As i understood LVM san be used on unused disk and require reboot of system when rolling back. In my case i have existing disk /dev/hda1 with data that i can't modify or delete, but i have 20GB of 30GB free on this disk. So may be EVMS have such solution to make a snapshot on existing disk. I just a little confused with EVMS terminology. There are segments, regions, containers, object. What i exactly should to create for snapshot ?