If one unmounts a disk, is that disk still available for write and can the following sync do anything?
Uhm, been a while since I had to think of this but pretty sure you used to need to do that the other way around. Sync before unmount, else things may still be being written to disk.
Surely an unmount forces a sync.
Yeah I’m thinking about fuse filesystems and hotplugged USB keys though. There was a time when the feedback about devices being ready to unplug was bad for users.
This answer suffered the fog of time. Never needed it with the unmount command.
Yes to the first question. I could be wrong, but I think you have to run umount on the directory sdx is mounted on, not sdx itself.
I was under the impression that the sync command makes device removal safer somehow. Even though the device was unmounted, there may be cached data that wasn’t written yet. Could be wrong about that, but it seems harmless to include.
Edit: looked it up, and umount calls sync, so there’s no need to include it. And if you do include it, sync before umount, like you said.
