[CentOS] group write permissions not being respected

Hi

We have just migrated our data to a new file server (more space, old 
server was showing its age). We have a volume for collaborative use, 
based on group membership.  In our new server, the group write 
permissions are not being respected (e.g.  the owner of a directory can 
still write to that directory but any other member of the associated 
group cannot, even though the directory clearly has group write 
permissions set).  This is occurring regardless of how many groups the 
user is a member of (i.e. users that are members of fewer then 16 groups 
are still affected).

the relevant fstab line from the server looks like
localhost:/data-volume /gdata    glusterfs       defaults 0 0

and for a client:
mseas-data2:/gdata       /gdata      nfs     defaults        0 0

Any help would be greatly appreciated.

Thanks

-- 

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Pat Haley                          Email:  phaley at mit.edu
Center for Ocean Engineering       Phone:  (617) 253-6824
Dept. of Mechanical Engineering    Fax:    (617) 253-8125
MIT, Room 5-213                    http://web.mit.edu/phaley/www/
77 Massachusetts Avenue
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