[KLUG Members] NFS and time travel

[Adam Williams]

> > >>The results are no different if I use IP addresses now.
> > >Try IP's anyway, if you haven't.  
> > I have, whch is why I wrote what I did. I'm reporting, not speculating.
> And I'm making absolutely sure.   :-)
> I guess the next thing I'd try is trial & error with different options
> (on mount and in exports).
> And, since this is for your internal network, why are you specifying
> hostnames or IP's at all?  Why not export them to the world?  (try it!)

I've seen this work.  When trying to mount a Linux2.2 NFS volume on an
AIX box it only worked if it was shared to "*(rw,insecure)".  Forgot
about that one.  Ugly ugly and I never had a flippin' clue why.

> At least I hope this is only for your internal network only.  
> You should know that NFS stands for:  "No File Security".   ;-)

NFSv4 mandates support for GSSAPI (Kerberos V) for RPC calls. 
Hallelujah!  NFSv4 is in 2.6.x I think but I haven't checked.  All
network file operations encrypted and authorized,  now thats gonna be
nice.

Also NFSv4 does away with the gid/uidNumber matching agony.  Usernames
and groups are processed as strings and gid/uidNumber hashing can be
processed locally.  So much nicer.

> > >I've had weird problems that's solved before - to the point I _always_
> > >use IP addresses in /etc/exports now.  (and "permission denied" is
> > >almost always a /etc/exports problem)
> > It looks like some odd problem with DNS, maybe reverse lookups or
> > something [??].
> Could be.  It's been too long to remember.  I got in the habit of using
> IP's a LONG time ago.

Or at least only hostnames defined in /etc/hosts.

> > >Other things to watch out for: 
> > Nice to have this checklist, for general reference...
> The only other thing I can thing of (for general reference) is nested
> exports.  I've seen people make the mistake of exporting both:
> "/a/b/c/d/e"   -and-   "/a/b/c"   Which causes problems.  
> Only the second export is needed to mount either.

Yep.  Submounting will make NFS go bonkers.