file permissions

Alan McKinnon alan at
Mon Sep 11 12:28:03 UTC 2006

On Monday 11 September 2006 14:00, Zoltan Szecsei wrote:
> The scenario is (ubuntu dapper):
> The directory of files is on host gl0 mounted with nfs3
> squashing to a specific user and group.
> User from other hosts that mount this directory copy files to
> their own host, edit them and "put" them back.
> The files on gl0 now have permissions 600 (instead of 775)
> and the squashed uid/gid.
> For users that are actually on host gl0, when they put the
> files back into the main directory, the permissions are still
> re-set to 600 but the uid/gid is that of their own (this is
> not a train-smash if I could get the darn permissions to
> remain 775).

Hey Zoltan,

I think we all had this conversation on clug as well a while 
back :-)

As I see it, the problem is that nfs does not enforce 
permissions on files written to exported volumes. From the 
user's point of view, whatever his umask is is what the 
permissions will be and beyond that the kernel/system doesn't 
interfere. i.e nfs trusts the client that it knows what it is 

This sounds like a job for samba, where you can enforce 
permissions of written files


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