[linux-lvm] lvm on a share environnement (SAN inside)

[hubert chomette <chomette ensil unilim fr>]

Hi,
I recently install a SAN at my work. One lun is used for XEN and can  
be used by two xen server.
For more flexibility I use lvm on this lun. I was very happy of the  
result, unless I discover (during a conversation with a friend) that  
lvm metadata can be compromised if the two server simulty modify  
metadata.
- So what can I do?
- Is it possible to allow LVM metadata modification by only one server?
- should I use clvm instead?
- Is it possible to migrate lvm to clvm without any data lost?

thank's for your help

regards,

ps: sorry for my poor english