On Wed, Dec 15, 2010 at 06:58:09PM -0500, Trond Myklebust wrote: > On Wed, 2010-12-15 at 17:55 -0500, J. Bruce Fields wrote: > > On Wed, Dec 15, 2010 at 05:29:28PM -0500, J. Bruce Fields wrote: > > > On Wed, Dec 15, 2010 at 05:15:46PM -0500, Trond Myklebust wrote: > > > > I'm quite happy to accept that my user may map to completely different > > > > identities on the server as I switch authentication schemes. Fixing that > > > > is indeed the administrator's problem. > > > > > > > > I'm thinking of the simple case of creating a file, and then expecting > > > > to see that file appear labelled with the correct user id when I do 'ls > > > > -l'. That should work irrespectively of the authentication scheme that I > > > > choose. > > > > > > > > In other words, if I authenticate as 'trond' on my client or to the > > > > kerberos server, then do > > > > > > > > touch foo > > > > ls -l foo > > > > > > > > I should see a file that is owned by 'trond'. > > > > > > Thanks, understood; but then, this isn't about behavior that occurs when > > > a user *changes* authentication flavors. > > > > > > It's about what happens when someone sets nfs4_disable_idmapping but > > > shouldn't have. > > > > In other words, to make sure I understand: > > > > - Is this switching-on-auth flavor *just* there to protect > > confused administrators against themselves? > > - Or is there some reasons someone who knew what they were doing > > would actually *need* that behavior? > > It is there to ensure that you can use different type of authentication > when speaking to different servers, and still have it work without the > administrator having to add special mount options. Oh, OK--now I understand, thanks! Then it really is just a restricted sort of per-mountpoint idmapping. As such I'm not sure I understand the relative merits of that versus (possibly per-server) idmapd configuration. But at least it seems tolerable. The biggest remaining problem either way is that the user experience on an NFSv3->NFSv4 upgrade is still: - oh, look, file owners look all wrong. - go find documentation of the needed configuration (domain setting in /etc/idmapd.conf, or nfs4_disable_idmapping option) --b. > As I've said before, the uid-on-the-wire behaviour only makes sense with > AUTH_SYS. It adds no value when authenticating using principals, and > will in many (most?) cases end up doing the wrong thing. > > Trond > > -- > Trond Myklebust > Linux NFS client maintainer > > NetApp > Trond.Myklebust@xxxxxxxxxx > www.netapp.com > -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
