First of all many many thanks for this ! Perhaps not the right place for this question but how this would work during upgrade, have you tested that ? would the data being copied on all ESPs ? I have to comment the /dev/gpt/efiboot0 line on fstab, without that when the first drive fails I am dropped to single mode , so I am wondering if commenting is the right thing to do (as this would not being mounted would it be impacted by potential upgrades). Many thanks for the clarification