On Mon, 2008-11-03 at 14:34 -0500, Daniel Gruner wrote:
> The group and passwd file are copied from the master (well, only some
> entries), but in any case they match.
> 
> I was fearing you'd tell me about the public keys... :-(
> 
> The answer to that is that I don't mount the home directories on the
> nodes by default, and I wasn't planning to do so, period.  

xcpufs skips over the user if it cannot find the user's public key in
the home directory mounted locally.

> In fact, in
> some sense having the password files and keys available on the nodes
> kind of defeats the security safeguards built into xcpu, especially if
> one uses the xcpufs -u option.  It would be far better to do as we
> discussed before:  let the scheduler assign the permissions.
> 
> In the meantime (until the bjs port is available), this may still be
> the only way to do it...

if you can pull the latest trunk, you can use the -u switch from x*set
to do the same:

xgroupset add n0000 -u (to add all groups)
xgroupset add n0000 -u (to add all users)

let us know if this works for you.
thanks!

> 
> Another option would be to somehow make available just the users'
> public keys, collected in some directory structure, and modify the
> init_unix_users() routine in xcpufs.c accordingly.  What do you think
> about this?
> 
> Daniel
> 
> 
> On 11/3/08, Abhishek Kulkarni <[EMAIL PROTECTED]> wrote:
> >
> >  can you make sure the group and passwd files on the node match with
> >  those on the master?
> >
> >  xcpufs also looks for the public key of the user in it's home directory
> >  specified in the /etc/passwd file. so make sure that the key is readable
> >  by xcpufs on the node.
> >
> >
> >  On Mon, 2008-11-03 at 12:42 -0500, Daniel Gruner wrote:
> >  > Immediately after booting:
> >  >
> >  > [EMAIL PROTECTED] xcpufs]# xgetent group n0000
> >  > xgetent: n0000: Error 5: unknown user
> >  > [EMAIL PROTECTED] xcpufs]# xgetent passwd n0000
> >  > xgetent: n0000: Error 5: unknown user
> >  >
> >  > which is consistent with what I mentioned, i.e. that the '-u' flag to
> >  > xcpufs didn't do anything.
> >  >
> >  > After doing xgroupset and xuserset manually:
> >  >
> >  > [EMAIL PROTECTED] xcpufs]# xgetent group n0000
> >  >
> >  > Group Database From Node: n0000
> >  > danny:500
> >  > root:0
> >  > xcpu-admin:65530
> >  > [EMAIL PROTECTED] xcpufs]# xgetent passwd n0000
> >  >
> >  > Password Database From Node: n0000
> >  > danny:500:500
> >  > root:0:0
> >  > xcpu-admin:65530:65530
> >  >
> >  > Daniel
> >  >
> >  > On 11/3/08, Abhishek Kulkarni <[EMAIL PROTECTED]> wrote:
> >  > >
> >  > >  On Mon, 2008-11-03 at 11:52 -0500, Daniel Gruner wrote:
> >  > >  > I have modified the perceus scripts so that before xcpufs is run 
> > there
> >  > >  > exist on the nodes the /etc/group and /etc/passwd files.  However,
> >  > >  > even if I run "xcpufs -u" the group/user membership is not set, as 
> > you
> >  > >  > suggest it should be.  I am using a statically linked version of
> >  > >  > xcpufs on the nodes (freshly compiled, not the one that comes with
> >  > >  > perceus).
> >  > >  >
> >  > >  > How might one go about debugging this?
> >  > >  >
> >  > >
> >  > >
> >  > > what is the output of:
> >  > >
> >  > >  xgetent group <nodename>
> >  > >  xgetent passwd <nodename>
> >  > >
> >  > >  from the perceus master?
> >  > >
> >  > >
> >  > >  > Thanks,
> >  > >  > Daniel
> >  > >  >
> >  > >  > On 11/2/08, Abhishek Kulkarni <[EMAIL PROTECTED]> wrote:
> >  > >  > >
> >  > >  > >  >
> >  > >  > >  > Sorry, but don't follow.  Are you talking about perceus 
> > modules? I
> >  > >  > >  > didn't think we wanted standard passwd/group files sent to the 
> > nodes,
> >  > >  > >  > which is what perceus normally does.
> >  > >  > >
> >  > >  > >
> >  > >  > > Yes, I was talking about Perceus modules. "groupfile", 
> > "passwdfile" are
> >  > >  > >  modules which just copy the group and passwd file (respectively) 
> > from the
> >  > >  > >  perceus master to the slaves.
> >  > >  > >
> >  >
> >  > >  > >
> >  > >  > >   I can't even find where xcpu
> >  > >  > >  > stores the information for xgroupset/xuserset! (I guess this 
> > shows
> >  > >  > >  > that it is not trivial to get into the xcpu code...).  Also, 
> > what do
> >  > >  > >  > you mean by the "-u" switch for xcpu?  Oh, I just looked at 
> > xcpufs.c
> >  > >  > >  > and I see it there - it is not in the man page for xcpufs, 
> > though...
> >  > >  > >  > I guess this would do the trick if we simply want all users 
> > and groups
> >  > >  > >  > to be authenticated on the nodes at all time.
> >  > >  > >
> >  > >  > >
> >  > >  > > the group and user information is stored by xcpufs in a userpool 
> > structure
> >  > >  > >  in-memory. the -u switch is to automatically add all the users 
> > and groups
> >  > >  > >  to the pool. it would do the trick only if the users and/or 
> > groups you
> >  > >  > >  want to be authenticated against are present on the slave nodes.
> >  > >  > >
> >  > >  > >
> >  > >  > >  I would much prefer to
> >  > >  > >  > have the batch queuing systems do this on a job-by-job basis, 
> > sort of
> >  > >  > >  > like the node ownership setting that bjs does on bproc 
> > clusters, since
> >  > >  > >  > this would prevent people from running interactively on the 
> > nodes that
> >  > >  > >  > are owned by someone else.
> >  > >  > >
> >  > >  > >
> >  > >  > > yes, that's the idea.
> >  > >  > >
> >  > >  > >
> >  > >  > >  >
> >  > >  > >  > Daniel
> >  > >  > >  >
> >  > >  > >  > On Fri, Oct 31, 2008 at 7:32 PM, Abhishek Kulkarni <[EMAIL 
> > PROTECTED]>
> >  > >  > >  > wrote:
> >  > >  > >  >>
> >  > >  > >  >> i believe the xcpu module is activated in the "init" 
> > provisionary stage
> >  > >  > >  >> and the groupfile/passwdfile modules get activated in the 
> > "ready" stage.
> >  > >  > >  >> so the way to do this would be to make the groupfile and 
> > passwd file
> >  > >  > >  >> modules to run before the xcpu module, and start xcpu with 
> > the "-u"
> >  > >  > >  >> switch
> >  > >  > >  >>
> >  > >  > >  >> or better yet: with the new -u switch in xuserset and 
> > xgroupset you
> >  > >  > >  >> could add all the users from the master node.
> >  > >  > >  >>
> >  > >  > >  >> Thanks,
> >  > >  > >  >>  -- Abhishek
> >  > >  > >  >>
> >  > >  > >  >> On Fri, 2008-10-31 at 14:54 -0400, Daniel Gruner wrote:
> >  > >  > >  >>> Hi
> >  > >  > >  >>>
> >  > >  > >  >>> I was wondering if anybody has scripts for a perceus-xcpu 
> > installation
> >  > >  > >  >>> that will automatically add groups and users to freshly 
> > booted nodes.
> >  > >  > >  >>> It appears to me that all the perceus scripts in
> >  > >  > >  >>> /etc/perceus/nodescripts run on the node itself, and not on 
> > the master
> >  > >  > >  >>> node, which is where one needs to execute the xgroupset and 
> > xuserset
> >  > >  > >  >>> commands.  Any help would be appreciated.
> >  > >  > >  >>>
> >  > >  > >  >>> Thanks,
> >  > >  > >  >>> Daniel
> >  > >  > >  >>>
> >  > >  > >  >>> p.s. Is anybody planning an xcpu get-together for SC08?  I 
> > think it
> >  > >  > >  >>> would be great...
> >  > >  > >  >>
> >  > >  > >  >>
> >  > >  > >  >
> >  > >  > >
> >  > >  > >
> >  > >
> >  > >
> >
> >

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