On Thu, 2010-12-09 at 07:51 -0500, Steve Dickson wrote: > > On 12/08/2010 09:56 AM, Ondrej Valousek wrote: > > On 08.12.2010 14:45, Ian Kent wrote: > >> On Wed, 2010-12-08 at 13:51 +0100, Ondrej Valousek wrote: > >>> On 08.12.2010 13:36, Ian Kent wrote: > >>>> The default should be determined by mount.nfs(8) since that's what > >>>> autofs uses to perform mounts. > >>> I see, but it works only if the nfs4 root export is the same as /. It > >>> does not work otherwise. Example: > >>> Server 'dorado' exporting directory /exports which is also fsid=0 for > >>> nfs4. > >>> There is (also shared) subdirectory 'ext1' in this one. When I do: > >>> > >>> cd /net/dorado/exports/ext1 > >>> > >>> ... the export is mounted using NFSv3. Theoretically if I did: > >>> > >>> cd /net/dorado/ext1 > >>> > >>> ... I should have the same mounted via NFSv4, right? Unfortunately it > >>> does not work. But it should because: > >>> > >>> mount dorado:/ext1 /mnt > >>> > >>> works (giving nfs4 mount).... > >> The only information the hosts map has to go on is the export list > >> received from the server. > >> > >> There is no way for autofs to know that /exports is the global root from > >> the mountd exports information. It only knows that /exports is an export > >> and neither does it know what NFS version the server may offer for this > >> mount. That information just isn't available. > >> > >> As I said, I thought in recent Fedora releases (not sure now when this > >> should have happened), that > >> > >> mount <server>:/exports /<some mount point> > >> > >> and > >> > >> mount <server>:/ /<some mount point> > >> > >> should both work and mount as NFSv4. Correct me if I'm wrong but your > >> point is that it is mounting as NFSv3 so perhaps we should log a bug and > >> see what the experts have to say on this. > >> > >> Ian > >> > >> > > Hi Ian, > > > > I understand that autofs can not know that /exports is a global root. I > > just thought that mine: > > > > cd /net/dorado/ext1 > > > > ... (i.e. omitting the "exports" word) should work as this way should > > autofs pass something like this : "mount.nfs dorado:/ext1 /net/dorado/ext1" > > which would succeed then, resulting in a nfs4 mount. What happens now is > > (obviously) that autofs can not find 'ext1' in the exports information from > > 'dorado' and so it fails even without trying.... > It depends on your server... If your server does not support v4, the > mount will roll back to v3. An rpcinfo -p <server> will show if > the server support v4.
Knowing that the server supports NFSv4 doesn't tell me which export is a global root though (does it?). I guess I could code the rpcinfo calls and rewrite the mount code to retry if v4 is supported. Not sure I like that idea though. My problem is knowing for sure what the global root is and then I also don't know what mount.nfs(8) will do with it. If I did have some way of knowing what the global root was then trying to accommodate it will cause mounts that fall back to v3 to fail. I thought that the recent NFS server changes were meant to allow both the mount paths above to function, like I think they do on other OSes (I'll check on that if you really want me to)? Ian _______________________________________________ autofs mailing list autofs@linux.kernel.org http://linux.kernel.org/mailman/listinfo/autofs
