On Fri, Jan 10, 2020 at 10:22:44AM +1100, Dave Chinner wrote:

Yeah, and if you add the equivalent of 'lsblk -f' then you also get
the fs UUID to identify the filesystem on the block device at a
given time....

The UUID usually already gets recorded and displayed:

# lsblkj -f --until "2020-01-09 22:00:00"
NAME                             FSTYPE      FSVER LABEL UUID                                   FSAVAIL FSUSE% MOUNTPOINT
sda                                                                                                            
├─sda1                           xfs                     78524ad6-6445-4bb6-840b-194871231274   
...

(It's also capturing something simple for mountpoint when it can, but so far that's
only visible with journalctl.)
 
Alasdair