[linux-lvm] Wisdom of multiple disks in one VG

[Ross Boylan <ross biostat ucsf edu>]

If I have a Volume Group with partitions from 2 different physical disks
on it, and I confine my logical volumes to particular physical disks,
will I be able to recover the logical volumes on disk 1 if disk 2 fails?

I have several disks, but they are all different sizes and so don't seem
like good candidates for a scheme with redundancy (e.g., RAID 5).
Because of my concern that combining disks into the same volume group
would mean a failure of 1 would effectively wipe them all out, I have so
far used separate VG's for each disk.  However, this is awkward.

So, my general question is what the best approach would be in this
situation, multiple disks of much different sizes.  The existing disks
all have separate VG's on them.  The biggest disk is empty so far.

Thanks for any advice.
Ross Boylan