[CentOS] How to backup LV for XenU on Centos

Hi,

 Here is a newbie to Xen and LVM on Centos. I've created a Logical Volumn(LV) in the domain 0. and then install a XenU on the LV. IN more details: The LV is exported to XenU as xvda, and default Centos disk Layout is accepted -- /dev/xvda1 for /boot, /dev/xvda2 as Physical Volumn).

Now my problem is: How to backup the Logical Volumn(LV) from Domain 0? I currently use dd to save it, is this the proper way? or can I create snapshot LV of the LV and 'dd' the snapshot LV? Because on the LV it is not a ext3/xfs file system, then I could not mount the LV, right?

Any one please shed a light onto this? What's the normal way to backup LVs which are exported to install XenU System?

Thanks a lot.