vfs_gpfs

Name

vfs_gpfs — gpfs specific samba extensions like acls and prealloc

Synopsis

vfs objects = gpfs

DESCRIPTION

This VFS module is part of the + samba(7) suite.

The gpfs VFS module is the home + for all gpfs extensions that Samba requires for proper integration + with GPFS. It uses the GPL library interfaces provided by GPFS. +

Currently the gpfs vfs module provides extensions in following areas : +

NFSv4 ACL Interfaces with configurable options for GPFS
Kernel oplock support on GPFS
Lease support on GPFS

NOTE:This module follows the posix-acl behaviour + and hence allows permission stealing via chown. Samba might allow at a later + point in time, to restrict the chown via this module as such restrictions + are the responsibility of the underlying filesystem than of Samba. +

This module is stackable.

OPTIONS

nfs4:mode = [ simple | special ]

+ Enable/Disable substitution of special IDs on GPFS. This parameter + should not affect the windows users in anyway. It only ensures that Samba + sets the special IDs - OWNER@ and GROUP@ ( mappings to simple uids ) + that are relevant to GPFS. +

The following MODEs are understood by the module:

simple(default) - do not use special IDs in GPFS ACEs
special - use special IDs in GPFS ACEs.

nfs4:acedup = [dontcare|reject|ignore|merge]

+ This parameter configures how Samba handles duplicate ACEs encountered in GPFS ACLs. + GPFS allows/creates duplicate ACE for different bits for same ID. +

Following is the behaviour of Samba for different values :

dontcare (default) - copy the ACEs as they come
reject - stop operation and exit with error on ACL set op
ignore - don't include the second matching ACE
merge - bitwise OR the 2 ace.flag fields and 2 ace.mask fields of the 2 duplicate ACEs into 1 ACE

nfs4:chown = [yes|no]

This parameter allows enabling or disabling the chown supported + by the underlying filesystem. This parameter should be enabled with + care as it might leave your system insecure.

Some filesystems allow chown as a) giving b) stealing. It is the latter + that is considered a risk.

Following is the behaviour of Samba for different values :

yes - Enable chown if as supported by the under filesystem
no (default) - Disable chown

EXAMPLES

A GPFS mount can be exported via Samba as follows :

+        [samba_gpfs_share]
+	vfs objects = gpfs
+	path = /test/gpfs_mount
+	nfs4: mode = special
+	nfs4: acedup = merge
+

CAVEATS

The gpfs gpl libraries are required by gpfs VFS + module during both compilation and runtime. + Also this VFS module is tested to work on SLES 9/10 and RHEL 4.4 +

VERSION

This man page is correct for version 3.0.25 of the Samba suite. +

AUTHOR

The original Samba software and related utilities + were created by Andrew Tridgell. Samba is now developed + by the Samba Team as an Open Source project similar + to the way the Linux kernel is developed.

The GPFS VFS module was created with contributions from + Volker Lendecke and the developers at IBM. +

This manpage was created by the IBM FSCC team