LVM data corruption

[Xen]

Gave you the wrong reference.

"https://www.redhat.com/archives/linux-lvm/2017-January/msg00013.html"

Is the right one.

I wrote

"It immediately replaced the good PV with the bad PV (that I was trying 
to change) so I cannot actually get to the "bad" PV (which is duplicate) 
to change it without booting an external system in which I can effect 
one disk in isolation."

"Even inserting a USB stick could crash a system like this."

to which Teigland responded:

"The handling of duplicate PVs has been entirely redone in recent 
versions.
The problems you are having are well known and should now be fixed."