Lets say I have a machine which exports an nfs directory /mnt/sdb1.

Two other machines mount it. So now three machines are able to access machine 1s /mnt/sdb1. Is there a way to check if it is the same drive on all 3 machines? Is there some sort of ID that persists across the network?

I have tried the combination of inode and device ID, but the device ID is different across machines.