Which version of Debian from which physical device?

[Richard Owlett <rowlett@cloud85.net>]

I have a laptop set aside for experimenting with configuration 
options.
I currently have 2 instances each of Squeeze(Gnome DE) and 
Jessie(Mate DE).
My current practice has been during install to give meaningful 
names to the machine.
I.E. when using terminal the prompt may be "richard@min-squeeze" 
or "richard@max-jessie", etc. That is usually sufficient.

However today, while chasing down an intermittent problem, I 
needed to know which point release was active and which physical 
device contained the OS. Usually I have gparted installed and can 
determine the active device by the "locked" symbol.

Is there a log file with the info?
TIA