vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> 


Hi
First of all ,thank you very much for quick reply

only one confusion.

"

you can configure
LVM or create a filesystem like ext4 or XFS inside the LUN.

"

What about if i try to migrate the VM into another KVM server ??

if i attached that LUN into another KVM server will i 
be able to migrate the VM ??
 ( I have done 
Migrate by nfs share)

in that case how Migrate work ??


Kind Regards

Re: Need Some explanation about n iSCSI-based storage pool

[Paolo Bonzini]

Il 03/11/2013 10:43, Expert Alert ha scritto:
> you can configure
> LVM or create a filesystem like ext4 or XFS inside the LUN.
> 
> What about if i try to migrate the VM into another KVM server ??
> 
> if i attached that LUN into another KVM server will i 
> be able to migrate the VM ?? ( I have done Migrate by nfs share)

For ext4 of XFS, you need to use an NFS share indeed.

For LVM, you can access it on multiple systems using an additional
daemon (clvmd) to propagate state changes between cluster nodes.  It may
not be necessary to use clvmd if the configuration of the logical
volumes is static.

Paolo

> in that case how Migrate work ??
> 
> 
> Kind Regards
> 
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>