[CentOS-virt] Best practices for LVM and virtualization

[Manuel Wolfshant]

Mathieu Baudier wrote:
>>> 3. On both host and guest
>>>       
>> This is what I always use and recommend. It doesn't have any side effects with modern software versions, except with layered
>>     
>
> Thanks!
>
> I have tried this, but I don't see how to grow the guest file system
> without restarting the guest:
> - if I grow the underlying logical volume on the host, the guest still
> see the hard drive with the old size (checking with fdisk)
> - if I would add additional logical volumes (host) / drives (guest) in
> order to add them to the guest volume group, I will have to restart
> the guest
>
> I am using virtio disks.
>
> Is there a command so that the guest notices that its harddrive has grown?
> Is there a way to add new drives without restarting the guest?
yes, you can add / remove disks to a VM without restarting the guest. 
look at the xm block-attach  / block-detach commands