There was a rather long moment of panic over the weekend during which 
time I nearly lost the Gopher server. Well, not actually lost (as in 
permanently) as I have backups, but the NUC holding the Gopher had a 
BIOS problem. As I'd recently updated the Web server and my spare 
backup SSD had arrived quickly I had a fine Clonezilla session and now 
have a swappable disk for the WWW. 

Flushed with success I decided to clone the Gopher server as well. 
It's a rather old NUC and I somehow managed to get ito run Linux before 
there was even official support from Intel. I've never updated the 
BIOS because I was too afraid TBH.. Anyway, I eventually managed to 
tweak the setup settings to allow a disk clone to take place, and 
confidently did a powerdown followed by a reboot. Or not. To cut a 
long story short it would not recognise either original or cloned SSDs 
as boot devices. 

Panic set in. I knew that my later NUCS would have no problem but I 
didn't want to buy more hardware as the NUC was still working well. I 
eventually ended up resetting all settings to factory defaults, and 
made sure it wasn't booting from the UEFI partition. After a couple of 
hours fiddling with settings, I eventually got the dratted thing to 
boot and I was back on the road again. 

Longer-term I will replace the original NUC, but for now, I have a 
cloned SSD backup which makes me feel a lot safer!