[linux-lvm] Snapshots and disk re-use

[Jonathan Tripathy <jonnyt abpni co uk>]

Hi Everyone,

We host many Xen VMs for customers. We use LVM as the fisk storage for 
these VMs. When a customer cancels, we generally dd their LV with 
/dev/zero, before removing the LV.

If however we want to create a snapshot of a customer's LV, is there the 
chance that the data may appear on a new future LV if we were to create 
one (for a new customer)? Is is my understanding that most filesystems 
don't actually remove data from a disk when deleting a file, but just 
set an "ignore" tag of some sort...

Thanks