topic Re: NFS GID limit in Operating System - Linux

NFS GID limit

SIG. ENRICO CRIPPA — Tue, 24 Nov 2009 13:48:03 GMT

Hi all,
I have a problem with GID and NFS
On RHEL5 server (servA) i export a file system where a directory is root.group owned and perm 2770.

/etc/export
/dirroot/fs xxx.xxx.0.0/16(rw)

ls -l /dirroot
drwxrwxrwx 4 root root 4096 Nov 24 14:06 fs

ls -ln /dirroot/fs
drwxrws--- 2 0 10021 4096 Nov 24 14:08 prv1
drwxrws--- 2 0 10022 4096 Nov 24 14:06 prv2

On an RHEL5 client (servB) i mount the fs.

Now on servB i can read and write into prv1 (gid=10021), but i have a 'permission denied' when i read prv2.

Naturally mi user (user1) exist via LDAP on every server, groups '10021' and '10022' are defined on every node (via LDAP), and the user is member of both groups

Can anyone help me?

Thanks,
Daniele

Re: NFS GID limit

Ivan Ferreira — Tue, 24 Nov 2009 16:11:54 GMT

NFS has a limitation on the numbers of groups that a user belongs, I thinks is 16. How many groups your users belongs to?

See:

http://nfsworld.blogspot.com/2005/03/whats-deal-on-16-group-id-limitation.html

Also, the permissions for the fs directory allows write to others, your security is in risk with this setting.

Re: NFS GID limit

SIG. ENRICO CRIPPA — Tue, 24 Nov 2009 16:25:28 GMT

Hi Ivan,
in effect the 10021 and 10022 gid are on the limit of the 16th and 17th element in the list of groups for mi user (id userid).

Thanks,Daniele