vfs_gpfs — gpfs specific samba extensions like acls and prealloc
vfs objects = gpfs
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.
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.
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
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
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
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
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