[SOLVED] NFS subdirectory - regular user can read

qajaq · 12-29-2016, 08:35 AM

I've set up a file server using nfs4 and included the following lines in my file-server's /etc/exports file:

Code:

/share 192.168.0.30(rw) 192.168.0.40(rw)
/share/datalib 192.168.0.30(rw) 192.168.0.40(rw)

Now, as a regular user on the 192.168.0.40 machine, I can read and write to any file anywhere in the shared directory tree, even in levels beyond the two levels listed in the server's exports file.

However, as root user, I have permission only to read or write to files immediately in those two specified directories. When I try to list files one level beyond those two, I get a "Permission denied" error message.

The relevant UIDs and GIDs are identical on both machines. And even aside from that, I thought the root user should have universal permissions, no?

What could be going on to prevent the root user having access to files that a regular user can fully manipulate?

cliffordw · 12-29-2016, 09:12 AM

Hi there,

Have a look at "man exports", and in particular the "User ID Mapping" section. It says:

Quote:

Very often, it is not desirable that the root user on a client machine is also treated as root when accessing files on the NFS
server. To this end, uid 0 is normally mapped to a different id: the so-called anonymous or nobody uid. This mode of operation
(called `root squashing') is the default, and can be turned off with no_root_squash.

I hope this helps

qajaq · 12-29-2016, 12:59 PM

Yes, that did help completely. Thank you very much!