Solution: Found natterr post that suggested deleting the peers, it worked for me: Can't ping devices
I have a ZeroTier installed on Ubuntu v20 (machine A), I can ping multiple machines on a remote network via the ZeroTier Connection, but one machine (machine B) I am unable to connect to. (Destination Host Unreachable).
I can however ping that machine B and machine A from other machines on the ZeroTier network. It’s just these two that can’t see each other…
No idea what to try, any suggestions / help / ideas appreciated.