On Mon, Jan 31, 2022 at 06:15:41PM +0100, Richard Weinberger wrote: > ----- Ursprüngliche Mail ----- > > Von: "bfields" <bfields@xxxxxxxxxxxx> > >> Using /proc/fs/nfsfs/volumes it is possible to find the NFS fsid > >> from the backend and use it as seed for mountd's UUID mechanism. > > > > Sorry, I haven't checked--what is that number, really? It's probably > > not the fsid returned from the server, as that wouldn't be guaranteed > > unique across multiple servers. But that means it's probably generated > > in a way that doesn't guarantee it's stable across reboots. And we need > > filehandles to work across reboots. > > Unless I badly misunderstood the code it comes from fs/nfs/client.c's > nfs_create_server() where the NFS client fetches NFS_ATTR_FATTR via getattr(). > So it should be unique: > https://datatracker.ietf.org/doc/html/rfc7530#section-5.8.1.9 Unique within one server, but not across different servers. Depending on how your servers assign fsids, collisions might be quite likely. Results of a collision would be pretty bad. --b.
