[CentOS-virt] how to add file-based disk space to a guest

Wed Jul 20 15:22:12 UTC 2011
thomas veymont <thomas.veymont at gmail.com>

hi there,

I'm following these documentations to add a file-based disk volume to
a KVM guest under Centos 6.0 :
http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization/chap-Virtualization-Storage_Volumes.html

as instructed, I created a "pool" then a "volume", file-based, e.g :

mkdir /mnt/raid/kvm_pool1
virsh # pool-define-as pool1 dir - - - - "/mnt/raid/kvm_pool1"
virsh # pool-autostart pool1
virsh # vol-create-as pool1 volume1 20G --allocation 15G --format qcow2

now I want to associate "volume1" to my guest OS. Following this doc:

http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization/sect-Virtualization-Virtualized_block_devices-Adding_storage_devices_to_guests.html

- why does this ask me to create a file with "dd" ? it's already been
created before with the virsh pool commands, isn't it? Seems to
me I'm bypassing the libvirt/virsh layer if I do that.

- after that, the doc tells me to do some stuff with guest XML files.
Is'nt there some specific commands provided by
virsh to associate a managed Pool to a managed Guest ?

- in this case, should I use the virsh "attach-disk" command ?

thanks.
--
Tom