Why anyone can read and write to a nobody NFS mounted volume?

[Rick Macklem]

Well, I suppose it is up to the server implementor. (In your case Seagate...)
Normally NFS servers map root->nobody by default, under the assumption that
"nobody" is not a real user and is checked via world permissions.
--> I'd say a typical server would allow anyone (including "nobody" access)
    if the file's mode includes world "rw".

But none of this is defined in any of the NFS RFCs as far as I recall (the
RFCs basically define what goes on the wire), so I think it is up to the
server implementor.
--> If the file doesn't have world permissions, then I would consider this
    atypical and you might want to check with the server implementor in case
    this is configurable?

Now, if you are using NFSv4 and uid<->user mapping isn't set up correctly,
any uid/gid that can't be mapped to another name will go on the wire to the
server as "nobody" (and "nogroup" if I recall it correctly). So, you might
want to "nfsstat -m" on the client to see if you are using NFSv3 or NFSv4
and try NFSv3 if it isn't already what you are using.

rick

----- Original Message -----
> Hello all!
> 
> i have a strange situation: everyone and not just root can read and write
> to a NFS mount point whose owner is nobody:nobody.
> 
> Is this an expected behaviour?
> 
> FreeBSD 10.2 RELEASE as NFS client.
> Seagate NAS400 as NFS server.
> 
> Thank you all,
> Raimundo Santos
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